Snake River Below Flat Creek, Near Jackson
Snake River · Rockies · USGS gage 13018750
Trout (marginal) (summer mean 16.8°C — trout, warm in summer; very large river (8,690 cfs)).
Water
57°F
Flow
4,060 cfs
Air
43°F
Sky
0%
Pressure
30.05 in
Wind
4 mph
Predicted hatches · 2026-09-15
PredictedSpotted / Summer CaddisHydropsyche spp.0.50
Predicted by conditions; no reports yet. water 14.0°C (57°F) sits in 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
PredictedMidgeChironomidae0.17
water 14.0°C (57°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.