2026 Yellowstone Area Streamflow and Fishing Predictions

Introduction

Winter snowpack and how this snowpack melts from April through mid-June are the most important factors in determining summer water levels and fishing conditions. They’re also important factors in “quality of life” aspects of summer fishing, such as how much wildfire smoke can be expected in late summer.

This is our post about snowpack and expected conditions for the 2026 season. This post will be updated every couple of weeks as conditions change, until roughly June 20 to July 1, when we expect all area fisheries to be finished with the spring melt and ready to go for the summer season.

Updated on Feb 22, 2026

The Extremely Short Version

We have a low, rotten snowpack that is largely limited to high elevations. We anticipate an early beginning and end to the spring melt. Low, warm water is likely or certain in late summer. This means that widespread 2:00PM and some complete fishing closures are also likely to certain, with the most widespread closures in place between July 20 and the end of August. Almost universal 2:00PM fishing closures are possible if runoff starts extremely early and summer is extremely hot/dry, such as we saw in 2021.

The best summer fishing conditions are likely to be found from roughly June 20 through July 20, weeks ahead of schedule. We suggest coming earlier than you would during a “normal” year, if possible.

The whole West outside of our operations area is actually in even worse shape, so wildfire smoke from distant fires is likely to be present and may be intense (actually good for the fishing, not for the views or the breathing). Local fires may also be bad, though this depends on lightning rather than just dryness.

Despite everything else, we are actually in better shape than anywhere else in the West. If I was a guide in Colorado, I’d be trying to line up a construction job, for example.

Current Conditions

• Fall generally saw normal temperatures and a lot of moisture (both rain and snow). December saw extremely high moisture, but very high snow levels due to warm temperature. January and early February saw record warmth and dryness. The middle and beginning of the latter part of February have been near-normal for both temperature and precip.
• Snowpack in the Yellowstone River basin is below normal, at 96% of normal, but higher than any other “trouty” basin in the Rocky Mountains or anywhere else in the West at large.
• Snowpack in the Madison and Gallatin basins is below normal, but still higher than most basins in the West.
• Precipitation during the 2026 water year (which starts Nov 1) has been good, at at least 108% of normal.
• Regardless of location, the snowpack is limited to high elevations. High-elevation snow sensors report above normal snow depth and water content, while areas under 8000 feet are below normal to severely below normal.

The really striking fact about all of the above is that the snowpack is limited to high elevations. We have nothing at valley level here in Livingston, little to no ice on area rivers, and not much even at the lower elevations of the local ski areas in the 6200 to 7500-foot range. It’s only when you go higher than that that we have something resembling a normal winter.

Outlooks for Late Winter and Spring

Here are some bullet points about outlooks for the remainder of winter (through March at low elevations and April at high elevations) and spring (April through mid-June). These outlooks come from the National Weather Service Climate Prediction Center.

• March is forecast to have equal chances of normal, above normal, and below normal precipitation in the area. We are right on the edge of where above normal temperatures are favored (points to the south of us are forecast to see above normal temps and below normal precip).
• The three-month rolling outlook for March through May is calling for equal chances of normal, above, and below normal for both precip and temperatures.
• Later in spring and in summer, an El Nino is forecast to form. This leads to increased likelihood of above normal temperatures and below normal precip for the entire Rocky Mountain West and Pacific Northwest until fall.

What Does the Above Mean, Generally Speaking?

This is the important part for most readers. This is what the above is likely to mean for fishing conditions during our runoff season and most of peak season, roughly April 20 through sometime in September (hopefully early-mid September), after which day-to-day weather such as the onset of fall rains and mountain snows is a bigger factor than weather from the previous winter/spring.

• With little low-elevation snowpack, early pulses of runoff during March and early April warm spells are unlikely to muddy area rivers for a day or two at a time, as they often do following more typical winters.
• Because of the warm winter, the high-elevation snowpack has never “set up” in a deep freeze. This makes it likely to begin melting early, and to melt hard and fast when it melts.
• The above means that we expect the heavy spring runoff to begin earlier than usual. April 20 to May 5 seems like a likely range for the beginning of the melt.
• The melt will end early. The precise dates depend on the watershed, when exactly the melt starts, and how warm it is from the onset of the melt until mid-June, but “two to three weeks before runoff usually ends” seems likely everywhere.
• This will lead to many more options in June, particularly the middle and end of June.
• On the other hand, it will lead to low, warm water everywhere between July 20 and the onset of the fall rains in September, and this warm water may even start earlier on some low-elevation watersheds, especially those with a lot of irrigation drawdowns and/or hot spring inputs.
• Widespread 2:00 and some complete fishing closures are basically certain in late summer. The timing of these closures will depend on when prolonged hot weather hits. Most or all major fisheries are likely to be impacted by them. The Firehole, Gibbon, and Madison Rivers in Yellowstone Park and the lower Madison River near Bozeman will see the earliest closures (perhaps as early as June 20-25 for the YNP waters). The Yellowstone River, upper Madison River and small streams in MT will hold on the longest into late summer, with the small streams in MT unlikely to see any closures. 2:00PM closures on the Yellowstone are 50/50 and less likely upstream from Livingston.

When Will Runoff Begin and End? When Will Waters Get Too Warm?

As noted, all of this depends on weather that hasn’t happened yet, as well as the snowpack. So the ranges given here are broad, and the likelihood of closures in particular is very hard to estimate. Take the following as a rough planning guide only at this point.

Specific rivers, river systems, or sections of rivers are listed in order of “end of runoff,” earliest to latest, more or less. “Classes” of waters such as small streams are discussed at the end of the following list.

• Firehole, Gibbon, and Madison in YNP: These waters open May 1 this year, for the first time ever. They are likely to already be in what runoff they will undergo. We do not expect these waters to ever become unfishable, with the exception of the Gibbon in its headwaters upstream from Norris Campground. This area will be too cold (but maybe not too high) until June 5-10. Everything else will be very good in May and taper off quickly in early June. The Firehole in particular is likely to be too warm to fish well or ethically in the afternoons between June 5 and 10 and at all June 10-15. The Gibbon below Norris and the Madison will hold on another week. The Gibbon above Norris Campground will be best June 15 through July 15. All of this water is likely to close completely by early July, with the exception of the upper Gibbon. Even the Firehole tributaries usually close along with the mainstems. Closures will likely continue until Labor Day.
• Lower Madison River: The Madison from Ennis Dam to Three Forks will not see an unfishable runoff, though the area downstream of Cherry Creek may be too murky to fish anything but nymphs for a few days in mid-late May and after early June rains. The best fishing will occur in the latter half of May and early June. Heavy crowds of kayakers and tubers will start impinging no later than June 10, and June 20 is likely to see the water too warm to fish well/ethically. 2:00 or complete closures will likely begin July 1-10 and continue until early September.
• Upper Madison River: The upper Madison may see a few days of “too muddy” around June 1, but only a few. Expect the water to drop enough to fish dry flies between June 10 and June 20. Closures upstream from Ennis are unlikely, but the “braids” area between Ennis and Ennis Lake will probably see 2:00 closures starting somewhere around July 20. You might need roller skates on the bottom of your drift boat to float this water in August and early September.
• Boulder River: Unfishable runoff will begin sometime in the first three weeks of May and last for two to three weeks except during cold snaps, when the river will drop to fishable levels. The best fishing here for boaters will begin June 10-20 and continue for two or three weeks. It will get too low to float except in an ultralight raft between July 5 and July 15. Closures are unlikely, but from an ethics standpoint they should be put in place when the water is super skinny in late July and August. The upper river will fish fine all summer, since it’s basically a creek.
• Stillwater River: Push everything I said about the Boulder back by about a week. This one may or may not see 2:00 closures by July 20-25, but it probably should in its lower reaches, since temps yo-yo hugely on this stretch and might be 60 first thing in the morning and 73 by 3:00. Flows will probably get too low to float around August 20.
• Gardner River: Reminder that this one is open year-round now. It will probably begin the heavy runoff between April 20 and May 5 and remain unfishable except during cold spells until June 10-15. The best fishing will occur from the end of runoff until July 4 below Boiling River and until July 20 above. The headwaters (small stream and small fish) areas will start fishing in mid-June and be best before July 20. 2:00 closures are likely below Osprey Falls beginning around July 20 and continuing until late August. Even if the closures are not implemented, the water from Boiling River to the Yellowstone confluence is almost always too warm to fish well/ethically from late July until early September, and it’s still very weedy for several weeks after that.
• Yellowstone River – Grand Canyon: The Grand Canyon and Upper Yellowstone (above the Falls) area is likely to run comparatively higher than anything else in our operations area, since it is fed almost entirely by the highest mountains where snowpack is actually above normal. It seems likely this water will be in runoff on the park opener in late May and remain too high and murky (if not actually filthy) until at least June 15 and maybe as late as June 20. This assumes that Yellowstone Lake doesn’t filter a lot of this runoff. If it does, this water will clear much sooner, possibly right at the beginning of the park season. This one is much harder to predict than anything else, because the snowpack is decent in the headwaters but very low on the tributary drainages that feed this section. In other words, it’s all over the place here, vs either low (most places) or above normal (further up the Yellowstone). 2:00PM closures will only be implemented on this section if almost all flowing water in Yellowstone Park gets them, since Yellowstone Lake helps to moderate temperatures here in something like a tailwater effect. The best fishing will be in late June and July, but this one holds on better in August and September than the Black Canyon downstream.
• Yellowstone River – Black Canyon: The Black Canyon (from the Lamar confluence to the park entrance at Gardiner) will be in runoff on the park opener. It will clear enough to fish between June 5 and June 25, probably somewhere right in the middle. This is very early, unlike the Grand Canyon, because the Lamar System is much lower on snow than the Yellowstone mainstem’s headwaters, and the Lamar tends to govern the Yellowstone’s color downstream of the confluence. This water runs warmer than the Grand Canyon, but 2:00 closures are also less likely here than many other places. If they come in, it will be after July 20. The best fishing will be in July.
• Yellowstone River – Montana: Runoff is likely to begin very early here, probably between April 15 and May 5. Absent extended cold spells in May and early June, it will be unfishable for roughly six weeks after the onset of the heavy melt. It is likely to come back into shape between June 5 and June 25. We ran our first float trip here on June 19 last year and could have done it two days earlier. We bet we’ll be able to get on the water a couple days earlier yet this season. The best fishing will be for a month to six weeks after the river clears, then turn on again in September as the light gets flatter. 2:00PM closures are very likely between July 20 and August 25, particularly east of Livingston. The last time we had 2:00 closures over the whole length of the Yellowstone in Montana was 2021, and before that 2007. East of Livingston sees them far more often. Even absent closures, it seems certain you’ll want to quit fishing at 2:00 or 3:00 most days from mid-July through Labor Day due to tough fishing in warm water and under bright sun in late afternoon.
• Lamar River System in YNP: Will almost certainly be muddy on the park opener. Will clear between June 10 and the end of June, with June 20 seeming very likely for everything and June 10-15 possible for Slough Creek and the Lamar Canyon. Slough runs clearer than the rest of the system, and the Lamar Canyon has enough boulders and other structure than nymphing with big stoneflies can work well even if the water is murky. 2:00 closures are possible between July 20 and the end of August, but will likely only be implemented if all flowing water in the park gets them. The best fishing will be in July. Late August and September will be very difficult and crowded, with extreme low water. We always hate fishing this water in September due to the skinny water, crowds, and torn-up fish, and this year will be even worse.
• Yellowstone River – Lake to Falls and Headwaters: This water opens for the season on July 1 and will be low and green if not crystal clear yet. The best fishing will happen in July. Closures are unlikely here unless all flowing water in the park gets them, since this water never gets over about 65 degrees given its high elevation and the moderating effects of Yellowstone Lake.
• Other Rivers in the Region: The Gallatin River upstream from Gallatin Gateway will come into shape in mid-June. It will be fine temperature-wise all summer, but probably very low and weedy from late July onward. It’s always crowded. Downstream of Gateway and particularly downstream of Four Corners, irrigation drawdowns will prompt 2:00 closures by mid-July and probably full closures in August. The Jefferson River will blow out in mid-late April and clear in early June. It will get too warm to fish almost immediately thereafter, with 24-hour closures almost certain in August. To be honest, it amazes us that any trout still survive in this river given how much irrigation water is taken from it. 75+ degree water is common here. The Lower Beaverhead and Big Hole Rivers will see extreme low water by late July and full 24-hour closures are likely from late July until late September, particularly on the Big Hole. The Missouri River below Hauser & Holter dams (the tailwater “trouty” stretches) will be low and weedy all season, but will avoid 2:00PM closures unless we see an extreme early start to runoff and extended extreme heat. Word is they fished absolutely awful from August through mid-October in 2025 due to low water and extreme weed growth. We’d expect the same this year, but at least the water will probably be cool enough…
• Small Streams: Low-elevation small streams like the East Gallatin will see limited runoff. There just isn’t enough snow in their basins. They will get some combination of too low and too warm by mid-June. Higher-elevation but gentle creeks such as those on the Central Plateau in Yellowstone Park will get low/warm/clear enough to fish sometime in the first half of June and will be best for the month thereafter. Closures are unlikely on anything in YNP unless all flowing water gets them, but by August some of these creeks will have less water in them than what runs down your gutter when you’re washing your car. The rough and tumble mountain streams will come in in the last week of June, roughly, with level rather than clarity the governing factor. July and maybe early August will offer the best fishing on most. Closures are unlikely on any of these in Montana. In YNP, those feeding the Firehole/Madison/Gibbon and lower Gardner will share the closures their parent rivers get. Others will only see 2:00 closures if all flowing water in the park gets them.
• Spring Creeks: The Paradise Valley Spring Creeks are protected from the worst impacts of low (or high) water since they are spring-fed. The best periods as always are late March through about April 25, June 20 through July 20, and late fall. The June 20 through July 20 period is booked solid already and won’t have wide availability even in 2027, since this is always peak season. Closures won’t happen unless there’s widespread fire or something of that nature that shuts down all outdoor recreation (this only happened in 1988).
• Ranch Lakes: Very limited ice cover means that these will become fishable by early April this year, assuming the access roads aren’t muddy. Snowdrifts on the ranch roads will not be a factor this year unless we get late blizzards. The best fishing will be before mid-June, after which all will quickly get too warm and weedy.
• Low Elevation Public Reservoirs: Those at lower elevations have been basically ice-free at least time-to-time all winter, which is unprecedented. If there’s enough ice-free water when you’re here, go fishing. The trout will be in the shallows where the sun warms the water. The best fishing on these will conclude by early May in most cases, and by early June the water will be too warm and best left to the perch/walleye anglers and swimmers.
• High-Elevation Lakes, Including the Beartooth: Those in YNP will probably be ice-free by the opener in late May, though the hike-in lakes (such as Grebe) may be slogs to reach due to mud and water on the trails, though probably no snow or not much. The best fishing on these will be from about June 5-10 for about a month to six weeks. Late summer is unlikely to see closures, but will probably see tough fishing as the fish go deep to beat the heat. On the Beartooth, expect most lakes to be ice-free by mid-June and to be accessible by late June. The best fishing will occur in July. August might see some tough fishing even at these above-treeline lakes if summer comes early and the waters warm enough to send the trout deep.

Other Key Dates

This is sort of a grab bag for when we expect various season highlights to occur, based on expected water conditions. They are in no particular order.

• Firehole River Caddis: Mid-May through early June.
• Yellowstone River Mother’s Day Caddis: Probably washed out by runoff. If not, the last few days of April and first few of May.
• Lower Madison Mother’s Day Caddis: May 10 through May 25 or June 1. Flows should permit good dry fly fishing this year, so long as it isn’t too hot and bright.
• Yellowstone River Salmonflies (Montana): Expect a very fishable but very fast-moving hatch this year. It will be begin between June 10 and June 25, probably around the 15th.
• Yellowstone River Salmonflies (YNP): A few may pop near the small hot springs around Tower Falls around June 10-15, but June 20-25 for the Lower Black Canyon and June 25 to July 4 elsewhere will be heavier.
• Lamar System Green Drakes: The full-size #10-12 Drakes (Drunella doddsi) might start the last week of June. The first two weeks of July will be best. The smaller #14 Drakes (D. flavilinea or D. coloradensis) will shade in around July 10 and dominate into September. A few of the doddsi return in mid-September, but Hecuba and a few D. grandis are more common then.
• Yellowstone River “Chubby Rubby” Fishing: This big dry and big nymph bite will be best in late June and the first week of July.
• Yellowstone River Hoppers & Ants: This bite will start very early, probably by July 10 and maybe even sooner. July will be best for hoppers, especially larger ones. We may or may not see decent hopper fishing in August and September. Often low water sees a much better bite on ants and tiny mayfly-type attractor dries.
• Boulder River Float-Fishing: The Boulder always has a short window. June 10-20 through July 4-10 seems likely this year, depending on exactly when runoff begins and how quick the water drops.
• Yankee Jim Canyon Floats: I don’t do Yankee Jim with clients until flows are under 5000cfs. 4000cfs is better. 3000cfs is probably optimum, with fishing gradually getting slightly harder once things get below 2500, but the canyon remains good no matter how low it gets. I had good hopper fishing on October 1 at under 1000cfs in 2025. Expect 5K around June 20 to July 1, 4X June 25 to July 4, and 3K July 15-20.
• 4th of July Crowds? Sometimes the 4th of July holiday and weekend aren’t too crowded. This year crowds will likely be awful since flows will allow fairly easy floating and wading and the 4th itself falls on a Saturday. I’m going to do my best not to run float trips on the 4th and 5th this year, and my trips on the 3rd will start and end early. The Lower Madison will be a JOKE SHOW.
• Most Likely Period for Widespread Fishing Disruptions Due to Heat & Low Water: July 20 through August 25, though challenging fishing in terms of techniques, crowds, and spookiness of the trout will continue until the fall rains hit in mid-late September.