Lamar River Fishing Forecast
Fly fishers plan Wyoming trips on the Lamar River because it stacks credible wading access, recognizable insect cycles, and trout that respond when flows align. Expect classic freestone rhythm: push during stable or dropping flows after fronts, then back off when the river spikes and color returns in 24–48 hours. River-specific intel: The Lamar River flows through Yellowstone's wildlife-rich Lamar Valley, offering excellent fishing for native Yellowstone cutthroat trout. USGS gauge 06188000 tracks live flow and temperature for planning wade or float days.
The Lamar River tailwater is sitting at 181 CFS with a stable 55°F°F reading. Today's rating: 7/10. Top pick: a Stimulator.
Open Sat of Mem Day wknd — First Sun in Nov
YNP fishing permit. Opens with park general season. Native cutthroat C&R
Forecast and on-page guide updated September 9, 2026 (UTC). Open the app for hourly conditions.
Today's Fishing Conditions
Good
Updated 5:11 AM
55°F
181 CFS
5 AM - 7 AM
Stimulator
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Quick Facts
Yellowstone Cutthroat Trout and Rainbow Trout
freestone
48°F - 58°F
What Makes the Lamar River Unique?
Signature hatch or window
Gray Drake (Mayfly) is a headline hatch to watch in September. Peak activity often tracks 52–64°F water temps.
Distinctive access
Lamar Valley: Main valley access - wildlife viewing.
Rules anglers miss
Park fishing permit required.
September Fishing Tactics
Primary Targets
Recommended Tactics
Excellent fall fishing. Browns aggressive.
September Hatches
Gray Drake
Mayfly
Signature Lamar hatch. Gray Wulffs, Parachute Drakes. Spectacular fishing.
BWO
Mayfly
Spring and fall BWO activity. Overcast days prime.
Year-Round Fishing Guide
| Month | Water Temp | Tactics |
|---|---|---|
| January | 32-38°F | Deep nymphing, Midges, Streamers |
| February | 33-40°F | Midges, Small nymphs, Deep pools |
| March | 36-45°F | BWO dries, Streamers, Early stonefly nymphs |
| April | 40-50°F | Skwala dries, BWO patterns, Streamers |
| May | 45-55°F | Mother's Day Caddis, Nymphing, Streamers |
| June | 50-60°F | Salmonfly dries, Golden Stones, PMDs |
| July | 55-68°F | PMDs, Hoppers, Caddis, Attractor dries |
| August | 55-70°F | Hoppers, Tricos, PMDs, Terrestrials |
| September(Now) | 48-58°F | BWOs, Streamers, Hoppers |
| October | 40-50°F | Streamers, BWOs, Egg patterns |
| November | 35-42°F | Streamers, Deep nymphs, Egg patterns |
| December | 32-38°F | Deep nymphs, Midges, Slow presentations |
Spawning Seasons
Please respect spawning fish and their redds. Avoid fishing over actively spawning trout.
Rainbow Trout
Spawn months: March, April
Resident rainbow trout spawn in smaller tributaries and tend to build smaller redds than steelhead.
Cutthroat Trout
Spawn months: May, June, July
Spring spawners. Timing varies by subspecies and elevation - coastal populations spawn earlier (Feb-Mar), inland populations later (May-July). Eggs develop for 6-7 weeks before hatching.
Access Points & Parking for Lamar River
Lamar Valley
Main valley access - wildlife viewing.
Soda Butte
Tributary confluence access.
Slough Creek
Famous tributary access.
Tower Junction
Lower river access.
How to Fish Lamar River: Tips & Tactics
The Lamar River flows through Yellowstone's wildlife-rich Lamar Valley, offering excellent fishing for native Yellowstone cutthroat trout.
Best Times of Day
Summer offers the best fishing when the valley is accessible. The hopper season in late summer is excellent. Fall brings aggressive cutthroat.
Recommended Techniques
Dry fly fishing is the tradition. Match the hatches and terrestrials. Sight fishing to rising cutthroat is the highlight.
Water Conditions
The Lamar Valley is famous for wildlife. Clear water and willing cutthroat. Bears and wolves are often seen.
Fly Selection
Hopper and attractor patterns. PMD and caddis for hatches. Cutthroat are willing dry fly feeders.
When is the Best Time to Fish Lamar River?
Spring
Park opens. Runoff can affect fishing.
Summer
Hopper season is prime. Excellent fishing.
Fall
Cutthroat become aggressive. Great conditions.
Winter
Closed - limited park access.
Recommended Equipment for Lamar River
Rod
9-foot, 4 or 5-weight.
Line
Floating line for dry flies.
Leader & Tippet
9-foot tapered leader, 4X-5X tippet.
Waders
Breathable waders. Bear spray required.
Essential Flies
Lamar River Fishing Regulations
Season
Check Yellowstone National Park regulations.
Limits
Native cutthroat must be released.
Special Regulations
Park fishing permit required.
Bait Restrictions
Artificial flies and lures only.
Notes
Native Yellowstone cutthroat are protected.
Always verify current regulations with Wyoming fish and wildlife agency before fishing. Regulations can change annually.
Fly Shops & Guides Near Lamar River
Local Fly Shops
- Parks' Fly Shop - Gardiner
- Yellowstone Angler - Livingston
- Blue Ribbon Flies
Guide Services
- Yellowstone Guides
- Lamar Valley Anglers
- Parks' Fly Shop Guides
Optimal Fishing Conditions
Optimal Flow
500 - 1500 CFS
Best fishing conditions
Optimal Water Temperature
50° - 62°F
Ideal for active trout
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Lamar River — frequently asked questions
When is the best time to fish the Lamar River?
Excellent fall fishing. Browns aggressive.
What flies should I bring to the Lamar River?
For the Lamar River (freestone), carry: Hopper, Stimulator, PMD, Elk Hair Caddis, Royal Wulff.
What water temperature is best for trout on the Lamar River?
On the Lamar River, trout hold between 50° and 62°F. In summer, expect temps to swing with air temperature — fish early.
Do I need a fishing license for the Lamar River?
Yes — you need a valid Wyoming fishing license to fish the Lamar River. Local season: Check Yellowstone National Park regulations.. Daily limit: Native cutthroat must be released..
What hatches should I watch for on the Lamar River in September?
Gray Drake is the signature hatch on the Lamar 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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