Yellowstone River Fishing Report

This Yellowstone River fishing report is valid from September 2, 2025 until a substantial cooldown occurs. Unfortunately, this does not look imminent.

Fishing was good with some cooler water and gray skies midweek last week, but a return to 80+ afternoon air temps and water peaking in the 67-71 degree range depending on section, accompanied by bright sun, has made things difficult again. They will remain so-so at best until we get some consistent cooler water and/or clouds. The water is just too low for bright sun and warm air temps to result in good fishing. We want 58 degrees and drizzle, now that it’s fall according to the “old time” calendar. What do I mean? September used to require waders and raincoats more often than not, and produced good hatches. Now that it’s functioning like an extension of late summer, the fish and bugs are in a holding pattern, and none of them like it.

Early mornings might be slow, since the water temperature is going through huge swings daily. Fish streamers if you start at dawn. Starting around 9:30 or so, expect nymphs to produce some trout in Livingston and below. Upstream, they will produce 95% whitefish except in Yankee Jim Canyon. The dry fly bite has been best at midday and in early afternoon. Small peach hoppers trailing ants and copper-colored #16-18 attractor dries have been best. In the clouds (if you get any) go with purple-purple instead.

We suggest quitting east of Grey Bear by 2:00 and everywhere else by 4:00 until temps cool off. That’s another change. It wasn’t long ago that we were already meeting clients at 9:30AM and quitting at 6:00PM in September, and seeing our best fishing during the warmest part of the day. Not anymore; we need a cold rainstorm for that.

• Hatches: A few caddis, a few midges, a few Tricos, a few of this or that other mayfly. None need be imitated right now. A few Tan Drakes and BWO are stumbling around and will get more important as the days pass, but we need cooler water temps and gray skies for really good hatches of these fall insects.
• Dry Flies: #16 Hazy Cripples (copper and purple are both working), cinnamon and bicolor ants (both parachute and flying), Missing Link, small oddball hoppers like Bob Hoppers. Some bigger fish are eating big flesh or yellow hoppers in the heavier stretches that see less pressure. Flesh/peach has been our best hopper color all summer.
• Nymphs & Wets: #16-18 PT Spankers, #16-18 silver or gold Lightning Bugs and Spankers, #16-18 Rainbow Warrior, #16-18 Pheasant Tail or Frenchie, #18 Radiation Baetis. Upstream from Livingston, expect mostly whitefish on nymphs.
• Streamers: Small jig-style sculpins and TJ Hookers under indicators, serving mostly as weight for your smaller nymphs. The streamer bite this year has been “meh” at best due to the low water. The “strip and rip” bite won’t kick in until we get some cooler weather.

Learn more about fishing the Yellowstone River (in Montana).

Info about our float trips, a majority of which take place on the Yellowstone.

Info about our Montana walk & wade trips, which in winter and early spring take place on the Yellowstone.

Yellowstone River Streamflow Data

Sudden spikes on the Corwin Spring gauge suggest mud is on the way. Fish further downstream. Also check the gauges on the Yellowstone Park page for the Lamar River and Gardner River, as these also show mud coming into the Yellowstone. When water temps are peaking over 22 degrees Celsius (a bit over 70F), we suggest quitting by 2:00PM. Mandatory closures begin when flows are hitting 73F (22.75C).

The graphs are presented from upstream to down. For more granular data, check out the new USGS Montana Streamflow Data pages. It is not possible to embed this more in-depth information on external websites.

Also keep an eye on the following water temperature gauges. These areas are downstream of Livingston and are more prone to getting too warm in late summer. Flow data is not available at these sites, but there’s not a lot of change downstream of Livingston during fishing season, since all tributaries on this reach are pretty small.

Yellowstone River Webcam

This camera (courtesy Montana Whitewater) is prone to failure and may operate intermittently.

Yellowstone River Fishing Report – Links

• Lamar River, Gardner River, and Shields River streamflow data: Sudden flow spikes in these waters will bring mud into the Yellowstone, the Gardner first.
• Gardiner, Corwin Springs, Emigrant, Livingston, Big Timber, and Columbus weather forecasts. Watch the wind speeds and avoid floating Livingston-Columbus when east winds are forecast.
• Gardiner Webcam This raft company webcam gives a good sense of Yellowstone River level and clarity for the Upper River.

Note: We update our general fishing report far more often than our fishery-specific reports like this one, especially between November and April.