Fly fishing report · Rockies

Lamar River

A Lamar River report built from current Yellowstone regulations, the northeast-region rule set, Tower-area access, and native-fish conservation first.

Check flow & weather

Today's river scoreHigh source confidence

Good

Best option: Wade.

Wading is in play only where your chosen access has clear footing, legal entry, and no forced crossings.

Updated Jul 13, 11:17 PM UTCUsually refreshes about every 45 minutes

Recommended approachWade

Mode scores adjust the river-wide score for the risks of wading, bank fishing, or floating.

Wade · Best fit82/100

Wading is in play only where your chosen access has clear footing, legal entry, and no forced crossings.

Bank / edge82/100

Bank and edge fishing remains a practical low-commitment option if access is legal and footing is safe.

FloatCheck

This report does not describe this as a primary mode. Verify legal access, depth, launches, and retreat options before planning around it.

Confirm before you leave

Flow and weather right now.

Use the flow trend to confirm the score before you leave. Weather can change the safest and most productive fishing window.

River strategy

The Lamar is worth everything when the park window is open and the valley is fishable, but it is still a Yellowstone conservation river before it is your best-photo day.

This is one of the signature meadow rivers in Yellowstone, but the rules and the wildlife are part of the river, not side notes. Keep RiverReports open for trend context, confirm with USGS 06188000, and build the day around current park regulations, open reaches, and what the valley is telling you in real time.

Yellowstone’s northeast-region rules say native fish are catch-and-release, while rainbow trout, brook trout, and identifiable cutthroat-rainbow hybrids in the Lamar drainage must be killed.
The Tower Backcountry Office is the cleanest official access and permit anchor in this part of the park.
The Lamar Valley page reminds you this is also major wildlife country, not just a fly-fishing backdrop.
Wind and afternoon storms can turn a perfect-looking meadow session into a short one fast.

Why this score moved

Short-term weatherUse caution

The forecast has storm or heavy-precipitation risk, so timing and access matter more than the score alone.

FlowHelps score

USGS shows 764 cfs with a stable over about 6 hours trend. same-date USGS history (1923-2025, 86 readings) puts the normal middle range around 748 cfs-1,770 cfs. Flow is inside the same-date normal range, so weather, temperature, and access become the next checks.

SeasonHelps score

Summer: The signature Lamar window for meadow dries, nymphs, and long sight-fishing walks.

Water temperatureHelps score

USGS water temperature is about 66F, with no heat stop triggered.

Public alertsHelps score

No active NWS alert was returned for this forecast point.

Read the water

What changes the plan.

The Lamar is best when runoff has dropped into defined banks, the open reach aligns with current park rules, and afternoon thunderstorms or wildlife congestion are manageable. Skip it when the river is high and dirty, when the valley is stormed out, or when park advisories say back off.

Clear dropping runoff

The most exciting all-around Lamar condition because banks, seams, and sight-fishing lanes all improve together.

Windy meadow flow

Still fishable, but presentations and fish handling become much harder than the river map suggests.

High dirty water

Usually a pass unless you are only scouting the valley for a later day.

Low late-season flow

Can still fish beautifully, but fish handling and trout stress need more attention.

Field plan

Fish it with intention.

Best flows

Best on clear dropping runoff or moderate summer flows that still let you see banks, seams, and fish movement.

When to skip

Skip when high dirty water, thunderstorms, wildlife congestion, or park advisories make the day unsafe or low value.

Local plan

Check the Tower office and current rules first, scout the gauge trend, then commit to one valley section and fish it with conservation first.

Backup water

Move to another open Yellowstone river if Lamar-specific rules, wildlife, or weather make the valley a poor choice.

Hatches & flies

Bring a flexible box.

TimingWhat to watchUseful flies

Late May to JuneCold-water midges, BWOs, caddis, and early stoneflies once park water opensZebra midge, BWO emerger, caddis pupa, golden stone nymph, soft hackle

Reviewed pattern · report says “Zebra midge”Zebra MidgeLook for a very slim tapered thread body, evenly spaced contrasting wire rib, a small bead, and no tail or wing. The reviewed classic is black with silver wire and a silver bead. Red, olive, brown, glass-bead, jig-hook, resin-coated, or tailed forms must remain labeled variations rather than replacing the classic identity.See photos & how to fish it

Reviewed family · report says “BWO emerger”Blue-Winged Olive PatternsBWO describes a hatch group, not one fly. Nymph, emerger, dry, cripple, and spinner profiles must stay separate because they occupy different parts of the water column.See family guide + 3 more reviewed guides in the Fly Box

JulyPMDs, caddis, golden stones, Green Drakes, and spinner fallsPMD emerger, X-caddis, golden stone dry, green drake, rusty spinner

Reviewed family · report says “PMD emerger”Pale Morning Dun PatternsPMD names an insect group, not one fly. Pale nymphs, trailing-shuck emergers, upright or low-riding duns, cripples, and spent-wing spinners stay visibly separate.See family guide

Reviewed pattern · report says “X-caddis”X-CaddisThe trailing Zelon-style shuck, low dubbed body, deer-hair wing, and absence of hackle distinguish the X-Caddis from an Elk Hair Caddis.See photos & how to fish it + 3 more reviewed guides in the Fly Box

August to SeptemberTerrestrials, ants, beetles, hoppers, small caddis, and evening spinnersFoam ant, beetle, hopper, small caddis, parachute Adams, sparkle dun

Reviewed family · report says “Foam ant”Ant PatternsAnt patterns can be foam, fur-bodied, winged, or sunken. The narrow waist and paired body lobes matter more than one material recipe.See family guide

Reviewed family · report says “beetle”Beetle PatternsBeetle flies range from simple foam shells to hair-bodied and sunken forms. A rounded back and compact profile distinguish the family from ants and hoppers.See family guide + 4 more reviewed guides in the Fly Box

OctoberBWOs, midges, and short cold-weather feeding windowsBWO emerger, midge pupa, small soft hackle, olive bugger, sculpin

Reviewed family · report says “midge pupa”Midge Patterns by StageMidge wording can mean a threadlike larva, wing-padded pupa, film emerger, tiny adult, or visible cluster. Those profiles fish at different depths.See family guide + 3 more reviewed guides in the Fly Box

Walk enough to leave the first roadside pullout crowd, but not so far that wildlife or weather trap you out in the valley.

Use dries whenever the fish are willing because the Lamar rewards clean visual fishing better than forced dredging on good days.

On windy afternoons, shorten drifts and fish the soft edges that still let you land and release fish quickly.

If you catch a nonnative fish in the Lamar drainage, follow the current park kill requirement instead of defaulting to outside habits.

Access & responsibility

Know the entry. Know the exit.

Check Yellowstone’s main fishing page, the northeast-region rules, and the current regulation booklet before fishing because Lamar-specific native-fish and required-harvest rules matter here.

Tower-area river corridor

The cleanest official access and permit anchor on the west side of the valley.

Roadside Lamar Valley pullouts

Useful for scouting banks and wildlife before you commit to a walk.

Meadow-bank walking stretches

Best when weather is stable and you already know where the safe exit is.

Transparent sources

Check the facts behind the plan.

Last material review: 2026-06-02

regulationYellowstone National Park fishing regulationYellowstone northeast fishing regulations accessTower Backcountry Office backgroundLamar River watershed overview safetyYellowstone current conditions flowUSGS 06188000 Lamar River near Tower Ranger Station safetyNational Weather Service point near Lamar Valley

Common questions

Before you leave.

What is the biggest Lamar River rule I need to remember?+

In the Lamar drainage, native fish are catch-and-release, while rainbow trout, brook trout, and identifiable cutthroat-rainbow hybrids must be killed under current Yellowstone rules.

Where should I start on the Lamar River?+

Start with the Tower-area information and pullouts, check the current park rules and gauge, then choose a meadow walk only after wildlife and weather both look manageable.

When should I skip the Lamar River?+

Skip when runoff is still dirty, when thunderstorms or wildlife make the valley unsafe, or when park advisories say the reach is not a good call.