White River At Calico Rock
White River · Ozarks · USGS gage 07060500
Trout (marginal) (summer mean 16.4°C — trout, warm in summer; very large river (35,800 cfs)).
Water
69°F
Flow
21,200 cfs
Air
77°F
Sky
1%
Predicted hatches · 2026-06-16
PredictedHexagenia (Hex)Hexagenia limbata0.87
Predicted by conditions; no reports yet. water 20.7°C (69°F) sits in the prime band (19-23°C); peak season; 2 days sustained ≥18°C (wants 3); watch after dark — the famous night hatch.
flies: Hex Dun #4-8, Hex Nymph, Hex Spinner
PredictedLight CahillStenacron / Stenonema0.77
Predicted by conditions; no reports yet. water 20.7°C (69°F) is cooling past the prime band (16-20°C); peak season; 8 days sustained ≥15°C; watch dusk.
flies: Light Cahill #14-16, Cream Cahill, Cahill Spinner
PredictedSlate Drake / IsonychiaIsonychia spp.0.50
Predicted by conditions; no reports yet. water 20.7°C (69°F) sits in the prime band (16-21°C); shoulder of the season; 8 days sustained ≥14°C; watch afternoon/evening; nymphs crawl to shore to emerge.
flies: Isonychia #10-12, Slate Drake, Leadwing Coachman
PredictedSulphurEphemerella dorothea / invaria0.43
Predicted by conditions; no reports yet. water 20.7°C (69°F) is cooling past the prime band (15-19°C); peak season; 8 days sustained ≥13°C; watch evening, the last two hours of light.
flies: Sulphur Comparadun #16-18, Sulphur Spinner, Pheasant Tail
PredictedSpotted / Summer CaddisHydropsyche spp.0.22
water 20.7°C (69°F) is cooling past the prime band (14-19°C); shoulder of the season; 8 days sustained ≥12°C; watch evening, last hour of light.
flies: Elk Hair Caddis #14-16, Iris Caddis, X-Caddis
PREDICTED from the first-principles model only. Report-confirmed signal (fly-shop & forum reports) is the next milestone.