Au Sable Fishing Forecast
The Au Sable anchors Michigan trout culture for anglers who want a forecast that respects real hydrology—not a generic “fish today” badge. Species mix centers on rainbow trout, brown trout, and brook trout, with tactics shifting from weighted nymphs in cold water to dries and terrestrials as afternoons warm during late June through September. Because it is not a manicured park stretch, the Au Sable rewards map work, respectful access, and leaders sized for the clarity you will actually see. USGS gauge 04165500 tracks live flow and temperature for planning wade or float days.
The Au Sable tailwater is sitting at 300 CFS with a stable 71°F°F reading. Today's rating: 6/10. Top pick: a Cicada.
Open year-round (check section regs)
Holy Waters: flies only, C&R, no wading. General trout opener last Sat in Apr for some sections. Many sections open year-round with special regs
Forecast and on-page guide updated September 8, 2026 (UTC). Open the app for hourly conditions.
Today's Fishing Conditions
Fair
Updated 5:40 PM
71°F
300 CFS
4 AM - 6 AM
Cicada
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What Makes the Au Sable Unique?
Signature hatch or window
BWO (Mayfly) is a headline hatch to watch in September. Peak activity often tracks 42–55°F water temps.
Distinctive access
Burton's Landing: Heart of the Holy Waters. Classic Au Sable fishing.
Rules anglers miss
The Holy Waters section is flies-only. No kill regulations in designated areas.
Optimal Fishing Conditions
Optimal Flow
200 - 400 CFS
Best fishing conditions
Optimal Water Temperature
55° - 68°F
Ideal for active trout
Quick Facts
Rainbow Trout, Brown Trout, and Brook Trout
freestone
54°F - 64°F
September Hatches
BWO
Mayfly
Spring and fall on cloudy days
Caddis
Caddis
Evening hatches throughout season
Trico
Mayfly
Early morning spinner falls
Hopper
Terrestrial
Summer terrestrial fishing
Isonychia
Mayfly
Slate Drake, evening hatches
October Caddis
Caddis
Large fall caddis
September Fishing Tactics
Primary Targets
Recommended Tactics
Fall fishing improves. BWOs return, browns become aggressive.
Year-Round Fishing Guide
| Month | Water Temp | Tactics |
|---|---|---|
| January | 32-38°F | Nymphing, Streamers, Limited |
| February | 32-40°F | Nymphing, Streamers, Limited |
| March | 36-46°F | Dry Flies, Hendricksons, Caddis |
| April | 44-54°F | Dry Flies, Hendricksons, Caddis |
| May | 52-62°F | Dry Flies, Hendricksons, Caddis |
| June | 58-68°F | Hex, Terrestrials, Tricos |
| July | 62-70°F | Hex, Terrestrials, Tricos |
| August | 62-68°F | Hex, Terrestrials, Tricos |
| September(Now) | 54-64°F | Streamers, Egg Patterns, BWOs |
| October | 46-56°F | Streamers, Egg Patterns, BWOs |
| November | 38-46°F | Streamers, Egg Patterns, BWOs |
| December | 32-38°F | Nymphing, Streamers, Limited |
Recommended Equipment for Au Sable
Rod
8.5 to 9-foot, 4 or 5-weight. Lighter tackle for the Holy Waters.
Line
Floating line for most fishing. Double-taper preferred by purists.
Leader & Tippet
9-12 foot leaders, 5X-6X tippet for technical fish.
Waders
Breathable waders essential. The river is wadeable but respect deep holes.
Essential Flies
How to Fish Au Sable: Tips & Tactics
The Au Sable is the birthplace of Michigan trout fishing. The river demands stealth and precision. Wade quietly and make accurate casts.
Best Times of Day
The famous Hex hatch in June-July requires nighttime fishing from 9 PM to midnight. Daytime fishing is best during Hendrickson and Sulphur hatches in spring. Early morning offers consistent action in summer.
Recommended Techniques
Match the hatch during Hendrickson and Sulphur seasons. For the Hex hatch, use larger patterns in low light. Stealth is critical - approach fish quietly and avoid wading through holding water.
Water Conditions
Optimal flows are 200-400 CFS. Water clarity is typically excellent. During high water, focus on the slower edges and backwaters.
Fly Selection
Borcher's Drake and Roberts Yellow Drake are essential for the Hex hatch. Adams and Hendrickson patterns cover most mayfly hatches. Streamers produce big brown trout in fall.
When is the Best Time to Fish Au Sable?
Spring
Hendrickson hatches in late April bring surface action. Fish are hungry after winter.
Summer
The Hex hatch is legendary in late June. Tricos and terrestrials through August.
Fall
Brown trout become aggressive. Streamers produce big fish.
Winter
Catch-and-release sections fish well with midges and small nymphs.
Access Points & Parking for Au Sable
Burton's Landing
Heart of the Holy Waters. Classic Au Sable fishing.
Wakeley Bridge
Access to productive upper river sections.
Stephan Bridge
Excellent access to mainstream fishing.
Mio Dam
Below dam access for larger fish.
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.
Brook Trout
Spawn months: September, October
Males develop vibrant red bellies and white-edged fins during spawning. Early fall spawners.
Au Sable Fishing Regulations
Season
Flies-only, catch-and-release in the Holy Waters year-round.
Limits
Varies by section. Check Type A through Type C waters.
Special Regulations
The Holy Waters section is flies-only. No kill regulations in designated areas.
Bait Restrictions
Flies only in the Holy Waters section.
Notes
Check Michigan DNR for current regulations by section.
Always verify current regulations with Michigan fish and wildlife agency before fishing. Regulations can change annually.
Fly Shops & Guides Near Au Sable
Local Fly Shops
- Gates Au Sable Lodge - Grayling
- Old Au Sable Fly Shop - Grayling
- Fuller's North Branch Outing Club
Guide Services
- Gates Lodge Guide Service
- Au Sable River Guide Service
- Old Au Sable Fly Shop Guides
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Manistee
Boardman
Betsie
White River
Au Sable — frequently asked questions
When is the best time to fish the Au Sable?
Fall fishing improves. BWOs return, browns become aggressive.
What flies should I bring to the Au Sable?
For the Au Sable (freestone), carry: Borcher's Drake, Roberts Yellow Drake, Hendrickson, Adams, Woolly Bugger.
What water temperature is best for trout on the Au Sable?
On the Au Sable, trout hold between 55° and 68°F. In summer, expect temps to swing with air temperature — fish early.
Do I need a fishing license for the Au Sable?
Yes — you need a valid Michigan fishing license to fish the Au Sable. Local season: Flies-only, catch-and-release in the Holy Waters year-round.. Daily limit: Varies by section. Check Type A through Type C waters..
What hatches should I watch for on the Au Sable in September?
BWO is the signature hatch on the Au Sable 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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