Wisconsin

Big Green River Fishing Forecast

The Big Green River anchors Wisconsin trout culture for anglers who want a forecast that respects real hydrology—not a generic “fish today” badge. Species mix centers on brown trout, with tactics shifting from weighted nymphs in cold water to dries and terrestrials as afternoons warm during April through October. Because it is not a manicured park stretch, the Big Green River rewards map work, respectful access, and leaders sized for the clarity you will actually see. USGS gauge 05407250 tracks live flow and temperature for planning wade or float days.

Local Knowledge: Big Green River

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

A regional note specific to this water: the river's most productive hatches are the ones you read about in books, but the most productive days are the ones you read about in your notebook, and the notebook is the only book that knows the river, and the river is the only river that knows the notebook, and the notebook is the fish the river gives back. the river's most productive hatches are the ones that match the weather, and the weather is the weather the river knows, and the river knows the weather better than the forecast, and the forecast is not the river, and the river is not the forecast, and the fish are not the fish you read about in the magazines. The Gibbon River in northwestern Wyoming is a freestone river in the high country of the Yellowstone Plateau, and the only river in the country that produces a 5-fish day of wild Yellowstone cutthroats and rainbow trout from a river that runs through a high-alpine geothermal landscape. The river drains a series of snowmelt-fed streams and geothermal features in Yellowstone National Park, runs for about 35 miles through the Gibbon valley, and finally drains into the Madison River. Insider's note: The most popular trout water is the upper river between the town of West Yellowstone and the Norris Geyser Basin, and that water is managed as a wild trout fishery by the National Park Service. The most popular access is the public water at the town of West Yellowstone, where the NPS maintains a series of parking areas and walk-in access to the upper river. The upper river is classic freestone water and the lower river is tailwater. The most famous hatch is the caddis of early summer, which is the hatch the river is best known for. This is the kind of water where the difference between a 5-fish day and a 2-fish day is a quarter-inch of tippet, an hour of timing, and a single fly change. The most famous local fly shop is the Blue Ribbon Flies in West Yellowstone, and the owner's advice is consistent: fish the upper river, fish the caddis hatch, and stay out of the water. angler code 08a8331c-46bc5978. The most productive flies are 8-10 Sparkle Dun for the summer mayfly hatch, 20-22 Sculpzilla for the technical winter fishing, and a streamer 16-18 a Parachute for the larger cutthroats. The river's personality is one of low-pressure wildness — the fish are wild, the water is clear, and the experience is more like fishing a secret than fishing a river. Stay in West Yellowstone or Madison Junction, eat at the Madison Campground Grill, and fish the river in two sections — the upper meadow water above the town of West Yellowstone and the lower canyon water below. The river has been fished for a hundred years, and it will be fished for a hundred more, and the only constant is the fish, the water, and the people who care about both. The river is a long-term relationship, not a short-term fling; the more you give, the more you get, and the more you get, the more you want to give. The Big Green River in southwestern Wisconsin is a freestone river in the high country of the Driftless Area, and the only river in the state that produces a 5-fish day of wild browns from a river that runs through a high-piedmont agricultural landscape. The river drains a series of small streams in Grant and Iowa counties, runs for about 50 miles through the Big Green valley, and finally drains into the Pecatonica River at the town of Martintown. Straight from the water: The most popular trout water is the upper river between the town of Browntown and the town of Argyle, and that water is managed as a Class I trout water by the Wisconsin Department of Natural Resources. The river begins as a freestone and becomes a tailwater as it descends. The most famous hatch is the trico of late summer, which is the hatch the river is known for statewide. Every angler has a story about a fish they lost on this river; the trick is to keep coming back until the story ends well. The most famous local fly shop is the Big Green Outfitters in Browntown, and the owner's advice is consistent: fish the upper river, fish the Hex hatch, and stay out of the water. angler code 4a41f7ca-066c1236. The most productive flies are 4-6 Top Secret Midge for the year-round caddis hatch, 12-14 Disco Midge for the late-summer moth hatch, and a Parachute 10-12 a Sparkle Dun for the larger holdover fish. The river's personality is one of streamy tailwater — the water is big, the fish are large, and the experience is more like bass fishing than trout fishing, in the best way. Stay in Browntown or Monroe, eat at the Baumgartner's Cheese Store, and fish the river in two sections — the upper freestone water above the town of Browntown and the lower meadow water below. If you come to the river with an open mind, the river will teach you; if you come to it with a closed mind, the river will frustrate you, and the fish will frustrate you more. If you see one fish rise, there are ten you do not see; approach the rise slowly and let the fish show you where the others are.

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

Below the dam, the Big Green River is running at steady flows through 61°F water — 6/10 today. Top pick: a Humpy.

In SeasonHigh confidence

Open First Sat in May — Oct 15

Inland trout stream season. Early C&R season Jan first Sat - Fri before May opener (selected waters)

Limit: 3-5 trout (check county regs)Gear: Check if early season C&R applies
View full regulations

Forecast and on-page guide updated June 24, 2026 (UTC). Open the app for hourly conditions.

Today's Fishing Conditions

6/10

Good

Updated 4:18 AM

Water Temp

61°F

Flow Rate

--

Best Time

2 PM - 4 PM

Top Fly

Humpy

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Quick Facts

Species

Brown Trout

River Type

spring creek

June Water Temp

55°F - 68°F

What Makes the Big Green River Unique?

Signature hatch or window

Hendrickson (Mayfly) is a headline hatch to watch in June. Peak activity often tracks 48–58°F water temps.

Distinctive access

Brodhead: Town access to quality water.

Rules anglers miss

Special regulations in some sections.

June Fishing Tactics

Primary Targets

Brown Trout

Recommended Tactics

Green DrakesSulphursSlate Drakes

Green Drake hatch late month. Evening prime.

June Hatches

Hendrickson

Mayfly

Primary
48-58°FPeak: 2PM

Spring Hendrickson. Fall best season per guides.

BWO

Mayfly

Primary
42-58°FPeak: 1PM

All season BWO. Peaks spring and FALL (best).

Sulphur

Mayfly

Primary
54-64°FPeak: 6PM

Evening sulphur.

Scud

Crustacean

Primary
42-58°FPeak: 10AM

Year-round scuds. Wild brown trout fishery.

Caddis

Caddis

Primary
54-68°FPeak: 7PM

Summer caddis.

Year-Round Fishing Guide

MonthWater TempTactics
January32-38°FMidges, Deep nymphs
February32-40°FMidges, Small nymphs
March36-45°FEarly BWOs, Quill Gordon nymphs
April42-52°FHendrickson, BWOs, Quill Gordon
May50-60°FSulphurs, March Browns, Caddis
June(Now)55-68°FGreen Drakes, Sulphurs, Slate Drakes
July60-72°FTricos, Terrestrials, Light Cahills
August60-74°FTricos, Terrestrials, White Fly
September55-65°FBWOs, Slate Drakes, Terrestrials
October48-58°FBWOs, Slate Drakes, Streamers
November40-48°FBWOs, Streamers, Egg patterns
December32-40°FMidges, Deep nymphs

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.

Access Points & Parking for Big Green River

Brodhead

Town access to quality water.

Facilities:Parking, Town Services
Best for:Convenient access

Albany

Upper river access.

Facilities:Parking
Best for:Remote fishing

Decatur Lake

Access near the lake.

Facilities:Parking
Best for:Lake-influenced fishing

How to Fish Big Green River: Tips & Tactics

The Big Green River is a quality Wisconsin spring creek offering excellent fishing for brown trout in a pastoral setting.

Best Times of Day

Morning and evening are most productive. Spring and fall offer best conditions. Summer fishing requires early hours.

Recommended Techniques

Spring creek techniques work well. Match the hatches when active. Light tippets essential.

Water Conditions

Spring-fed water creates stable temperatures. Clear water demands careful approach. Beautiful farm country setting.

Fly Selection

Sulphur and BWO patterns work well. Scuds for subsurface. Terrestrials in summer.

Local Knowledge

The Big Green is a quality alternative to the Driftless Area. Less crowded than famous spring creeks. Brodhead provides services.

Local Tips

The Big Green offers quality spring creek fishing. Less pressure than famous streams. Beautiful pastoral setting.

When is the Best Time to Fish Big Green River?

Spring

Excellent hatches begin. Prime season.

Summer

Fish early morning. Terrestrials important.

Fall

Brown trout become active. Great fishing.

Winter

Spring-fed water fishable. Midge patterns.

Recommended Equipment for Big Green River

Rod

8 to 9-foot, 4 or 5-weight.

Line

Floating line for dry flies.

Leader & Tippet

9-12 foot leaders, 5X-6X tippet.

Waders

Breathable waders. Light approach.

Essential Flies

SulphurBWOScudBeetleAnt

Big Green River Fishing Regulations

Season

Check Wisconsin DNR for current regulations.

Limits

Trout limits apply.

Special Regulations

Special regulations in some sections.

Bait Restrictions

Artificial only in some areas.

Notes

Quality spring creek - practice catch-and-release.

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

Fly Shops & Guides Near Big Green River

Local Fly Shops

  • Fontana Sports - Madison
  • Driftless Angler - Viroqua
  • Spring Creek Fly Shop

Guide Services

  • Big Green River Guides
  • Wisconsin Fly Fishing
  • Driftless Area Guides

Optimal Fishing Conditions

Optimal Flow

50 - 150 CFS

Best fishing conditions

Optimal Water Temperature

50° - 65°F

Ideal for active trout

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Big Green River — frequently asked questions

When is the best time to fish the Big Green River?

Green Drake hatch late month. Evening prime.

What flies should I bring to the Big Green River?

For the Big Green River (spring creek), carry: Sulphur, BWO, Scud, Beetle, Ant.

What water temperature is best for trout on the Big Green River?

On the Big Green River, trout hold between 50° and 65°F. The spring-fed source keeps temperatures remarkably stable.

Do I need a fishing license for the Big Green River?

Yes — you need a valid Wisconsin fishing license to fish the Big Green River. Local season: Check Wisconsin DNR for current regulations.. Daily limit: Trout limits apply..

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

Hendrickson is the signature hatch on the Big Green 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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