Big Wood River At Hailey Id Total Flow
Big Wood River · Rockies · USGS gage 13139510
Coldwater (summer mean 15.4°C — prime coldwater).
Water
57°F
Flow
163 cfs
Air
38°F
Sky
39%
Pressure
29.90 in
Wind
7 mph
Predicted hatches · 2026-10-30
PredictedMidgeChironomidae0.17
water 14.0°C (57°F) is cooling past the prime band (1-10°C); shoulder of the season; 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.