North Fork Bull Run River Near Multnomah Falls
North Fork Bull Run River · Pacific NW · USGS gage 14138900
Coldwater (summer mean 10.8°C — prime coldwater).
Water
54°F
Flow
25 cfs
Air
84°F
Sky
94%
Predicted hatches · 2026-06-16
PredictedGreen DrakeDrunella spp.1.00
Predicted by conditions; no reports yet. water 12.4°C (54°F) sits in the prime band (11-15°C); peak season; 3 days sustained ≥10°C; watch midday, often cloudy.
flies: Green Drake Parachute #10-12, Cripple, Hares Ear #10
PredictedMidgeChironomidae0.30
water 12.4°C (54°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
PredictedSalmonflyPteronarcys californica0.24
water 12.4°C (54°F) is warming toward the prime band (13-16°C); peak season; watch late morning through evening.
flies: Rogue Foam Salmonfly #4-6, Chubby Chernobyl, Pat's Rubber Legs
PREDICTED from the first-principles model only. Report-confirmed signal (fly-shop & forum reports) is the next milestone.