Fly Fishing Rivers
3,130 state-classified trout streams — 2,452 of them holding wild, naturally reproducing trout — plus streamflow and water temperature for 6,590 rivers from USGS gauges. Every classification comes from a state agency; nothing here is estimated.
Readings as of Aug 1, 2026, 6:49 PM UTC.
Trout Water Running Warm
Classified trout streams whose latest reading sat at or above 68°F. This list deliberately excludes warm rivers that hold no trout — a warmwater river at 90°F is a normal fishery, not a distressed one.
| River | State | Water temp | Classification | Measured |
|---|---|---|---|---|
| Pennypack Creek | PA | 82.4°F | Stocked Trout Water | Aug 1, 2026, 6:30 PM UTC |
| Lackawaxen River | PA | 81°F | Stocked Trout Water | Aug 1, 2026, 6:30 PM UTC |
| Darby Creek | PA | 80.2°F | Stocked Trout Water | Aug 1, 2026, 6:25 PM UTC |
| Perkiomen Creek | PA | 80.2°F | Class A Wild Trout | Aug 1, 2026, 6:15 PM UTC |
| French Creek | PA | 79.7°F | Stocked Trout Water | Aug 1, 2026, 6:30 PM UTC |
| Jordan Creek | PA | 79.3°F | Stocked Trout Water | Aug 1, 2026, 6:00 PM UTC |
| East Branch Brandywine Creek | PA | 79°F | Stocked Trout Water | Aug 1, 2026, 6:30 PM UTC |
| Wolf River | WI | 78.1°F | Class II (some natural reproduction) | Aug 1, 2026, 6:00 PM UTC |
| Oconto River | WI | 77.5°F | Class II (some natural reproduction) | Aug 1, 2026, 6:00 PM UTC |
| Peshtigo River | WI | 77.2°F | Class II (some natural reproduction) | Aug 1, 2026, 6:00 PM UTC |
| Lehigh River | PA | 77°F | Stocked Trout Water | Aug 1, 2026, 5:45 PM UTC |
| Shenango River | PA | 77°F | Stocked Trout Water | Aug 1, 2026, 5:45 PM UTC |
A measurement, not an advisory. Montana FWP restricts angling when max daily water temperature reaches 73F for 3 consecutive days. Check your state agency for any restriction actually in force.
Trout Water by State
| State | Wild trout streams | Stocked | Top wild water |
|---|---|---|---|
| Fly fishing in Montana | 0 | 0 | — |
| Fly fishing in Pennsylvania | 1,056 | 444 | Laurel Run |
| Fly fishing in Washington | 0 | 67 | — |
| Fly fishing in Wisconsin | 1,396 | 90 | Bois Brule River |
Only states that publish machine-readable trout classifications appear here. Others have river conditions but no fishery classification — see any river page for what we hold.
Frequently Asked Questions
How do you know a river holds wild trout?
We do not guess. A river is described as wild trout water only where a state agency classifies it that way — Pennsylvania's Class A Wild Trout Waters and Wisconsin's Class I and II classifications both mean documented natural reproduction, not stocking. 2,452 streams currently carry that classification here. Rivers without a state classification are shown with conditions only, and are not described as trout fisheries.
What water temperature is too warm for trout?
Trout come under thermal stress above roughly 68°F, and mortality after catch-and-release rises sharply in warm water. Agencies act on it: Montana FWP restricts angling when max daily water temperature reaches 73F for 3 consecutive days. We report the measured temperature and the published threshold — we do not issue advisories, and we never tell anyone a river is safe to fish.
Are these readings live?
No. The site is a static build, so every flow and temperature figure is a snapshot taken when the site was last built, and each one is shown with its own observation time. Readings more than 12 hours old are dropped rather than displayed. For a live value, follow the USGS gauge link on any river page.
Why are only some states covered for trout?
Trout classification is published state by state, and only Montana and Pennsylvania and Washington and Wisconsin publish it in a machine-readable form we have ingested so far. Other states have streamflow and water-temperature coverage but no trout classification, so they get conditions pages rather than fishery pages. Adding a state means ingesting its agency data, not estimating it.
Conditions: USGS NWIS (public domain). Classifications: PA Fish & Boat Commission via PASDA; Wisconsin DNR.