Clearwater River near Peck
Clearwater River · Rockies · USGS gage 13341050
Coldwater (summer mean 11.8°C — prime coldwater; very large river (13,200 cfs)).
Water
57°F
Flow
12,800 cfs
Air
91°F
Sky
0%
Predicted hatches · 2026-06-16
PredictedGreen DrakeDrunella spp.1.00
Predicted by conditions; no reports yet. water 13.9°C (57°F) sits in the prime band (11-15°C); peak season; 4 days sustained ≥10°C; watch midday, often cloudy.
flies: Green Drake Parachute #10-12, Cripple, Hares Ear #10
PredictedEastern Green DrakeEphemera guttulata0.82
Predicted by conditions; no reports yet. water 13.9°C (57°F) is warming toward the prime band (14-18°C); peak season; 2 days sustained ≥12°C (wants 3); watch evening; the spinner (Coffin Fly) falls at dusk.
flies: Green Drake #8-10, Coffin Fly Spinner, Drake Emerger
PredictedSalmonflyPteronarcys californica0.80
Predicted by conditions; no reports yet. water 13.9°C (57°F) sits in the prime band (13-16°C); peak season; 2 days sustained ≥12°C (wants 4); watch late morning through evening.
flies: Rogue Foam Salmonfly #4-6, Chubby Chernobyl, Pat's Rubber Legs
PredictedGolden StoneHesperoperla / Calineuria0.78
Predicted by conditions; no reports yet. water 13.9°C (57°F) is warming toward the prime band (14-18°C); peak season; 2 days sustained ≥13°C (wants 3); watch afternoon and evening.
flies: Chubby Chernobyl #8-10, Yellow Stimulator, Pat's Rubber Legs
PredictedSpotted / Summer CaddisHydropsyche spp.0.47
Predicted by conditions; no reports yet. water 13.9°C (57°F) is warming toward the prime band (14-19°C); shoulder of the season; 2 days sustained ≥12°C; watch evening, last hour of light.
flies: Elk Hair Caddis #14-16, Iris Caddis, X-Caddis
PredictedMarch Brown (Eastern)Maccaffertium vicarium0.47
Predicted by conditions; no reports yet. water 13.9°C (57°F) is warming toward the prime band (14-18°C); shoulder of the season; 2 days sustained ≥12°C; watch sporadic through the day, midday into afternoon.
flies: March Brown #10-12, Hare's Ear, Spinner
PredictedPale Morning DunEphemerella spp.0.43
Predicted by conditions; no reports yet. water 13.9°C (57°F) sits in the prime band (13-18°C); shoulder of the season; 2 days sustained ≥12°C (wants 3); watch late morning to early afternoon.
flies: PMD Comparadun #16-18, Sparkle Dun, Pheasant Tail #16
PredictedSulphurEphemerella dorothea / invaria0.39
Predicted by conditions; no reports yet. water 13.9°C (57°F) is warming toward the prime band (15-19°C); peak season; 2 days sustained ≥13°C (wants 3); watch evening, the last two hours of light.
flies: Sulphur Comparadun #16-18, Sulphur Spinner, Pheasant Tail
PredictedMidgeChironomidae0.17
water 13.9°C (57°F) is cooling past 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.