Arroyo Valle near Livermore
Arroyo Valle · Sierra / West · USGS gage 11176500
Trout (marginal) (summer mean 20.4°C — trout, warm in summer).
Water
76°F
Flow
9 cfs
Air
64°F
Sky
0%
Pressure
29.72 in
Wind
6 mph
Predicted hatches · 2026-08-04
PredictedHopper / TerrestrialsAcrididae (grasshoppers)0.95
Predicted by conditions; no reports yet. water 24.3°C (76°F) is cooling past the prime band (17-24°C); peak season; 8 days sustained ≥14°C; 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.