Flathead River At Columbia Falls
Flathead River · Rockies · USGS gage 12363000
Coldwater (summer mean 13.8°C — prime coldwater; very large river (17,700 cfs)).
Water
42°F
Flow
3,640 cfs
Air
34°F
Sky
79%
Pressure
29.98 in
Wind
2 mph
Predicted hatches · 2026-11-01
PredictedMidgeChironomidae0.50
Predicted by conditions; no reports yet. water 5.6°C (42°F) sits in the prime band (1-10°C); shoulder of the season; 8 days sustained ≥0°C; watch midday, especially cold months.
flies: Zebra Midge #18-22, Griffith's Gnat, Disco Midge
PredictedBlue-Winged OliveBaetis spp.0.46
Predicted by conditions; no reports yet. water 5.6°C (42°F) is warming toward the prime band (6-11°C); shoulder of the season; 8 days sustained ≥4°C; overcast skies favor it; watch midday, especially overcast afternoons.
flies: BWO Sparkle Dun #18-22, RS2, Pheasant Tail #18
PREDICTED from the first-principles model only. Report-confirmed signal (fly-shop & forum reports) is the next milestone.