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Big Hole River below Mudd Creek near Wisdom

Big Hole River · Rockies · USGS gage 06024540

Trout (marginal) (summer mean 19.3°C — trout, warm in summer).

Water
77°F
Flow
269 cfs
Air
66°F
Sky
0%
Pressure
29.89 in
Wind
5 mph
Predicted hatches · 2026-07-31
PredictedHopper / TerrestrialsAcrididae (grasshoppers)0.40
Predicted by conditions; no reports yet. water 25.2°C (77°F) is cooling past the prime band (17-24°C); shoulder of the season; watch warm, breezy afternoons.
flies: Morrish Hopper #8-12, Chubby Chernobyl, Dave's Hopper

PREDICTED from the first-principles model only. Report-confirmed signal (fly-shop & forum reports) is the next milestone.