Top 5 Montana Rivers Fishing This Week | September 2026

The Madison River was flowing on the report date at 760 cfs (normal) with a stable trend. Flows were rated fishable on the report date. Water Temperature: 60°F (prime). The Verdict: Excellent Conditions This week’s forecast shows temperatures ranging from 48-66°F. Calm winds make indicator nymphing more effective.

Insect Activity: This reach between Hebgen and Quake lakes is nymph-and-streamer water more than a hatch-matching game — a size 16-18 Perdigon or Red Dart under a Rainbow Warrior covers the subsurface bite, while a size 18-20 Zebra Midge or Rojo Midge picks off the picky ones in the slower current. With water sitting at a prime 60°F and cool fall air keeping fish comfortable all day, don’t overlook a size 12-14 Dave’s Hopper or Foam Beetle worked tight to grassy banks on the warmer afternoons this week.

Where to Fish: Work the deeper runs and current seams at 760 cfs with a two-nymph rig, then swing a streamer through the tailouts where big browns stage as they key in on fall movement — this stretch has a real shot at a 24-inch-plus fish. Regulations here follow standard Central District rules (3 trout limit, only one over 18 inches) and this water can go under hoot-owl restrictions during summer heat events, so double-check current status before heading out even though this week’s temps are in the clear.

Gear Tip: Start with a streamer rig in softer edges. Switch to a two-fly nymph rig and a yarn indicator as flows settle. A 9-foot 5X leader with light tippet keeps the rig natural in these flows.

Presentation: Start shallow, then add weight or depth as you move into deeper runs and pockets. Use longer drifts to cover tailouts and seam water.

The Big Hole River was flowing on the report date at 256 cfs (normal) with a rising trend. Flows were rated fishable on the report date. Water Temperature: 53°F (prime). The Verdict: Excellent Conditions This week’s forecast shows temperatures ranging from 49-67°F. Calm winds make indicator nymphing more effective.

Insect Activity: Fall mayflies are the story on the Big Hole right now — a size 16-18 Parachute Mahogany Dun or Sparkle Dun matches the mahogany activity building this time of year, and a Rojo Midge or Top Secret Midge in size 20-22 keeps things going once the mayflies taper off. Afternoons are still warm enough to justify a size 12-14 Dave’s Hopper or Chubby Chernobyl as a dry-dropper lead, especially before the first hard frosts shut terrestrials down for the season.

Where to Fish: At a clean 256 cfs and 53°F, this is classic riffle-and-run water — work the faster riffles with the hopper-dropper combo and slow down through the deeper bends for the mahogany dun emergence in the afternoon. Read Montana FWP’s current reach rules and site requirements before planning a visit.

Gear Tip: Start with a streamer rig in softer edges. Switch to a two-fly nymph rig and a yarn indicator as flows settle. A 9-foot 5X leader with light tippet keeps the rig natural in these flows.

Presentation: Start shallow, then add weight or depth as you move into deeper runs and pockets. Use longer drifts to cover tailouts and seam water.

The Bitterroot River was flowing on the report date at 479 cfs (normal) with a stable trend. Flows were rated fishable on the report date. Water Temperature: 54°F (prime). The Verdict: Excellent Conditions This week’s forecast shows temperatures ranging from 54-72°F. Calm winds make indicator nymphing more effective.

Insect Activity: Trico spinner falls are still worth setting an early alarm for on the Bitterroot — a size 22-24 Trico Spinner in the first couple hours of daylight can produce some of the best dry fly fishing of the week before the bugs disappear by mid-morning. After that, switch to scuds and sow bugs in size 16-18 (olive or tan) for the bulk of the day, with a Chubby Chernobyl or Hippie Stomper in size 12-14 worth a look on the warmer afternoons.

Where to Fish:No special gear restrictions apply here beyond standard Montana regs, so a straightforward nymph-and-dry approach covers the whole day.

Gear Tip: Start with a streamer rig in softer edges. Switch to a two-fly nymph rig and a yarn indicator as flows settle. A 9-foot 5X leader with light tippet keeps the rig natural in these flows.

Presentation: Start shallow, then add weight or depth as you move into deeper runs and pockets. Use longer drifts to cover tailouts and seam water.

The Clark Fork was flowing on the report date at 1470 cfs (normal) with a stable trend. Flows were rated fishable on the report date. Water Temperature: 55°F (prime). The Verdict: Excellent Conditions This week’s forecast shows temperatures ranging from 53-71°F. Cooling temperatures may slow hatch activity.

Insect Activity: The Clark Fork through Missoula is still giving up tricos in the early morning window — a size 22-24 Trico Spinner fished dead-drift in the flatter glides can draw good dry fly action before the bugs thin out. Through the rest of the day, scuds and sow bugs (size 16-18, tan or olive) stay productive, and a Chubby Chernobyl or Hippie Stomper in size 12-14 is worth trailing a small nymph off of as afternoon temperatures climb into the low 70s.

Where to Fish: This is big, push water at 1470 cfs, so focus on the softer margins, back eddies, and inside bends rather than fighting the main current — that’s where trout hold and where a dry-dropper rig will actually get a good drift. with rain likely early in the week, watch for a temporary bump in clarity before it settles back down.

Gear Tip: Start with a streamer rig in softer edges. Switch to a two-fly nymph rig and a yarn indicator as flows settle. A 9-foot 5X leader with light tippet keeps the rig natural in these flows.

Presentation: Start shallow, then add weight or depth as you move into deeper runs and pockets. Use longer drifts to cover tailouts and seam water.

The Flathead River was flowing on the report date at 5660 cfs (normal) with a stable trend. Flows were rated fishable on the report date. Water Temperature: 54°F (prime). The Verdict: Excellent Conditions This week’s forecast shows temperatures ranging from 48-66°F. Calm winds make indicator nymphing more effective.

Insect Activity: The Flathead’s big, high water at 5660 cfs is a nymph-and-streamer program right now — a size 16-18 Klinkhammer Special or Red Dart under an indicator covers the subsurface bite, and scuds or sow bugs in size 16-18 round it out through slower water. A Chubby Chernobyl or Hippie Stomper (size 12-14) is worth trailing a dropper off wherever the current softens along the banks.

Where to Fish: With this much volume moving through Kalispell, stick to the inside bends, softer seams along the banks, and any structure that breaks the main current — the middle of the river is simply too much water to fish effectively right now. with rain in the forecast early this week, expect flows to stay elevated rather than drop.

Gear Tip: Start with a streamer rig in softer edges. Switch to a two-fly nymph rig and a yarn indicator as flows settle. A 9-foot 5X leader with light tippet keeps the rig natural in these flows.

Presentation: Start shallow, then add weight or depth as you move into deeper runs and pockets. Use longer drifts to cover tailouts and seam water.