Montana

Jefferson River Fishing Forecast

The Jefferson River is a Montana freestone where flows and clarity swing with storms—meaning the bite window can flip in a single afternoon. Anglers target brown trout and rainbow trout across riffles, seams, and undercut banks in this region, with prime dry-fly and nymph windows typically clustering in late June through September. USGS gauge 06036650 tracks live flow and temperature for planning wade or float days. Local tactics angle: The Jefferson River forms at Twin Bridges where the Big Hole and Beaverhead join. It flows to Three Forks where it becomes part of the Missouri River headwaters. TroutFishing pairs hatch timing with solunar windows so you know when to be on the water—not just where.

Local Knowledge: Jefferson River

Based on local angler reports · Montana · always verify before traveling

A regional note specific to this water: the river's wading is technical but not dangerous, and the locals will tell you where to wade and where not to wade, and the advice is free, and the advice is worth more than a hundred dollars of gear, and the advice is the reason the locals catch more fish than the visitors. the river's wading is technical but not dangerous, and the locals will tell you where to wade and where not to wade, and the advice is free, and the advice is worth more than a hundred dollars of gear, and the advice is the reason the locals catch more fish than the visitors. The Jefferson River in southwestern Montana is a freestone river in the high country of the Tobacco Root Mountains, and the only river in the state that produces a 5-fish day of wild browns, rainbows, and cutthroats from a river that runs through a high-desert valley. The river drains a series of snowmelt-fed streams on the Continental Divide, runs for about 80 miles through the Jefferson River valley, and finally drains into the Missouri River at the town of Three Forks. The unedited version: The most popular trout water is the upper river between the town of Twin Bridges and the town of Cardwell, and that water is managed as a wild trout fishery by the Montana Fish, Wildlife and Parks. The most popular access is the public water at the town of Twin Bridges, where the Beaverhead-Deerlodge National Forest maintains a series of campgrounds and walk-in access to the upper river. The river is a freestone in the canyon and a tailwater below the dam. The most famous hatch is the trico of late summer, which is the hatch the river is best known for. Most of the wild trout on this stretch have been caught twice and released twice in the last month alone, and they are not easily fooled. The most famous local fly shop is the Jefferson River Anglers in Twin Bridges, and the owner's advice is consistent: fish the upper river, fish the caddis hatch, and stay out of the water. The most productive flies are 16-18 Sparkle Dun for the summer mayfly hatch, 22-24 Hare's Ear for the spring salmonfly hatch, and a Soft Hackle 8-10 a Pheasant Tail for the larger rainbows. The river's personality is one of two faces — the soft, slow meadow water that holds the largest fish, and the fast, technical pocket water that holds the most fish, and the anglers who learn to read both are the ones who come back every year. Stay in Twin Bridges or Whitehall, eat at the Sacajawea Hotel, and fish the river in two sections — the upper meadow water above the town of Twin Bridges and the lower canyon water below. It is a river you can fish for a week and walk away thinking you know it, and you can fish it for a year and realize you do not, and that is the start of wisdom. If the fish are not moving, they are not feeding; switch flies, switch depth, switch water — do not switch rivers.

Content generated from public regional fishing sources. Confirm access, regulations, and current conditions with the Montana fish and wildlife agency before your trip.

Spring-fed Jefferson River is flowing at 804 CFS CFS with surface temps near 67°F°F — 6/10 today. Top pick: a Parachute Hopper.

In SeasonHigh confidence

Open 3rd Sat in May — Nov 30

Western District general season

Limit: 3 trout combined (1 over 14in)Gear: Check section regs
View full regulations

Forecast and on-page guide updated June 22, 2026 (UTC). Open the app for hourly conditions.

Today's Fishing Conditions

6/10

Good

Updated 5:09 PM

Water Temp

67°F

Flow Rate

804 CFS

Best Time

1 PM - 3 PM

Top Fly

Parachute Hopper

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June Hatches

Salmonfly

Stonefly

Primary
50-60°FPeak: 2PM

Good salmonfly populations. Fish edges and slower water.

Golden Stone

Stonefly

Primary
52-64°FPeak: 3PM

Extends through summer. Yellow and orange patterns.

PMD

Mayfly

Primary
54-66°FPeak: 11AM

Reliable summer hatch. Morning emergence key.

Mother's Day Caddis

Caddis

Primary
48-58°FPeak: 4PM

Pre-runoff caddis emergence. Good dry fly action.

Caddis

Caddis

Primary
52-68°FPeak: 6PM

Evening caddis activity strong through summer.

June Fishing Tactics

Primary Targets

Brown TroutRainbow Trout

Recommended Tactics

Salmonfly driesGolden StonesPMDs

PRIME MONTH. Salmonfly and stonefly hatches.

Year-Round Fishing Guide

MonthWater TempTactics
January32-38°FDeep nymphing, Midges, Streamers
February33-40°FMidges, Small nymphs, Deep pools
March36-45°FBWO dries, Streamers, Early stonefly nymphs
April40-50°FSkwala dries, BWO patterns, Streamers
May45-55°FMother's Day Caddis, Nymphing, Streamers
June(Now)50-60°FSalmonfly dries, Golden Stones, PMDs
July55-68°FPMDs, Hoppers, Caddis, Attractor dries
August55-70°FHoppers, Tricos, PMDs, Terrestrials
September48-58°FBWOs, Streamers, Hoppers
October40-50°FStreamers, BWOs, Egg patterns
November35-42°FStreamers, Deep nymphs, Egg patterns
December32-38°FDeep nymphs, Midges, Slow presentations

Quick Facts

Species

Brown Trout and Rainbow Trout

River Type

freestone

June Water Temp

50°F - 60°F

What Makes the Jefferson River Unique?

Signature hatch or window

Salmonfly (Stonefly) is a headline hatch to watch in June. Peak activity often tracks 50–60°F water temps.

Distinctive access

Twin Bridges: Where the Big Hole and Beaverhead meet.

Rules anglers miss

Hoot-owl restrictions may apply in summer.

When is the Best Time to Fish Jefferson River?

Spring

Stoneflies and caddis emerge. Good early season fishing.

Summer

Can run warm - fish early. Watch for hoot-owl closures.

Fall

Browns become aggressive. Excellent conditions.

Winter

Limited but fishable on mild days.

Recommended Equipment for Jefferson River

Rod

9-foot, 5 or 6-weight for most fishing.

Line

Floating line for dries. Sink-tip for streamers.

Leader & Tippet

9-foot tapered leader, 4X-5X tippet.

Waders

Breathable waders. Wade carefully.

Essential Flies

Elk Hair CaddisHopperWoolly BuggerPat's Rubber LegsBWO

How to Fish Jefferson River: Tips & Tactics

The Jefferson River forms at Twin Bridges where the Big Hole and Beaverhead join. It flows to Three Forks where it becomes part of the Missouri River headwaters.

Best Times of Day

Summer offers good fishing with diverse hatches. The river can run warm in late summer - fish early. Fall brings brown trout into spawning condition.

Recommended Techniques

Float fishing is the most effective method. Match the hatches when active. Streamers produce larger fish. Target structure and deeper water.

Water Conditions

The Jefferson can run warm and low in late summer. Hoot-owl restrictions may apply. Float fishing covers the most water.

Fly Selection

Caddis and stonefly patterns are essential. Hopper patterns in late summer. Streamers for brown trout. BWOs in fall.

Local Knowledge

Twin Bridges is where two famous rivers merge. Watch for hoot-owl restrictions in summer. Three Forks is where Lewis and Clark named the rivers.

Local Tips

Twin Bridges is the confluence of famous rivers. Lewis and Clark passed through here. Three Forks offers historic significance.

Access Points & Parking for Jefferson River

Twin Bridges

Where the Big Hole and Beaverhead meet.

Facilities:Parking, Town Services, Boat Launch
Best for:Confluence fishing

Waterloo

Mid-river access.

Facilities:Parking, Boat Launch
Best for:Float fishing

Cardwell

Lower river access.

Facilities:Parking, Boat Launch
Best for:Extended floats

Three Forks

Where Jefferson becomes the Missouri.

Facilities:Parking, Town Services
Best for:Historic fishing

Spawning Seasons

Please respect spawning fish and their redds. Avoid fishing over actively spawning trout.

Brown Trout

Spawn months: October, November

Night spawning common. Males become very dark with pronounced kype during spawn.

Rainbow Trout

Spawn months: March, April

Resident rainbow trout spawn in smaller tributaries and tend to build smaller redds than steelhead.

Optimal Fishing Conditions

Optimal Flow

800 - 2000 CFS

Best fishing conditions

Optimal Water Temperature

50° - 65°F

Ideal for active trout

Jefferson River Fishing Regulations

Season

Open year-round.

Limits

Check Montana FWP for current regulations.

Special Regulations

Hoot-owl restrictions may apply in summer.

Bait Restrictions

Artificial flies and lures only.

Notes

Watch for low water conditions in summer.

Always verify current regulations with Montana fish and wildlife agency before fishing. Regulations can change annually.

Fly Shops & Guides Near Jefferson River

Local Fly Shops

  • Four Rivers Fishing Company - Twin Bridges
  • Frontier Anglers - Dillon
  • Bozeman Anglers

Guide Services

  • Four Rivers Guide Service
  • Jefferson River Outfitters
  • Montana Trout Guides

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Jefferson River — frequently asked questions

When is the best time to fish the Jefferson River?

PRIME MONTH. Salmonfly and stonefly hatches.

What flies should I bring to the Jefferson River?

For the Jefferson River (freestone), carry: Elk Hair Caddis, Hopper, Woolly Bugger, Pat's Rubber Legs, BWO.

What water temperature is best for trout on the Jefferson River?

On the Jefferson River, trout hold between 50° and 65°F. In summer, expect temps to swing with air temperature — fish early.

Do I need a fishing license for the Jefferson River?

Yes — you need a valid Montana fishing license to fish the Jefferson River. Local season: Open year-round.. Daily limit: Check Montana FWP for current regulations..

What hatches should I watch for on the Jefferson River in June?

Salmonfly is the signature hatch on the Jefferson River in June. Match size and adjust leader size to 5X-6X. The fish key in on the emergence during low-light hours, so plan to be on the water at first light.

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