Find this page in error and looking for the fishing season in Yellowstone or in Montana? Click the appropriate jurisdiction in the previous sentence. You might want to stick around and read this site before you go, because it'll give you a lot of useful info.
The season plays a huge role in determining where and how you should be fishing in the Yellowstone Area. In-depth information on how to approach particular bodies of water included on the appropriate page under the Guide to Area Waters menu, while detailed hatch and fly information is provided under the Flies & Hatches menu. This page is intended to give a general overview about what's fishable when.
Season has a profound effect on the fisheries in the Yellowstone area. Coming to fish the Firehole in July when it is warmer than most outdoor swimming pools or trying to fly cast on the Yellowstone in the midst of runoff in May, while trees float down it and you can't see your boots through the mud would put a serious damper on your trip. Use the information on this page to start planning when to come, or to get an overview of what to expect when you'll be here, if you've already set your travel dates, then delve into the rest of this site for more-detailed Yellowstone fly fishing tips and information.
Here's one more note before you start reading: "season" is a very imprecise term around here. It can snow in July, for example. The biggest reason for the massive swings in weather is the variety of elevations we have in Montana and Yellowstone Park. I fish and guide at waters over 7500 feet and under 3500 feet, for example. This means that it might feel like summer on the low-elevation Missouri River while you still have to hike through rotting snow to fish many places in Yellowstone Park. As such, the dates for each season as I discuss them below have a little leeway. Late May often feels like early spring or evern winter at high elevations, while at low elevations you'll often be able to be out and about in short sleeves, for example.
Early spring, from Late February or Early March through May (yep, late May is still “early spring,” even though on low-elevation rivers like the Missouri it might feel more like summer at times), has a great deal to offer visiting anglers. Crowds are minimal, the fishing can be outstanding, and with the possible exception of late autumn, it offers visitors the best shot at the largest trout of the year.
That said, it’s not for everybody. Yellowstone National Park remains closed to fishing until Memorial Day weekend, limiting opportunities to water outside the park. The weather can be awful, with heavy snow possible at all elevations throughout this period. The fishing, while productive, typically requires techniques that can be hard for beginner and novice anglers. Most of the fishing also requires nymphs and streamers, so dry fly fanatics will only have marginal opportunities. Last but not least, late in this period, the spring runoff begins on all freestone rivers (those without dams or a very sizable spring water component) and turns them into raging brown, unfishable torrents.
With the exception of the Missouri River, which is arguably at its best during this period, particularly for numbers of fish if not for dry fly fishing, all of the caveats in the last paragraph make early spring a poor choice for your first visit to the Yellowstone and southern Montana region. It’s a great choice for later visits, once you’ve “knocked the edge off” and are okay with somewhat more challenging and less consistent fishing, for the shot at one or two spectacular days.
“Variable” is the only word that can describe weather and water conditions during this period. It can be 75 degrees on the Missouri River in March, then snow sideways in late May in the same place. In fact, this wide variability is one reason I defined early spring as I did. By June 1, snow is unusual at low elevations (though it still occasionally falls). Before that, you had better come prepared to fish in the snow. Of course, if you bring winter clothing it will never get below 60 degrees, but that’s better than needing the winter gear and only having a tee-shirt…
To be more specific, throughout this period you must come prepared for any kind of weather, from warm and sunny with calm winds to torrential downpours or heavy snow, possibly accompanied by gale-force winds. If you come in March or the first half of April, it’s a good idea to bring ski gear in addition to your fishing tackle, because many of the ski area in the region are actually at their best during this time, and all remain open until at least early April.
The water on the spring creeks always stays clear during this period (and all the time), but on freestone rivers (at this time of year meaning the Yellowstone and Gallatin Rivers only), the water clarity and level can change drastically, even over a period of a few hours. Generally speaking, abnormally warm weather will raise water levels the next day, especially if this weather is accompanied by warm rain upon high-elevation snow, while cold snaps can quickly drop levels and improve clarity, though water temperatures often nosedive and put the fish into a stupor. On tailwaters, the Missouri and Madison, flows generally increase more or less steadily during this period, as the reservoirs upstream are drawn down in preparation to hold the heavy snowmelt to come, but it is exceptionally rare for rivers of this type to get too muddy to fish, at least down to the first substantial tributaries downstream of the dams that control their flow. The Missouri, in particular, almost never gets too muddy to fish downstream of Canyon Ferry Dam, which encompasses the two great tailwaters (below Hauser and especially Holter Dams) which make this river great. Lakes generally remain frozen until sometime in late March (low-elevation lakes) to early May (high-elevation lakes). They are usually very good the moment they lose their ice.
The heavy spring runoff begins by the middle of May on all freestone rivers and streams. What is runoff? The spring snowmelt in the mountains (the valley snow melts in March and April and only dirties the water slightly, if at all). This high-elevation snow all melts in a rush and runs downhill and turns these rivers into chocolate torrents. This is not a case of “the fishing is going to be a little tough.” It’s a case of “there are full-grown trees and dead big game animals floating down the river at 10mph.” What were clear, pretty mountain rivers and streams a few days before are now raging, often flowing at many times their previous volume. The fishing is nonexistent, and it can be dangerous to even be on the water in a whitewater raft, due to all the debris in the water. The Yellowstone River typically runs around 2,000 cubic feet per second flow on May 1, but at peak runoff near the end of May, it can be floating at 30,000, for example. The fishing is often quite good right before the heavy runoff begins, so it makes sense to try to hit the Yellowstone or Gallatin River just before the runoff starts, but you must have a backup plan in case you mistime things, because once the heavy runoff hits, the fishing is DONE on freestones until early summer. This applies to all freestone streams, large and small. All are out of play from sometime in May until at least the middle of June, and in some cases into early-mid July.
Top fisheries in early spring within the Yellowstone Country Fly Fishing and Parks’ Fly Shop operations areas change as this period progresses. Early on, the Missouri, Paradise Valley Spring Creeks, and Yellowstone Rivers are your best choices. As early spring progresses, basically during the month of April, the Madison River gets better and better and private ranch lakes experience ice-out and get red-hot right away.
By late April or early May, the Yellowstone River begins seeing some bouts of early melt during warm spells and often goes out of play for a few days. These bouts get more severe and more common as spring progresses, so having a backup plan gets more and more important. The private lakes and spring creeks remain great nearby options. Sometime in the first ten days of May (roughly), the Mother’s Day Caddis hatch begins on this river. If the river has not yet entered the worst of spring runoff, this hatch can provide the best dry fly fishing anywhere in the region, with 100+ fish possible. This only happens about one year in three. The rest of the time, the river enters the heavy spring melt and becomes unfishable before the hatch really gets going.
Once the Yellowstone River blows out, the private lakes and the lower Madison River are the best options within about two hours of Parks’ Fly Shop. The spring creeks usually get less consistent at this time. This is usually the best time on the private lakes, with the possible exception of late fall.
Further afield, the Missouri gets steadily more interesting, if not necessarily better. By “interesting,” I mean that the trout fatten up after a long winter and rigorous spawn, thereby getting stronger and prettier, start feeding on the surface more, and eat a wider variety of food items after fixating on the eggs of their cousins earlier in the spring. Since the Missouri almost never gets too muddy to fish (less than one year in ten, and only for a day or two even then), though it can be very high, and the fishing is typically very good in late May, this is my favorite time on this river.
My favorite fisheries in early spring are the Yellowstone River near Gardiner so long as it is clear, particularly in March when nymphing for pre-spawn rainbow trout waiting to run up tributary creeks can produce great fishing, the Missouri River except during the peak rainbow spawn around the beginning of May, and private lakes. Before mid-April, when access fees jump quite a bit, the Paradise Valley spring creeks are also very good.
Early spring is dominated by three events, all of which can interconnect: the rainbow trout spawn, all fish fattening up after a long, hard winter, and the first insect hatches of the season.
The rainbow trout spawn actually begins in February, but March and April are the most important months and the spawn can extend through May, particularly during high-water years on the Missouri River. While it is not ethical to target the fish as they are actually spawning, and I do not recommend it even if you see others doing so, fishing for pre-spawn and post-spawn rainbows as well as other trout feasting on the eggs of the spawners can be very good. Fish deeper water downstream of the mouths of small streams or downstream of areas of fine gravel on larger bodies of water. This is virtually all subsurface fishing. Use flies that look at least vaguely like eggs: egg patterns, pink scuds, and sowbugs and mayfly patterns that feature orange bead-heads.
When targeting pre-spawn or post-spawn rainbows as well as brown and cutthroat trout fattening up after winter, streamers are always good choices anywhere at this time, as are large San Juan Worms, while stonefly nymphs are good on all rivers that host these insects.
Until late April or early May, midges and Blue-winged Olives are the most likely insects to attract the trout. On tailwaters, you will seldom find vast numbers of fish rising to these insects, but when you do the fishing will be outstanding. On freestone rivers, you’ll often find a few fish rising each day, but almost never large numbers. On spring creeks, the hatches can be much more consistent, usually from late morning through mid-afternoon. Nymphing with patterns imitating these bugs is very consistent anywhere provided the water is clear, while on freestone rivers that are getting muddy, you’re better off with larger nymphs or streamers. By early May, caddis pupae and adult caddis are possible on all streams, but the best hatches occur on the Madison and Yellowstone (if it is clear). On lakes, midge and Callibaetis mayfly hatches are possible by early May, but the best hatches have to wait until late spring.
With the exception of tailwaters and perhaps spring creeks, where water temperatures do not vary throughout the day, it’s unlikely you’ll find good fishing early in the morning or late in the evening during this period. Instead, focus on the middle of the day and perhaps early evening if it’s warm. Insect hatches will be concentrated from mid-morning through mid-afternoon everywhere.
As you have hopefully gathered from the above, early spring IS NOT a great time for dry fly fanatics. There are some hatches, but the best fishing is with streamers and especially nymphs.
Early spring is an ideal time for experienced anglers who don’t mind fishing mostly or entirely with nymphs and streamers in order to target larger trout, either rainbows that are about to spawn or just finishing up or cutthroat or brown trout that are fattening up after a hard winter. Anglers willing to fish wherever weather and water conditions dictate, or even to go and do something else for a day or two if the weather is terrible for fishing, will have the greatest success.
Early spring IS NOT a good time for anglers wanting to fish Yellowstone Park (it’s closed to angling), beginners and novices, “dry-or-die” purists who won’t be happy stripping streamers or watching a bobber, or anglers who are dead set on fishing any specific body of water (with the exception of the Missouri River). It’s also a bad choice for anglers who can’t handle cold/wet weather without getting miserable.
Late spring (late May through June) is the period of high but dropping water on all rivers in the region, the beginning of summer hatches on many warmer rivers as well as all lakes, the opening of the Yellowstone Park fishing season, and the beginning of tourist season. At the start of this period there are only a handful of fishing opportunities, though those that are fishable at this time are generally at or near their yearly best, but more and more rivers become fishable as the month progresses, and the consistency of the fishing generally improves as time goes by.
Late spring is an excellent time for those who wish to visit Yellowstone Park during the summer season but keep away from the worst crowds, as well as those who wish to fish the Missouri River. It is also an excellent period on almost all lakes, with most seeing their best dry fly fishing of the year during calm weather in June.
On the other hand, it’s important to bear in mind that many rivers are almost always out of play until at least the last week of the month, and often even into July. These include the Yellowstone and Lamar Rivers, which are always too muddy in the first half of the month and usually still muddy until at least the 25th. Some stretches of the Yellowstone are also closed until mid-July, as are several less-important fisheries.
June usually features quite pleasant weather, but it has greater swings than July and August see. Early in the month in particular it is quite possible for cold rain or even snow to fall even at low elevations, though it is unlikely to stick save on the highest peaks. By late in the month, daytime temperatures often reach 85-90 degrees at low elevation, but nights are typically quite cool. Rain is common in June at all elevations, particularly early in the month. In sum, anglers visiting in late spring must still be prepared for cold weather, but it’s the exception rather than the rule, and after the middle of the month you’ll be able to fish most locations most days wearing just pants and a shirt, though it’s still a good idea to have a light jacket in addition to the ever-important rain coat.
Water conditions are highly variable in late spring. Large freestone rivers, particularly the Yellowstone and its tributaries, typically see peak runoff near the beginning of this period, then slowly recede through the month. Lower-elevation streams are usually out of runoff by mid-June, and those with geothermal (geyser) inputs experience short runoff periods and are usually fishable sometime between the Memorial Day weekend opener in Yellowstone Park and June 10, depending on how much snow fell the previous winter and how quickly it melted in early May. The high water period on tailwater rivers usually ends by mid-June, after water managers can be sure that the upstream reservoirs will not reach maximum capacity. Note that tailwaters get high, but not muddy, so they remain fishable through runoff. Lakes are generally at their highest in June, whether these are small natural ponds at high elevations in Yellowstone Park or large man-made reservoirs. This doesn’t hurt the “catching,” in fact June offers the best fishing of the year on most lakes, but it can make approaching the lakes on foot treacherous, with muddy and marshy shores and uncertain footing.
All waters drop and clear as late spring progresses. On rivers like the Yellowstone, this is a good thing. On geothermal streams like the Firehole, it’s a bad thing: these rivers (particularly the Firehole) begin to get too warm sometime in the last ten days of the month. On tailwater rivers: it’s a more ambivalent development. The dry fly fishing improves as the water drops, but the nymph fishing gets harder, the fish get spookier, and the rivers start to get weedier.
Yellowstone Park opens to fishing the Saturday of Memorial Day weekend, and the handful of rivers and lakes inside the park that are out of their runoff enough to be fishable at this time are top draws for many anglers. The best and really only bet most years at the beginning of the season is the Firehole River, while the Madison and lower Gardner can also be fishable. All of these rivers get better over the next week or two. The Madison and Gibbon stay good through June, and the Gardner is actually at its best in high summer, but the Firehole can get chancy in the last ten days of the month, particularly in low water years. In dry years, portions of the Yellowstone River near Tower Falls can be exceptional after June 10, but most years the Yellowstone and all its tributaries except one or two tiny creeks and the Gardner River remain too high and muddy through at least June 25. Most lakes in Yellowstone Park can be fishable right out of the gate, but some remain closed and many hike-in lakes are hard to approach due to snow and marshy conditions. Most lakes get much better from mid-June until the end of the month, as the water begins to drop and they get easier to approach.
Outside the park, the Yellowstone remains out of play until June 15 even in the driest years. Average years see it drop into high but fishable shape by the last week of June, while wet years this is more likely July 5-10. The Lower Madison is exceptional through June, though morning fishing is much better late in the month, particularly in dry years. The Upper Madison is chancy for the first half of this period but is often very good in late June. The Gallatin is usually too high until the last week of June. The Missouri is good throughout this period, with the fishing gradually transitioning from mostly nymphing early in the month to dries later. Spring creeks are usually poor in the first half of this period, since hatches are limited, but the world-famous Pale Morning Dun hatches which offer the best dry fly fishing of the year on these waters begin sometime in mid-late June. Lakes outside the park are usually very good in June, particularly private ranch lakes.
Inside Yellowstone Park, my favorite fisheries at this time are the Gibbon River Canyon and assorted small lakes, particularly those that host grayling. During the rare low-water years when the Grand Canyon of the Yellowstone is low and clear enough to fish during this period, it jumps to the head of the list. Outside the park, I like private ranch lakes and the Missouri River.
While the year’s first consistent dry fly fishing gets underway during this period, nymphs and wet flies remain the most productive options. Dries gradually get more important everywhere as the period progresses. In dry years, the upper Madison River and even the Yellowstone can see its Salmonfly hatches begin sometime between the 15th and 20th of June, but the last few days of June extending into mid-July is more likely.
Early on, mayfly nymphs are good choices on any rivers that are more clear than brown, while on dirtier and higher rivers like the Gardner and most of the Madison, stonefly and large attractor nymphs are better. These same nymphs continue to work through the month. Dry mayfly fishing focuses on BWO and PMD on the Firehole early in the period and PMD on other clear rivers as the period progresses. Caddis (including caddis dries) are important on the Firehole, upper Madison in Yellowstone Park, and Missouri throughout this period except perhaps right at the beginning. Soft hackles are particularly good matches for emerging caddis on the Firehole, but they work everywhere these insects are hatching. Large attractor and stonefly dries work sporadically on portions of the Firehole and Upper Madison in Yellowstone Park, and may kick in on the Yellowstone inside and outside the park as well as elsewhere on the Madison late in June if runoff ends at an early or normal time. Classic attractor dry/dropper combinations work well on the Gibbon River by June 10, as well as a few small streams that start becoming fishable around June 20.
On lakes, leeches, San Juan Worms, and soft hackle wet flies imitating emerging midges are the bread and butter flies, but Callibaetis mayfly imitations (nymphs and dries) and large dry midges also work. Some ranch lakes also see good damselfly hatches, though these are rare.
Here's a fishing tip that applies from now through September: Don't hesitate to fish dry flies even if you don't see trout rising. This will be unexpected advice particularly for anglers used to fishing eastern tailwaters. With the warmer water and abundant surface food common during the core of the season here, it is not at all uncommon to find the fish more willing to eat dries than nymphs. The steeper, smaller, and rougher the stream, the more likely you can fish dries all or most of the time. Even portions of the Yellowstone River fall into this category. You are less likely to be able to stick to dries on spring creeks, tailwaters, and lakes. In high summer, you can typically fish dries all day, while in late spring and fall, early morning will probably not produce as much dry fly fishing.
Late spring is a very good time for those who wish to fish in generally comfortable conditions but avoid the heaviest crowds, which are usually present from July through September. It is also a good time for those looking to fish the Missouri and Madison Rivers in a general sense, as well as anglers interested in private lakes. It’s also THE time to fish the Firehole River--it's almost always the period that offers the best fishing of the season on this river.
This is not a good period except in EXCEPTIONALLY dry years for those eager to fish the Yellowstone River and is NEVER a good period to fish the Lamar River or its tributaries Slough and Soda Butte Creek. These bodies of water are essentially never good in June, and are usually completely unfishable until at least June 25 and often much later. Anglers eager to fish spring creeks need to come at the tail end of this period, or earlier or later in the year. This is also a poor period for anglers looking to fish on foot who are not physically fit, since the footing is usually tough due to high water and unsteady banks at this time, even on waters that are more-or-less done with their spring runoff. In addition, crowds are bigger than they are in early spring or in late autumn even if they are smaller than they are in high summer and early autumn.
One note for anglers looking to fish Yellowstone Park at this time: while there’s plenty of fishing to be had, only a couple of fisheries that are ready in late spring offer reliable fishing for good sized (12-18” or better) fish. Most of the lakes and streams instead offer consistent fishing for trout averaging under about 13 inches. If you want big ones and want to fish the park rather than outside it, stick to Yellowstone Lake.
Early Summer, which runs from late June through late July in warm, dry years and from the beginning of July into early August in cool, wet years, is the prime tourist season in the entire Rocky Mountain region. The Yellowstone area is no exception. Both general tourist traffic and angling traffic are intense. This season sees the most consistent weather and water conditions of the entire year, as well as the most consistent fishing and insect hatches. That said, your chances for truly epic fishing are probably better earlier or later in the year, particularly if “epic” for you involves a lack of fellow anglers. In other words, the fishing in July is usually a 7 or 8 out of 10 almost every day for numbers and size of fish, though a 1 in terms of crowds, while earlier or later in the year you might get a 10 or might get a 2 in terms of fishing quality, and the crowds are much less of an issue (particularly from late fall through early spring).
Besides the crowds, there’s one further deterrent at this point in the season: bugs. This is by far the worst point of the year for biting insects except perhaps on the lowest-elevation streams like the Missouri. Both mosquitoes and biting flies can be huge problems, particularly on cloudy, calm days following wet winters. Be prepared to wear long sleeves at all times while fishing (the new technical lightweight fabrics are good), and you may even need a head net during particularly bad years.
As long as you can tolerate heat, early summer weather conditions are the most pleasant of the year. Daytime highs range from the 60s to the 90s, depending on elevation and whether we’re in the midst of a cold spell or not, while nighttime lows range from the 40s at high elevation to the 50s or low 60s at lower elevations. Highs in the 80s and 90s are pretty common except at upper elevations. Brief afternoon thunderstorms are possible, but prolonged rains are rare. Most days will be sunny or partly cloudy throughout the day. That said, you still want a light layer and a rain coat. Though it is possible to wet-wade on almost all waters during this time, I still recommend bringing waders if you have room in your luggage, because we do get occasional cold spells when waders make the difference in staying comfortable or being cold.
Water conditions are likewise at their best of the year: high enough that all rivers lacking geothermal inputs save the Lower Madison remain cold and have hungry fish holding tight to the banks, but low enough that all are almost always out of runoff by July 10 at the latest (June 25 to July 5 more common). With the exception of the Missouri River during dry years, weed growth is at worst an occasional annoyance, and most of the time they won’t be a factor at all. Note, however, that most freestone rivers and even tailwaters following wet years do typically still run high enough that it can be physically challenging wading and getting around the banks, particularly on rough rivers like the Yellowstone, most particularly before the middle of July.
At the beginning of this period, the best fishing flips from the Madison River drainage inside Yellowstone Park and the Missouri and lower Madison River drainages outside it, as well as assorted area lakes, to literally everywhere else. The Yellowstone drainage including its tributaries in the Lamar drainage is my top fishing and guiding area for the remainder of the season, and the upper Madison from Hebgen Lake to Ennis Lake is also good, though an awfully long way from my base of operations in Gardiner. The Firehole and entire headwaters area of the Madison inside the park turn off at this time due to high water temperatures and are not good again until fall. During high-water years, the Madison inside Yellowstone Park may be okay in the mornings in July, but this is rare. Other options inside the park are better.
The following options are particularly noteworthy at this time: The Yellowstone River (note that the backcountry section upstream of Yellowstone Lake and a stretch of a few miles immediately below Yellowstone Lake do not open for the season until July 15), the Lamar River and its tributaries, the Madison River from Hebgen Lake to Ennis Lake, the Gallatin River upstream of Four Corners near Bozeman, the Gardner River, and most small streams, including the Paradise Valley spring creeks, which see their best hatches of the year during the first half of this period.
My favorite fishery in early summer is unquestionably the Yellowstone River, particularly the float stretch of the river between Gardiner and Livingston. The drift boat makes approaching this water much easier than fishing it on foot at this time (since the water is still up in the bushes), and the dry fly fishing is phenomenal. I also like the Yellowstone inside Yellowstone Park, from the mouth of Yellowstone Lake down to the falls after July 15 for big fish, and from the falls to the park boundary for consistent Salmonfly fishing for almost the entire month.
This is prime dry fly season, beginning with the Salmonfly (Giant Black Stonefly) hatches. On steep, well-oxygenated sections of river with large cobble or boulder-strewn bottoms, these hatches are the highlight of the angling year. This hatch of insects as long as your finger is most famous on the upper Madison and Yellowstone Rivers, but it also pops up in shorter sections of the Gallatin, Lamar, and Gardner Rivers at this time. Note that the Lower Madison’s hatch occurs earlier in the year. Most places this is a brief hatch, no more than a week, but both nymphs and dries drive the fish nuts. On the Yellowstone inside Yellowstone Park, the hatch can last in spotty fashion through the entire month of July.
Many other insects also begin hatching in late June or early July, and most years hatches stay strong at least through July and sometimes into early August. On steep, broken sections of stream, it’s often best to use attractor dry flies such as Wulffs, Stimulators, Trudes, and my Clacka Caddis to approximately match many insects at once, usually with an attractor nymph dropper or even a second, smaller dry trailing the first. On flatter streams, including the meadow sections of streams in the Lamar Drainage, much of the Madison, the Missouri, and especially the private spring creeks, it’s usually better to figure out which specific insects the trout are keying upon and to match these exactly.
Besides the Salmonflies, as well as the slightly smaller Golden Stoneflies that hatch at the same time, important stoneflies during this period include the smaller Yellow Sally and the tan and black Midnight or Nocturnal Stone. These insects are generally only important on steep rivers.
Caddisflies hatch from all streams, but are most important on steeper and more-broken streams. They typically draw the most action in afternoon and evening, though egg-laying caddis are possible in the mornings and caddis larvae and pupae (or attractor nymphs that can “push these buttons”) can work at any time. Most caddis that hatch during this period range from #12 to #16 and are tan to brown in color. The tiny black “Micro Caddis” are seldom important.
Mayflies are common on all rivers and on smaller streams that have gravel bottoms. They are more and more important the flatter the stream gradient. Common mayflies in the summer are Green and Gray Drakes, Pale Morning Duns (PMD), and a variety of smaller and less-important species. Of these, the PMD are most widespread. They are small and pale yellow-olive-gray. The Green and Gray Drakes are most common in Yellowstone Park. There are many species which look pretty similar, ranging in size from #10 to #16. All are varying shades of gray and olive, with faint yellow or dark brown markings on some. All mayflies will hatch most abundantly from sometime in early-mid morning until early afternoon. There are sometimes secondary hatches in late evening. Egg-layers can be found in late evening or early morning. These are seldom important. One exception is on the Missouri River, where the tiny black Trico mayfly is most common early in the morning, and for which the egg-laying stage is critical. As with caddis, mayfly nymphs can be important everywhere and all day long, but they’re most important on flatter streams rather than steep rivers or mountain creeks.
Streamer fishing is often overlooked in early summer, but it can be very good at times. This is particularly true of hike-in sections of the Yellowstone River.
Terrestrial insects, including grasshoppers, ants, beetles, and crickets on all waters, and the spruce budworm moth near evergreen trees, begin to work sometime in this period. They start earlier in dry years and later in wet years; they are always most important later in this period and on into late summer.
Expect to find fish in fast, shallow water in early summer. Water temperatures are usually optimal (high-50s or low-60s), flows are powerful in the middle of the river, which pushes fish to the banks, and food is abundant, meaning the fish can hold in fast water and still get plenty to eat to make doing so worthwhile. All of this encourages fish to hold in relatively fast, shallow water, even in little pockets in white water. You will seldom find big numbers of fish in slow, deep, walking-speed water at this time, though big brown trout in particular like to hold in fast, deep water preying upon sculpins and stonefly nymphs.
Early summer is an ideal time for all anglers save those who don’t like crowds (of general tourists and of anglers) and can’t handle biting insects. It’s probably the period that makes the most sense for your first visit to the area, for a variety of reasons: the consistent fishing, the good dry fly fishing, the nice weather, the wide variety of places to fish, and the ease of finding accommodations provided you book ahead of time (since every place to stay is open at this point of the year).
It’s important for me to note that early summer is particularly good for beginning fly anglers, or those with beginners in the group, due to the wealth of small stream opportunities that fish well at this time and can produce plenty of fish for even rookies.
Anglers interested in aggressive hikes, particularly backpacking trips, might want to hold off until late summer. This is particularly true in wet years. The basic reason for this is the potential difficulty in stream crossings since waters are still dropping from runoff during this period, even though all streams are usually low and clear enough to be fishable.
As I’ve noted several times already, crowds are grim at this time of year. This is particularly true on roadside rivers that offer large fish: the Madison downstream of Hebgen Lake, the Lamar River Drainage, and portions of the Yellowstone during its Salmonfly hatch. Soda Butte Creek is often the most-crowded stream within a 500-mile radius at this time, for example. If you don’t like crowds but are up for a hike, don’t mind small streams and small fish, or are planning to float (with the exception of a Salmonfly hatch), you can still find solitude. If you are mobility-impaired but don’t like people, even the bad places to fish near the road might well be too crowded for your taste.
Late summer in many respects continues the trend started in early summer. The weather is generally still nice, the water continues to drop, and the trout continue to look up for dry flies. Overall the crowds of anglers and tourists are slightly smaller by early August than they are in July, and get a lot smaller by August 20 except in Yellowstone Park. The fishing is usually still consistent, though it is not so easy. Except during exceptionally low water years, the trout get in better and better shape as summer progresses, and get prettier due to clearer water. The first hints of fall are in the air, particularly in late August and just before Labor Day, showing in the dry grass, the hints of autumn color in the undergrowth, in the first fall Blue-winged Olive hatches, and in the brown trout starting to become aggressive in preparation for the spawn.
With the exception of early summer, late summer is the most popular season in the region. It’s better for anglers who don’t like crowds. It’s worse for beginners. It’s better for anglers who like fishing terrestrial dry flies. It’s worse for match the hatch fanatics. The bugs are certainly less annoying at this time, and the streambanks are now dry and firm, since runoff is definitively over.
Late summer weather is slightly less consistent than early summer weather. While daytime highs are usually still in the 60s to 90s at all elevations, (70s to 90s most common) nights begin cooling into the 40s and 50s, particularly by about August 20, and some frost is possible in Yellowstone Park. Storms, particularly those associated with early cold fronts, are more common though are still rare. In Yellowstone Park and nearby locations, a significant cold front comes through at some point in the latter half of August about one year in three, bringing snow to the higher mountains and temperatures that don’t break the low 50s even at low elevations. While rare, you should come prepared for this eventuality.
Water conditions are highly variable in late summer and primarily depend on how cold and wet the previous winter and spring were. Flows are always lower at this time than earlier. The question is simply whether they get low enough to cause problems, or merely decline. If not much snow fell and/or it melted early, late summer sees low water and warm water temperatures. Some waters including the Lower Madison regularly see afternoon closures at this time due to low/warm flows, which stress trout. These problems are most acute in early August. Except on the Lower Madison, any restrictions in the Yellowstone area are usually lifted by August 20, due to cooler nights. Note that points further west in Montana, at lower elevations, see much more widespread closures. When the previous winter was wet, or what snow that did stick melted very late, flows remain high enough that there are no temperature issues. Another potential problem in late summer is weed growth. While most common on the Missouri, other large, low-elevation rivers also see substantial weed growth, particularly in dry, hot summers. These weeds make nymph fishing more troublesome though do not generally impact dry fly fishing.
Smaller mountain streams and waters within Yellowstone Park itself (with the exception of the geyser-heated headwaters of the Madison, including the Firehole and Gibbon Rivers) do not see these problems. Rougher mountain streams and rough rivers like the Yellowstone are usually easier to fish in late summer than earlier. I stress “to fish” because the “catching” is usually somewhat more challenging at this time, as the fish get spookier as the water drops and the insect hatches decline; it’s just the wading and walking the banks that get easier.
The best fishing in late summer centers on the Yellowstone River drainage, since this is the highest-elevation and coldest drainage in the region. All waters in this drainage, including the Lamar Drainage, continue to fish well during this period, with only the lower Yellowstone downstream of Emigrant (30 miles north and downstream of the Yellowstone Park boundary) sometimes seeing water temperature issues during the hottest and driest summers.
Other good fisheries include the Madison River between Hebgen Lake and Ennis Lake, the Gallatin River upstream of Four Corners, and the Missouri River below Canyon Ferry Reservoir (the Hauser and Holter tailwaters). The Paradise Valley spring creeks can produce at this time as well, though their insect hatches are not as good as they are in March-May, July, and October-early November. The only lake that is typically good at this time is Hebgen Lake, on the Madison River just west of the Yellowstone boundary.
As noted above, warm water temperatures are a problem at this time. High flows alleviate these problems on all waters. Low flows make them worse. The streams that always or almost always see problems and as such are not worthwhile (or sometimes even OPEN) at this time are the Firehole River, Gibbon River, and Madison Rivers inside Yellowstone Park, the Lower Madison River downstream of Ennis Dam, the Gallatin River and its tributary the East Gallatin downstream of Four Corners, the Gardner River downstream of its hot spring Boiling River, and the Yellowstone downstream of US Highway 89, east of Livingston Montana. These are listed in order from “are always too warm” to “least likely to be too warm.” Other waters are very unlikely to be too warm.
One “niche” fishery worth noting in late summer is the upper Missouri River from Three Forks, Montana downstream to Canyon Ferry Reservoir. While only a marginal trout river in this section (upstream of its famous tailwaters), this stretch of the “MO” is home to vast numbers of big carp. In late summer, it’s possible to sight-fish for these bruisers in shallow water. This is suitable only for advanced anglers, but it can be EXCEPTIONAL if you like carp. They typically run 4 to 10 pounds and you’re unlikely to have much competition besides local guides like me chasing these fish on their days off.
My favorite fisheries for walk-wade fishing in late summer are the Yellowstone River in its canyons, from the Lower Falls down to the point where the river exits the park at Gardiner, and assorted small mountain streams. For floats, I prefer the first 30 miles of the Yellowstone north of the park, basically from Gardiner to Emigrant, over points downstream. The higher the water, the more I like points further downstream as well.
The dry fly fishing remains strong in late summer, but it’s less consistent than earlier save on small mountain creeks. Insect hatches are more fragmentary and the water is simply lower, slower, and clearer than it is earlier in summer, so the fish are somewhat spookier. The top dry fly bite in late summer is on terrestrial insect imitations. Imitations of ants and beetles will bring more strikes on most waters than larger flies, but grasshoppers and crickets are far more popular among anglers. I typically have my clients fish a small grasshopper with an ant dropper at this time; it’s usually my best rig overall in late summer, both for numbers of fish (on the ant) and bigger fish (on the hopper). Large hoppers with nymph droppers can also work well, particularly on larger, rougher sections of river.
In regard to hatches, mayfly imitations are generally more effective than for the remainder of the season (except on the Firehole River, which sees caddis hatches in autumn), since most caddis hatches conclude by the end of July or early August. Mayflies are usually small: Tricos on spring creeks and tailwaters, the smallest Green Drakes (#16) in the Lamar Drainage, and the earliest fall Blue-winged Olives by about August 20 on most rivers. Hatches of all these insects are usually fragmentary, but mayfly nymphs will work anywhere at this time. Stoneflies are usually limited to the Nocturnal or Midnight Stone present on freestone rivers, which can be matched by large tan-gold grasshopper imitations.
One more note about Flies & Hatches: during EXCEPTIONALLY high water years, most recently 2011, all early summer conditions can continue until as late as August 20. Check with me, or any area shop or outfitter, prior to your trip to see if this is the case. These conditions lead to great fishing and far stupider fish than you’ll usually find in late summer, they’re just not expected.
Pay close attention to weather forecasts in late summer. If it’s going to be cool and gray in the afternoons, you’ll want to be fishing at this time. If it’s going to be hot and cloudless, you’ll be better off getting on the water shortly after dawn and quitting when the sun is directly overhead. This is true regardless of water temperature.
When the weather is warm, expect to find the fish in fast water as they were earlier in the summer. Often the sudden drop-offs from shallow water to deep hold more fish than true shallow water at this time, since flows are slower, insect hatches are less intense, and the water is clearer. If early cold snaps have come, especially common late in this period, the fish will begin moving out of faster water to slightly slower areas with a fast walking pace, where they don't have to work so hard to hold position. These areas will generally still be highly-oxygenated (turbulent or choppy), however.
As I noted in the Weather and Water Conditions section, weeds can be a problem at this time. Check your flies regularly: trout don’t like salad on their steak.
With the exception that the fishing is usually not quite as consistent, particularly on bigger and more-famous waters as opposed to mountain creeks, fishing in late summer is generally suitable for the same anglers as fishing in early summer. The trout still like dries, all of the same waters are generally good, and the crowds are almost as heavy until about August 20 in a general sense, and throughout the period in Yellowstone Park.
There are some categories for whom late summer is better. Anglers who are unsteady on their feet will find walking and wading all streams easier at this time, due to reduced flows and sturdier bottoms and stream banks, since bottoms and banks have had more time to stabilize since the high water of runoff. Late summer is also better for high mountain backcountry anglers, since stream crossings are easier at this time and all waters have dropped from runoff even in the wettest years.
Anglers interest in match the hatch fishing can do as well in late summer as earlier, but they should expect to work harder for their trout since the insects are smaller and their hatches are more fragmented, and because the water is lower, slower, and clearer, so the fish are spookier. On the other hand, anglers who like terrestrials will do much better in late summer than earlier. Plenty of beginner options remain available in late summer, but the consistency of beginner fishing is not quite as good, again since the fish are a bit spookier.
Early Fall is a time of transition. On hot days, the fish act like it’s summer. On cold days, they act like it’s late fall. When the weather is in-between, it’s a mix of the two. Regardless of the day-to-day weather, the brown trout start to get very frisky at this time, the fall hatches begin in earnest, the terrestrial bite becomes shaky (particularly after September 20 or so), and water temperatures drop out of the danger zone, if they ever got there. The water is now low and clear as glass everywhere, leading to spooky fish, though often spooky fish that feed aggressively.
Just about everything in the Yellowstone area fishes well in early fall except most lakes and smaller creeks, though which days in early a fall a given body of water will produce best varies. The Firehole might be great during an early cold snap in September but very tough on a bright, warm day late in the month, for example. As such, early fall is a good time for anglers willing to fish where conditions dictate, using the tactics conditions dictate.
Here’s one thing early fall is not: a time to find solitude on popular rivers, particularly walk-wade rivers in Yellowstone Park. Many anglers come shortly after Labor Day and are shocked to see summer crowds. This is now to be expected. Everyone trying to get away from the summer crowds by coming a few weeks later creates a new crowd in the first half or three weeks of September. If you want to really shed crowds, come after September 20 or even in October. There’s also sometimes a “sweet spot” between the summer crowds and the early fall crowds. This usually occurs in the last ten days of August. River floats also tend to be less busy at this time. For whatever reason, it’s the technical walk-wade rivers near the road that are emphatically crowded
As noted above, weather and water conditions can be all over the map in early fall, and the calendar has little to do with determining the weather. It is not uncommon for it to be colder in the first week of September than the first week of October, for example. Suffice it to say that you should be prepared for everything after about August 20. The highs might be in the 30s or the 90s, the lows in the teens or the 60s. The daily range is particularly broad in early fall: it’s not at all unusual for nights to produce a little light frost even at low elevations, while daytime highs might flirt with 75 or 80 degrees. In other words, pack layers. Also bring a warm hat and gloves from here on out. One constant of fall weather is that the region typically sees at least one multi-day storm. This storm brings snow to the high mountains and cold rain with daytime highs that might not crack 40 degrees in the valleys. This storm is most common within a few days of the fall equinox, but it can happen any time.
Water conditions are more consistent save when heavy rains raise levels on freestone rivers and streams for a day or two. They are typically low everywhere throughout this period, and when the high country begins to freeze consistently every night, even freestone rivers like the Yellowstone that usually carry a hint of color turn clear as glass. Water temperatures now drop into the 50s everywhere, with 40s possible on cold mornings on smaller streams. These dropping temperatures begin to push hatches and fish activity towards midday and the afternoon, with morning fishing limited to streamer and nymph fishing for the brown trout beginning their spawning runs, which don’t like bright sun. These dropping temperatures (as well as the less-consistent weather) are universally good for larger rivers, geyser-heated waters, and spring creeks. They’re not good for small mountain streams. Small streams only remain fishable until the first cold snap. After that, they’re usually too cold for the remainder of the season, and even larger freestone streams like the Lamar Drainage in Yellowstone Park will become challenging during cold spells.
The top fisheries in early fall can include every fishery in the region with the exception of small creeks. With the exception of extremely hot or cold weather, all other fisheries should fish acceptably well throughout the period. This is one reason why early fall is a great period for anglers who wish to fish a variety of waters. When the weather runs to one extreme or the other, the quality fisheries will likewise slant one direction or the other. Cold and wet weather will make large rivers, streams that host brown trout spawning runs, geothermally-influenced waters, and lower elevation waters in general fish better than others. Hotter, drier weather will make freestone streams within Yellowstone Park (the Lamar) and the Yellowstone River fish better than other options, and are really your only chance if you do wish to fish small mountain streams. Ideal weather for fall fishing consists of temperatures in the 50s with cloud cover. Such conditions will make everything except the little creeks red hot.
While small high-elevation lakes are typically not good choices in early fall, low-elevation ranch ponds begin to kick into gear once weather cools, and lakes that hold brown trout will see these fish gathering in inlet areas in preparation for the spawn. Hebgen Lake just west of the Yellowstone Park boundary is the most-famous example.
My favorite early fall fisheries are the Gardner River, for early fall-run browns, and the Yellowstone River. On the Yellowstone, the hike-in streamer fishing is excellent in the canyons, while on the float stretch, I like the entire river from Gardiner downstream past Big Timber, since the crowds are now gone and water temperatures are ideal. Since the crowds are lower at this time, larger fish are somewhat more eager to eat tiny dry flies than they are earlier in the season.
With a couple exceptions, tactics vary in early fall depending on the weather. I’ll cover the things that DON’T change first.
Targeting early fall-run browns first thing in the morning or late in the day, in both cases when the sun is not yet on the water, using large stonefly and attractor nymphs (smaller, rougher rivers and streams) and streamers (larger float rivers) can produce a handful of larger fish regardless of weather conditions at this time of year. This is usually not a numbers game and is not a good choice for rookies and novices.
Larger freestone streams and river typically see at least fragmentary Blue-winged Olive and other small or medium-sized mayfly hatches throughout this period around midday. When hatches are limited as they are during bright weather, attractor dry flies like Purple Haze Parachutes or Purple Hazy Cripples (one of my patterns, usually better than the parachute) work better than hatch-matching dries. When the weather is ugly and hatches are more intense, either fish a hatch-matching dry and one of the purple bugs together, or fish a larger and more visible hopper or attractor dry (or a larger mayfly pattern if larger mayflies are hatching) with either the hatch-matching dry or the purple fly.
When the weather is ugly, particularly ugly and cold, stick to larger rivers (freestone or other), spring creeks, or geothermally-influenced rivers. Larger rivers will all see mayfly hatches under such conditions, though tailwater rivers will typically see smaller Pseudo mayfly (tiny Blue-winged Olive) hatches rather than the full-sized Baetis BWO during this period. Larger freestone rivers (Yellowstone and Madison) see Tan Drake (Drake Mackeral) hatches in addition to BWO hatches during bad weather, and fragmentary hatches of other larger mayflies (Western Cahill, Mahogany) may also occur during bad weather in the last few days of August through early October. Streamer fishing is also good on larger rivers. On spring creeks, look for midge or Pseudo hatches. On geothermal rivers, most particularly the Firehole, the White Miller caddis common in June are important now as well. There may be some mayfly hatches but these are more important later in the fall. Ugly weather is also a good time to focus on targeting browns and the occasional fall-run rainbow using big nymphs and streamers, even during the middle of the day.
When the weather is bright and sunny, freestone rivers may still produce fishable mayfly hatches (see note on BWO above). Terrestrials (hoppers and ants) can be expected to work on these rivers at least as well as mayflies when the weather is warm/sunny. Tailwaters may see midge or Trico hatches, but these are rare. Nymphing or perhaps terrestrials are better choices. Fishing will be challenging and usually limited to sight-nymphing on spring creeks, while geothermal rivers are probably not worth your time unless they hold fall-run browns (and then only early/late in the day). Smaller freestone rivers like the Lamar and Gardner continue to fish well on terrestrials at this time, though nymphing is probably a more consistent option now (whereas dry flies or dry/dropper were at least as good during summer). Hatches are more likely in the Lamar Drainage during bright weather than under gray skies in the fall provided temperatures are not over 70 degrees. These include assorted Green and Gray Drakes from size 10 all the way down to 16 (full size Green Drakes are larger, Flavs are smaller, the flies are identical except in size), BWO, black or cream midges, and Tan Drakes. Even when afternoons are warm, the best hatch activity on all freestone streams and rivers is likely to occur around midday or even in the afternoon.
Early fall is a great time of year for any experienced angler provided they are willing to put up with larger than expected crowds in Yellowstone Park (particularly on roadside easy-access fisheries like the Lamar and its tributaries, the headwaters of the Madison, and the Firehole), are eager to fish for trout that are a bit spookier than they are earlier in the season, and are willing to visit fisheries and use tactics that make sense depending on weather and water conditions. It is a particularly good time for those who like Blue-winged Olive hatches, as this is prime time everywhere except spring creeks and tailwaters for these insects in Yellowstone Country. This is also a good period for anglers who want to spend some of their time hunting a handful of larger trout with nymphs and streamers but also want consistent fishing for numbers of trout part of the time.
Early fall is not such a great time for anglers who have specific fisheries or tactics in mind, whatever these may be, beginners, anglers who like small stream or alpine lake fishing (though larger and lower-elevation lakes are okay), anglers who come expecting low crowds without hiking, or anglers who like tailwaters but prefer to fish dry flies. It is also a poor time for anglers who prefer to fish in comfortable weather; sometimes early fall DOES see comfortable weather, but on most prime fisheries at this time, the better fishing is when the weather is cold and wet.
To anglers from warmer parts of the country, the period running from sometime in the last few days of September or early October through the middle of November will feel more like winter. Cold and wet weather is now the norm, and snow is very possible at any time. If you are contemplating coming during this period, this is the one factor you MUST be willing to accept.
Late fall is brown trout season. Targeting these fish as they prepare to spawn is the number one option in the region at this time. Some options for dry fly fishing for other species still exists, but for most visitors, it’s a secondary option. The overall numbers of fisheries that make sense from a consistency perspective declines steadily through the period, and crumbles once Yellowstone Park’s season ends at sunset on the first Sunday in November. Crowds are generally gone except on the most-famous brown trout rivers (particularly the Madison). Elk are bugling. Aspens and cottonwoods turn gold in October, then fade to brown and bare limbs late in October. It’s a great time to be here if you like hunting larger trout and can handle the weather.
Weather conditions can be warm, bright, and sunny, or it can be snowing sideways with temperatures below zero. Neither extreme is good for fishing. The best days will occur when daytime highs range from the high-30s into the fifties, under cloudy skies, with little or no wind. Average highs are in this ballpark, however it’s more commonly sunny and windy than cloudy and calm. Rain is more common at valley level than snow at least until the beginning of November, but mountain snows stick around from now until spring, and even in the valleys it will snow enough to stick around for several days from time to time.
I cannot overstate how important it is to be prepared for bad weather in late fall. Just about every year there will be at least one heavy snow event with Arctic temperatures even at low elevations sometime between the first of October and the middle of November, and more often there will be several lighter snow events as well. These are most common towards the end of autumn, of course, but they can happen at any time. I have seen temperatures fail to get out of the single digits on October 1, for example. Bring layers, warm gloves and hat, a winter survival kit for your vehicle, and waders and raingear without leaks!
Except immediately after storms, the water will be low and clear at this time. Even after storms, it is unusual for even mud-prone rivers like the Yellowstone to get dirty, since higher elevations usually see snow rather than rain in the fall, which knocks loose less sediment. The water will also be cold. No high-elevation (over about 6500 feet) waters save geothermally-heated rivers like the Firehole are worth fishing except during exceptional warm spells from now until June. The water is just too cold. Even on low-elevation and geothermal waters, the water will be cold enough that falling in can be hazardous, so have spare dry clothes available.
Without exception, the top fisheries in late fall are those that stay warm the longest and those that hold fall-run brown trout (and some rainbows). Most waters that fish well once October rolls around are both.
Low-elevation rivers, whether freestone or tailwater, are the most productive fisheries in a general sense. These include all “big names:” The Yellowstone, Missouri, Madison, and Gallatin all fall into this category, as do most other famous rivers in Montana outside of my operations area. All large rivers in the area hold fall-run brown trout, and since they’re at lower elevations and bigger than other fisheries, they don’t get as cold as quickly and so also maintain insect hatches for at least part of this period, and often right until the end if the coldest weather holds off.
Geothermal waters and spring creeks are also good, since the warm(er) water inputs keep temperatures much more stable year-round. For dry fly fishing, check the Firehole or the Paradise Valley spring creeks, where this is prime BWO time. For bigger browns, the lower Gibbon, lower Firehole, lower Gardner, and Madison within Yellowstone Park are good through the first Sunday in November, while the spring creeks continue to fish well for them even into the winter.
Small ranch lakes are the other good option at this time, particularly during October. As the water temperatures begin to drop, the weeds that are so annoying in these lakes much of the season die back and the trout that live in these lakes (of whatever species) feed aggressively on leeches and other large fare in preparation for winter. Without exception, the top ten “big number” days my clients have had on these lakes have occurred in late fall.
Waters that are seldom worth fishing in late fall include all small streams except spring creeks as well as high-elevation rivers, including the Lamar System in Yellowstone Park. You will still see tons of people fishing this water at this time as long as the weather is tolerable, but they will seldom be doing any good. The Yellowstone inside Yellowstone Park is also questionable if the weather has been good, but if you want to catch cutthroats, it’s probably your best option.
My favorite waters to fish and guide in late fall are the lower Gardner River in Yellowstone Park, the Yellowstone River float stretches outside the Park, and private lakes.
On private lakes, fish leeches, streamers, San Juan Worms, and other large fare. Fish these flies relatively slowly, either using a slow strip retrieve or under an indicator. Ledges, the edges of weed beds, and wind-swept shorelines are good places to start.
On flowing waters, you basically have two options, both of which will work to a greater or lesser degree depending on the water in question, the weather, and your goals. The first option is matching the insects common in late fall both on the surface and subsurface. The second option is to target fall-run browns and the smaller number of fall-run rainbows that come with them, using nymphs and streamers.
The primary late fall insects on all waters are Blue-winged Olives, both Baetis and the tiny Pseudos, as well as midges, which at this time are usually dark in color with very pale gray wings. On geothermal waters, you will still see some blond White Miller caddis as well, though these peter out through late fall. When you don't see fish rising, fish subsurface flies that match these insects. Look for walking-speed water that's at least two or three feet deep everywhere except spring creeks and geothermal rivers like the Firehole. The fish may be in faster water on spring creeks, tailwaters, and geothermal rivers. Everywhere else they like it slow. Rising fish are most likely to be found in areas bugs collect: foam piles, eddies, and slow current seams. The colder the water, the more likely rising fish will concentrate on the side of the river receiving more sun, usually the east side since most of our waters run generally north. Rising trout are unlikely save around midday, and I suggest fishing dries only when you see risers from now until late spring.
When targeting fall browns, fish deeper and/or more turbulent water to avoid harassing actively spawning fish. The full spawn begins around mid-October and continues through the middle of November or later. A good rule of thumb is to avoid fishing areas with gravel bottoms that are less than four or five feet deep, since such areas are prime spawning habitat. You will find plenty of fish staging downstream of these areas, either fish that have not started spawning yet or those that have finished (as well as resident fish eating the eggs of spawners).
Good flies for targeting these fish are egg patterns, stonefly and large attractor nymphs, and streamers and large steelhead-style wet flies. Nymphs and eggs will produce more fish. Streamers and large wet flies often produce bigger fish and harder strikes. The best areas are walking-speed runs with boulder-strewn bottoms that are at least waist-deep, with six or eight feet deep even better. You can also "intercept" fish by hitting the deepest, slowest areas within long runs of shallow, fast water, though these can be hard to pinpoint. On larger float rivers, either swing streamers on foot in the big runs or "strip and rip" them if you're fishing from a moving boat. By late fall, you can fish for running browns and 'bows all day regardless of weather, but the very best weather for targeting these trout is when it's gray and spitting rain or snow. This also keeps crowds away. The crowds of anglers targeting these trout can be quite intense in some areas, particularly the Madison near Yellowstone's west entrance and the Lewis River in the central part of Yellowstone Park.
Late autumn is prime time for big fish fanatics who can tolerate cold and ugly weather. Early spring is probably just as productive for large fish (though not browns), but more waters are open and fishing well in late fall than spring, and water conditions seldom get muddy. Beginners need not apply. Neither should people who dislike fishing subsurface flies, since the dry fly bite in late fall is much less consistent than it is earlier in the season. This is also a poor time for anglers who like to use a wide range of tactics, since as noted above only a handful of techniques tend to produce. In addition, this is actually a poor time for anglers who like to hike to fish. There are plenty of options for walks of a half-mile or so to get away from the road, but besides the Lewis River, there are no hikes over about a mile that are likely to produce as well as options closer to the road.
By early November, the crowds have vanished from the Yellowstone area with the exception of the Missouri River. By the middle of the month, they’re gone here too. For good reason. Fishing opportunities rapidly decline, as does the quality of the weather. Heavy snow is possible as early as late September, but it’s the rule rather than the exception after the middle of November. Most people who come to the Yellowstone area in the winter come either to play in the snow, on skis, snowboards, or snowmobiles, or to watch wildlife. Nobody comes just to fish. That said, there’s certainly fishing to be done, and it can be quite good for a few hours around midday provided it’s warm enough you can tolerate it, but it’s still just for diehards. You’re unlikely to share the water with anyone but locals.
Note that the Yellowstone National Park fishing season closes at sunset on the first Sunday in November. As such, all winter fishing is outside the park.
Weather in the winter ranges from bad to worse. While it might occasionally reach 50 degrees even in January at low elevations, more-typical temperatures range from around 0 degrees on up to the mid-30s, and it can get a lot colder. When it does get warm and sunny, the nice temperatures and sunshine are usually accompanied by horrific winds out of the southwest. These are particularly common in November. Arctic blasts with temperatures well below zero are most common in December and January, but can happen at any point in the winter. The heaviest snowfalls are usually in January at lower elevations, while the mountains actually see falls just as heavy in March and April. Snow is usually on the ground at least in windblown drifts (and often accumulates everywhere to depths of feet) at all locations starting sometime in late November or early December. It sometimes melts out at low elevations by late February, but not always, and it can always snow again. Snowshoes can be helpful in reaching some good winter fisheries, particularly the Madison River between Hebgen and Quake Lakes.
Water conditions in November sees all rivers at their lowest flows of the year. This makes walking and wading easy, though of course a spill is far more dangerous at this time than at other times. Water temperatures range from “crunchy” (ice) on freestone rivers, particularly from December through early February, to about 40-45 degrees, with the warmest temperatures on the Paradise Valley spring creeks. Look for water temperatures in the 38 degree range or higher before going fishing, as trout do not feed well at colder water temperatures. January and February see warmer water temperatures than December, due to the longer hours of daylight.
“Top Fisheries” is a bit of a misnomer. It’s more like “only fisheries.”
As noted, Yellowstone Park is closed to fishing in the winter. Lakes all freeze by mid-November and stay frozen until March. The only large rivers that are consistently good all through the winter are the Missouri River downstream of Canyon Ferry Dam (including the famous tailwaters below Hauser and Holter Dams) and the Lower Madison River below Ennis Dam. Even downstream portions of these waters can see ice during late December and January. Otherwise, the top bets through the entire winter are the Paradise Valley spring creeks and other spring creeks.
Freestone rivers can see fair fishing on warm days through November, but most portions of them will see slush or full-blown ice in December and January, often extending until the middle of February. Isolated stretches of all of these rivers can fish well through the winter, particularly portions near the mouths of hot springs or spring creeks, but these are often chunks of river no more than a couple hundred yards in length. If you do fish freestone rivers in December and January, be very wary walking and wading: ice shelves may break under you and drop you in the river, and drifting ice sheets have knocked anglers in and killed them.
Better fishing on freestone rivers, basically the Yellowstone, Gallatin, and the Madison between Quake Lake and Ennis Lake, begins in late January or early February when more light falls on the water, but the spring creeks and tailwaters remain better choices.
My favorite winter fisheries are isolated portions of the Yellowstone River near hot spring inputs, particularly the section right through Gardiner which receives warm water from the Gardner River (which has some hot springs on it), and the Paradise Valley spring creeks. If I lived closer, I would fish the Missouri quite a lot at this time as well.
Early winter may see the same tactics that worked in late autumn continue to work for a little while. This is especially true on low-elevation tailwaters (the Missouri and Lower Madison) and spring creeks. Some BWO and midge hatches may occur, fishing streamers relatively slowly can move larger fish, and there may still be enough brown trout spawning for their brethren or other trout that are sitting downstream of them to be willing to eat egg patterns. This fishing ends by the 10th of December or so even on the spring creeks, the places it lasts longest.
After this point, tactics diverge between spring creeks and other (colder) rivers. On the spring creeks, fish midge larvae and pupae, mayfly nymphs, San Juan Worms, and perhaps streamers all through the winter. On calm, cloudy days you may find a few fish rising to midges or even tiny Blue-winged Olive mayflies. By late January, some rainbows may start moving into the creeks in preparation for the early spring spawn, so egg patterns will start drawing fish. The fishing can often be quite good on the creeks in the winter, and rates are lower than at busier times of year.
On all other bodies of water, the name of the game is finding water moving at a slow walking pace that is between three and perhaps eight feet deep. Such areas are winter holding lies and are the only areas where trout will be found consistently. Top flies are usually small. Midge pupae and mayfly nymphs are good on all bodies of water. Sowbugs and scuds or Czech nymphs that resemble these crustaceans, all usually pink in color or at least containing pink “hot spots,” often work better on tailwaters. In February, egg patterns may begin to work. Stonefly nymphs can work on freestone rivers, while on tailwaters you might dead-drift a streamer. On warm, calm days, you might find limited-duration midge hatches on all rivers. In these situations the fish will move into slightly faster and shallower water, though they’ll almost never be in water that’s moving at more than a fast walking pace or shallower than two or three feet. Hatches will be most prominent near the mouths of spring creeks or geothermal (hot spring) inputs, such as near the mouth of the geothermally-heated Gardner River where it dumps into the Yellowstone right in the town of Gardiner.
Except possibly on the spring creeks, where midmorning might offer good fishing, there’s no point in getting out on the water before about noon during the winter. The best fishing will conclude by 3:00 or 4:00PM.
With the exception of locals, nobody should come just to fish in the winter. Guides would love it if more did, but there just aren’t enough opportunities.
That said, if you’re coming primarily to ski, snowmobile, or wildlife watch, there ARE some opportunities to get out. Just bring plenty of warm clothes, fingerless gloves, and your midge and small fly boxes. Fishing can be solid in the winter, it’s just hard both in a tactical sense and on the body. Brrrrr…
Walter Wiese is licensed to operate on all waters in Montana under general regulations, Yellowstone Park, and the Madison River in Montana. He is Montana Outfitter #22001, Yellowstone Park CUA holder 426SSF, and Madison River SRP Holder #297.
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