Snake River Above Reservoir, Near Alpine
Snake River · Rockies · USGS gage 13022500
Coldwater (summer mean 16.0°C — prime coldwater; very large river (9,660 cfs)).
Water
56°F
Flow
4,220 cfs
Air
44°F
Sky
0%
Pressure
30.03 in
Wind
4 mph
Predicted hatches · 2026-09-15
PredictedSpotted / Summer CaddisHydropsyche spp.0.38
Predicted by conditions; no reports yet. water 13.5°C (56°F) is warming toward the prime band (14-19°C); shoulder of the season; 7 days sustained ≥12°C; watch evening, last hour of light.
flies: Elk Hair Caddis #14-16, Iris Caddis, X-Caddis
PredictedMidgeChironomidae0.21
water 13.5°C (56°F) is cooling past the prime band (1-10°C); shoulder of the season; 7 days sustained ≥0°C; watch midday, especially cold months.
flies: Zebra Midge #18-22, Griffith's Gnat, Disco Midge
PREDICTED from the first-principles model only. Report-confirmed signal (fly-shop & forum reports) is the next milestone.