Share your catch

Snake River (South Fork) Fishing Report

Updated Fri, Sep 4, 2026 from live gauge and weather data

The South Fork: Idaho's big cottonwood tailwater, thick with native cutthroat and heavy browns under the Tetons' far side.

2/5
Slow. Work for them.Conditions favor short windows and patient fishing.
Flow
6,930 cfs
Air / High
78 / 80 F
Wind
SSW 11 mph

Sources: USGS gauge 13032500, Open-Meteo, solunar calculated for these coordinates.

Satellite view
Friday
4
September 2026

Today's Fishing Report

Generated this morning from live readings: gauge, weather model, sun and moon. A fresh report is published here every morning.

2/5Slow. Work for them.Conditions favor short windows and patient fishing.

Snake River (South Fork) feels the season turning: shorter days, grouping fish. The river is running 6,930 cfs, dropping and clearing. Today brings clear skies, wind SSW around 11 mph, rising pressure near 1006 hPa and a high of 80. Water sits around 54 F for the season (estimated). With the last quarter, the solunar majors run 5:39 AM-7:39 AM and 5:39 PM-7:39 PM: the windows to build the day around.

The plan, species by species

Rainbow troutGood

Blue-winged olives and midges on soft seams; streamers on overcast days move the better fish.

Brown troutGood

Pre-spawn aggression: this is streamer season for the fish of the year.

Tomorrow: Similar at 82 F. The solunar majors shift about 50 minutes later.Next report: Sat, Sep 5, 6:30 AMHow this report is made →

Water and weather

Live readings from Snake River near Irwin.

Flow, last 30 days

USGS gauge 13032500.

7,7779,48011,1836,930 cfs08/0508/1508/2509/04

Right now

Latest readings

Air temp78 F
High / Low80 / 51 F
WindSSW 11-21 mph
Pressure1006.0 hPa, rising
Sky / Rain0% cloud, 1%
Sunrise / Sunset06:52 / 19:55
MoonLast Quarter, 50%
Water temp (seasonal)~54 F est.

Bite planner

Hour-by-hour bite forecast for today. Tap a bar to see why.

5 AM8 AM11 AM2 PM5 PM8 PMsunrisesunset

Next 7 days

Tap a day for the detailed outlook.

Fri Sep 4 · Clear, 80/51 F, wind 14 mph, rain 1%

Fair or better. A 14 mph breeze puts a working chop on the banks it hits: fish the wind-blown side.

Species guide

The species that matter on Snake River (South Fork): seasons, structure and how to fish each one. Today's ratings live in the report above.

Rainbow trout illustration

Rainbow trout

Best: Apr-Jun, Sep-Oct

The workhorse of western rivers: riffles, seams and dry-fly eats. Blue-winged olives and midges on soft seams; streamers on overcast days move the better fish.

Brown trout illustration

Brown trout

Best: Sep-Nov

Wary, predatory and nocturnal by preference. The big ones eat streamers. Pre-spawn aggression: this is streamer season for the fish of the year.

When to come: the Snake River (South Fork) calendar

Activity by species and month, and how the water warms through the year. Tap any cell.

Species activity by month

1 = slow, 5 = peak. Current month highlighted.

J
F
M
A
M
J
J
A
S
O
N
D
Rainbow trout
Brown trout
SlowPeak

Water temperature through the year

Typical surface temperature for this water type; today is around 54 F (estimated, not a reading).

30405060JanMarMayJulSepNovSep, ~54 F now

Angler reports

Real reports from real anglers, reviewed before publishing. The water log below tracks each day automatically.

No angler reports yet this weekBe the first: your report helps every angler who checks Snake River (South Fork) today, and we feature the best catch of the week.

Water log, last days

Auto-logged from live data
Thu, Sep 3

3/5 Fair. Fish the windows. A steady pattern: dawn and dusk carry the day. Rainbow trout led the card at good. High of 75 F, wind to 10 mph.

Wed, Sep 2

3/5 Fair. Fish the windows. A steady pattern: dawn and dusk carry the day. Rainbow trout led the card at good. High of 76 F, wind to 15 mph.

Tue, Sep 1

3/5 Fair. Fish the windows. A steady pattern: dawn and dusk carry the day. Rainbow trout led the card at good. High of 75 F, wind to 10 mph.

Where roughly, what depth, what bait. Skip anything you want to keep secret.
Only used to send you this water's report each week. No spam, ever.

Before you go

License

Idaho requires a valid fishing license for adults. Buy online from the state agency; one-day options exist for visitors.

Regulations

Idaho license. Cutthroat: catch-and-release. Rainbows: no limit, harvest encouraged: check IDFG South Fork rules.

Access

Launches: Palisades, Spring Creek/Heise, Byington, Lorenzo, Menan; wade access at every ramp and the canyon trails.

About this water

64 tailwater miles from Palisades Dam to the Henrys Fork confluence, eastern Idaho. The cutthroat stronghold.

Fishing Snake River (South Fork): the full guide

The cottonwood giant

The South Fork of the Snake runs from Palisades Dam through a cottonwood corridor that holds one of America's great trout populations: 4,000-plus fish per mile: native Yellowstone cutthroat, rainbows, hybrids and browns that grow past 20 inches on the tailwater's steady bounty. It is Idaho's flagship river and a conservation battleground where the cutthroat still hold.

Riffle-and-side-channel game

The river fishes big: drift boats run the main channels while the side channels and riffle corners hold the wade fishing. Summer's salmonfly-and-golden parade (late June-July) marches upstream from Heise; PMDs and caddis carry the mornings; late-summer mutant stones bring the year's strangest dry-fly fishing after dark falls close.

Cutthroat first

Management protects the natives: rainbows are unlimited-harvest (the state wants them out of the gene pool), cutthroat are release-only. Learn the difference cold: orange throat slash, spotting pattern. Anglers are the management tool here: keep rainbows, kiss cutthroat goodbye gently.

Canyon to valley

Three characters: the upper river (Palisades to Heise) with its canyon and the famous bankside stonefly fishing; the middle's braided cottonwood maze (the wildlife corridor: eagles, moose, otters); the lower canyon toward Menan with big browns and fewer boats. October streamer fishing for pre-spawn browns is the connoisseur's week.

Common questions

Why should I keep South Fork rainbows?

Hybridization threatens the native cutthroat: IDFG removes rainbows and asks anglers to help: no limit, any size. The cutthroat you release today is the fishery's future.

When is the South Fork salmonfly hatch?

Late June through mid-July, moving upstream from Heise toward the dam: the canyon banks crawl with size-4 naturals. Big foam tight to the willows: the takes are visible from the rower's seat.

Is fishing good at Snake River (South Fork) right now?

Check the daily report at the top of this page: it is regenerated every morning from live data. Today's read: Slow. Work for them. Conditions favor short windows and patient fishing.

Nearby waters

Blackfoot Reservoir38 miSnake River40 miHenrys Fork46 miJackson Lake47 miFremont Lake77 miHenrys Lake89 mi
Share your catch