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Mckenzie River below Payne Creek, near Belknap Springs

Mckenzie River · Pacific NW · USGS gage 14158740

Coldwater (summer mean 6.3°C — prime coldwater).

Water
42°F
Flow
190 cfs
Air
54°F
Sky
11%
Pressure
29.95 in
Wind
4 mph
Predicted hatches · 2026-09-15
PredictedMidgeChironomidae0.50
Predicted by conditions; no reports yet. water 5.8°C (42°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
PredictedBlue-Winged OliveBaetis spp.0.45
Predicted by conditions; no reports yet. water 5.8°C (42°F) is warming toward the prime band (6-11°C); shoulder of the season; 8 days sustained ≥4°C; watch midday, especially overcast afternoons.
flies: BWO Sparkle Dun #18-22, RS2, Pheasant Tail #18

PREDICTED from the first-principles model only. Report-confirmed signal (fly-shop & forum reports) is the next milestone.