Idaho
Henrys Fork at Ashton
Current River Rating
Fair · 52
Conditions are mixed. Review the details below before heading out.
Scores are model-specific and are not directly comparable across water types.
Partial water evidence · Medium confidence
Should I Go?
Wait
Timing Outlook
This timing outlook is informational only; current river conditions remain Fair.
Why
- Very clear skies may make trout more cautious in shallow water.
- Water temperature is unavailable.
Favorable Factors
- Recent precipitation has been light.
- Light wind should make casting and boat control easier.
Timing Evidence
Dawn low light is favorable.
Current Readings
- Flow
- 1740 CFS
- Gage Height
- 4.05 ft
- Water Temperature
- Not available
- Observation Time
- Sep 5, 2026, 7:15 AM
Updated recently · USGS station 13046000 · Direct monitoring location
Readings from past 7 Days
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Historical readings are provided for context. Readings outside the current freshness window are not used to rate current conditions.
Better Nearby Options
Checking nearby StrikeTracks waters…
Preliminary guidance only. Always assess current weather, access, water depth, current speed, and your own ability before entering the river.
Changing Conditions Advisory
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Weather Near Gauge
Current Weather
Clear
Temperature
56°F
Feels like
50°F
Wind
8 mph E
Wind gust
14 mph
Current precipitation
0.00 in
Updated
Sep 4, 2026, 11:15 PM
Recent Rainfall
Estimated precipitation near this gauge
Last 6 hours
0.00 in
Last 24 hours
0.00 in
Last 48 hours
0.00 in
Little recent rainfall near this river.
Next 24 Hours
Sat 2 AM
Clear
Temp 54°F
Chance 1%
Precip 0.00 in
Wind 7 mph
Sat 6 AM
Clear
Temp 47°F
Chance 2%
Precip 0.00 in
Wind 6 mph
Sat 10 AM
Clear
Temp 57°F
Chance 1%
Precip 0.00 in
Wind 0 mph
Sat 2 PM
Clear
Temp 76°F
Chance 0%
Precip 0.00 in
Wind 13 mph
Sat 6 PM
Clear
Temp 79°F
Chance 0%
Precip 0.00 in
Wind 11 mph
Sat 10 PM
Clear
Temp 60°F
Chance 0%
Precip 0.00 in
Wind 9 mph
Four-Day Forecast
Sat, Sep 5
Clear
High 79°F / Low 46°F
Chance 2%
Precip 0.00 in
Max gust 25 mph
Sun, Sep 6
Drizzle
High 82°F / Low 52°F
Chance 45%
Precip 0.04 in
Max gust 28 mph
Mon, Sep 7
Drizzle
High 67°F / Low 49°F
Chance 83%
Precip 0.23 in
Max gust 34 mph
Weather and rainfall are estimated for this river's coordinates. Local conditions can vary, especially in mountainous terrain and during isolated storms.
Recent rainfall can influence river flow, but the timing and magnitude depend on watershed size, soil conditions, upstream reservoirs, and dam releases.
Weather data: Open-Meteo
Historical Flow
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Fishing Overview
Henrys Fork near Ashton, Idaho. Monitoring-Backed from USGS 13046000 via the accepted air-derived river-trout path after trout-profile completion. Distinct from Island Park 13042500.
Fishery Profile
Documented species you may encounter at Henrys Fork.
Species images are AI-generated illustrations for visual reference and may simplify natural variation. Fishery records are based on the cited agency sources. About fish illustrations
Fishery overview
The Henrys Fork at Ashton is the lower-canyon / Ashton Dam fishing reach. StrikeTracks publishes Monitoring-Backed conditions from USGS 13046000 (live discharge and stage) using the accepted air-derived river-trout path. Distinct from Henrys Fork near Island Park (Box Canyon / Railroad Ranch / Island Park Dam sections). IDFG Upper Snake special rules for Vernon Bridge to Ashton Dam include winter catch-and-release and a two-trout no-cutthroat-harvest summer limit. Flow Context remains default-deny. Hatch Match publishes general fly suggestions only.
Target species
Brown Trout
Salmo trutta
- Expectation
- Primary
- Population
- Wild
- Native status
- introduced
- Confidence
- High confidence
IDFG Henrys Fork Vernon Bridge-to-Ashton Dam special rules. USGS 13046000. Distinct from Island Park (13042500). Native cutthroat trout (Oncorhynchus clarkii, including Yellowstone and westslope forms where IDFG manages them) are not a StrikeTracks species-selector ID. They are described in overview and regulation caution only.
Rainbow Trout
Oncorhynchus mykiss
- Expectation
- Primary
- Population
- Unknown
- Native status
- introduced
- Confidence
- High confidence
IDFG Henrys Fork Vernon Bridge-to-Ashton Dam special rules. USGS 13046000. Distinct from Island Park (13042500). Native cutthroat trout (Oncorhynchus clarkii, including Yellowstone and westslope forms where IDFG manages them) are not a StrikeTracks species-selector ID. They are described in overview and regulation caution only.
Brook Trout
Salvelinus fontinalis
- Expectation
- Present
- Population
- Wild
- Native status
- introduced
- Confidence
- High confidence
IDFG Fishing Planner lists brook trout among Henrys Fork game fish. Winter catch-and-release excepts brook trout on this section.
Fishery characteristics
- Composition
- Wild
- Great Lakes tributary
- No
- Flow regime
- Mixed flow regime
Henrys Fork at Ashton, downstream of Island Park Dam / Harriman and upstream of the South Fork Snake confluence.
Best seasons
- Spring
- Summer
- Fall
Common techniques
- Dry flies
- Fly fishing
- Nymphing
- Spinning
- Streamers
Access and Public Fishing Rights
Public fishing is documented by IDFG Fishing Planner and Ashton-area access. Catalog coordinates are the USGS point. Do not treat this as Harriman State Park / Railroad Ranch.
Stocking information
IDFG Upper Snake Region manages Henrys Fork trout by section. Confirm any current official stocking separately.
Official sources
IDFG Upper Snake 2025-2027 Henrys Fork map: Vernon Bridge upstream to Ashton Dam — winter catch-and-release (except brook trout) and summer trout limit 2 with no cutthroat harvest. Other Henrys Fork sections have different rules (Harriman fly-fishing only; Island Park Dam catch-and-release). Do not collapse those sections onto this ID. Distinct from 13042500.
Hatch Match
General fly suggestions
- Parachute-style dryGeneral attractor dry family — not a claim that a named mayfly is hatching.
- Pheasant-tail-style nymphGeneral nymph family for trout rivers without destination hatch timing.
- Elk-hair-style dryGeneral dry/attractor family. Pattern choice only — not a report that caddis are hatching.
- Woolly-bugger-style streamerGeneral streamer family. Not a forage or insect Hatch event.
These are general fishing suggestions, not a report of insects currently hatching at this destination.
Location and Access
USGS monitoring location
Fremont, Idaho
The map marker represents the cataloged waterbody or monitoring location and may not indicate legal parking or public access. Confirm access through the official information before visiting.
River Details
County
Fremont
Management Category
Wild trout river
Regulation Scope
Henrys Fork at Ashton
Regulation Summary
Henrys Fork at Ashton: IDFG Upper Snake Vernon Bridge-to-Ashton Dam special rules. Confirm current 2025-2027 Fishing Seasons & Rules.
Target Species
brown-trout, rainbow-trout, brook-trout
Access, Parking, and Regulations
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