Roaring Fork River above Difficult Creek near Aspen, Co.
Roaring Fork River · Rockies · USGS gage 09073300
Coldwater (summer mean 12.3°C — prime coldwater).
Water
38°F
Flow
24 cfs
Air
43°F
Sky
100%
Pressure
29.99 in
Wind
8 mph
Predicted hatches · 2026-10-30
PredictedMidgeChironomidae0.50
Predicted by conditions; no reports yet. water 3.1°C (38°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
PREDICTED from the first-principles model only. Report-confirmed signal (fly-shop & forum reports) is the next milestone.