Idaho ·
Henrys Fork Fly Fishing Report - May 31, 2026
HENRYS FORK
ReportMAY 31 — JUN 7, 2026
🌊
Flow
—CFS
🌡️
Water Temp
—
☀️
Weather
36–66°F
Light Rain
💧
Clarity
Clear
Check post-storm
USGS gauge data is currently unavailable for the Henrys Fork; river conditions are based on guide reports and NOAA weather only. Overnight rain and Sunday cloud cover are setting up ideal BWO emergence conditions, with a sunny clearing on Monday offering the best all-around window of the weekend.
What's Working — Hot Flies
Parachute - Blue Wing Olive #22
#22
Egan's CDC Rainbow Warrior #22
#22
Olsen's Peacock Blowtorch Barbless #22–24
#22–24
Juju Baetis Tungsten #22
#22
Top Secret Baetis #16
#16
Egan's Silver Bullet - Baetis #14
#14
Olsen's Pheasant Tail Nymph Doppleganger Brown Barbless #24–20
#20–24
Tungsten Split Case Nymph - PMD #20
#20
Olsen's Straggle Stone Brown Barbless #12–32
#12
Tungsten Pat's Rubber Legs - Tan & Brown #6
#6
Tungsten Jig Bugger - Olive - Barbless #14
#14
Corn-fed Caddis (CDC) Olive #20
#20
Hatch Chart
| Insect | Size | Activity | Prime Time |
|---|---|---|---|
| Blue-Winged Olive (Baetis) | #18–22 | 🟢 Peak | 10 AM – 3 PM; best on overcast days |
| Midge | #20–22 | 🟢 Consistent | Early morning & evening |
| Salmonfly (subsurface nymphs) | #4–8 | 🟡 Building — lower canyon | All day; nymphs crawling to bank edges |
| Golden Stonefly Nymph | #8–12 | 🟡 Increasingly Active | All day — fast seams & pocket water |
| Western March Brown | #12–14 | 🟡 Active (lower sections) | Late morning |
| PMD (Pale Morning Dun) | #16–20 | ⚪ Approaching — early nymphs | Warm late afternoons in tailouts |
Best Time Window
- Sunday 9:30 AM – 2:00 PM: Overcast skies and light rain create prime BWO emergence conditions — expect blanket hatches and rising fish in slower water adjacent to fast seams
- Sunday Evening 6:00 – 8:00 PM: Midge activity picks up as temps stabilize; fish the slower tailouts and flats with small nymphs and emergers
- Monday 10:00 AM – 1:00 PM: Sunny clearing to 66°F will trigger a compressed but intense BWO and early PMD window — best all-around dry-fly opportunity of the weekend
Guide's Tip
From the benchSunday's overcast skies and light rain are a gift for BWO fishing — don't sleep in. Get to Box Canyon or Hatchery Ford by 9:30 AM and watch the slower water adjacent to fast seams for the first noses. If fish are sipping but refusing your dry, drop to a CDC emerger or WD-40-style pattern fished just under the film on 7X tippet — that's where the biggest fish are often feeding. Monday's sunny forecast and 66°F high will push hatch activity earlier and compress it, so be on the water by 10 AM before the sun gets high and fish drop back to the bottom. In Box Canyon, adjust your weight constantly — depths vary dramatically run to run, and your nymph needs to be ticking the bottom to draw strikes from the big rainbows holding in the boulder gardens.
Main Species
Rainbow Trout
Brown Trout
Yellowstone Cutthroat Trout
