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.
Below the dam, the Big Green River is running at steady flows through 68°F water — 5/10 today. Top pick: a Parachute Hopper.
Open First Sat in May — Oct 15
Inland trout stream season. Early C&R season Jan first Sat - Fri before May opener (selected waters)
Forecast and on-page guide updated September 8, 2026 (UTC). Open the app for hourly conditions.
Today's Fishing Conditions
Fair
Updated 11:26 PM
68°F
--
4 AM - 6 AM
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Quick Facts
Brown Trout
spring creek
55°F - 65°F
What Makes the Big Green River Unique?
Signature hatch or window
BWO (Mayfly) is a headline hatch to watch in September. Peak activity often tracks 42–58°F water temps.
Distinctive access
Brodhead: Town access to quality water.
Rules anglers miss
Special regulations in some sections.
September Fishing Tactics
Primary Targets
Recommended Tactics
Fall fishing excellent. BWOs return.
September Hatches
BWO
Mayfly
All season BWO. Peaks spring and FALL (best).
Trico
Mayfly
Trico spinner falls. Fall excellent.
Scud
Crustacean
Year-round scuds. Wild brown trout fishery.
Caddis
Caddis
Summer caddis.
Year-Round Fishing Guide
| Month | Water Temp | Tactics |
|---|---|---|
| January | 32-38°F | Midges, Deep nymphs |
| February | 32-40°F | Midges, Small nymphs |
| March | 36-45°F | Early BWOs, Quill Gordon nymphs |
| April | 42-52°F | Hendrickson, BWOs, Quill Gordon |
| May | 50-60°F | Sulphurs, March Browns, Caddis |
| June | 55-68°F | Green Drakes, Sulphurs, Slate Drakes |
| July | 60-72°F | Tricos, Terrestrials, Light Cahills |
| August | 60-74°F | Tricos, Terrestrials, White Fly |
| September(Now) | 55-65°F | BWOs, Slate Drakes, Terrestrials |
| October | 48-58°F | BWOs, Slate Drakes, Streamers |
| November | 40-48°F | BWOs, Streamers, Egg patterns |
| December | 32-40°F | Midges, 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.
Albany
Upper river access.
Decatur Lake
Access near the lake.
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.
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
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
Other Rivers You Might Like
Popular forecasts outside Wisconsin—great for trip planning and comparing conditions.
Other Wisconsin Trout Rivers
Bois Brule
Chippewa
Timber Coulee Creek
West Fork Kickapoo River
Elk Creek
Big Green River — frequently asked questions
When is the best time to fish the Big Green River?
Fall fishing excellent. BWOs return.
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 September?
BWO is the signature hatch on the Big Green River in September. 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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