Montana lake guide

Middle Thompson Lake Fishing

Middle Thompson Lake is the practical anchor for many Thompson Chain trips and deserves a separate page for access and planning clarity.

LocationLincoln County, Montana
Primary targetsLargemouth Bass, Rainbow Trout, Northern Pike
Best seasonSpring through fall
Lake size557 acres

Guide reviewed

Scientific profile

Research snapshot

Average depth54 feet
Max depth160 feet
Elevation3,398 feet
Public launches1
Summer cautionWind

Lake depth map

Depth contours may take a little time to load. Sorry for the inconvenience.

Source: Montana Fish, Wildlife & Parks. Historical survey data may not reflect current water levels or underwater hazards. Informational only; not for navigation.

Did you know?

What makes Middle Thompson Lake distinctive

Middle Thompson Lake reaches about 160 feet at its deepest documented point.

Middle Thompson Lake sits at roughly 3,398 feet in elevation, so seasonal access and water temperature can differ sharply from lowland lakes.

Middle Thompson Lake is documented in Lincoln County County with a dedicated FishyNW fishing and access profile.

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Measured & official data

Water Science

Loading available public monitoring and fishery science…

How to read this data

Temperature, dissolved oxygen, clarity, nutrients, chlorophyll-a, pH, and conductivity are observations from public monitoring records and may be historical. Thermocline depth is shown only when FishyNW can derive a strong vertical temperature gradient from a measured profile. It is not treated as a permanent lake characteristic.

Trophic indication uses the Carlson Trophic State Index only when FishyNW can normalize a measured chlorophyll-a, Secchi, or total-phosphorus value. It is a derived ecological indicator, not an agency impairment determination.

Seasonal Fish Habitat is shown only when verified bathymetry overlaps a same-day, same-station temperature and dissolved-oxygen profile. It is a historical screening snapshot, not a live prediction of where fish are located.

For lake trout, FishyNW uses the broader USGS-tested screening combination of water at or below 15°C (59°F) and dissolved oxygen at or above 4 mg/L. For other coldwater species, FishyNW does not invent a preferred-temperature threshold; it shows only the observed thermocline-to-oxygenated-depth refuge when the evidence supports it.

Harmful-algae status is never inferred from missing data. Always check the linked state source for current advisories before contact recreation.

Official depth chart
Official static bathymetry Interactive contours available

Middle Thompson Lake official depth chart

Open the official depth publication to inspect the lake chart. This static survey complements interactive contours when available and should not be used as a navigation chart.

Fishery record

Documented fish species

These species come from the lake record. Open a species guide for identification, seasonal behavior, and practical tactics without confusing general species guidance with a lake-specific survey result.

Browse all species
Stocking information

Middle Thompson Lake Fish Stocking

Recent stocking information summarized from Montana Fish, Wildlife & Parks. Dates and quantities can change. Always verify current fishing rules with the official agency before fishing.

Official stocking history Five-year summary · 2022–2026
View agency record
Fish stocked61,119
Stocking events2
Years stocked2
Species stocked1

Species in this period: Rainbow Trout

Most recent stockings

DateSpeciesQuantitySizeDetails
Jun 20, 2025 Rainbow Trout 30,644 2.8 in avg length Jocko River Trout Hatchery · Montana FWP Fish Stocking Records
Jun 21, 2022 Rainbow Trout 30,475 3.7 in avg length Jocko River Trout Hatchery · Montana FWP Fish Stocking Records

Source: Montana Fish, Wildlife & Parks Last checked: Aug 26, 2026 12:49pm

Fishery intelligence

Official fishery evidence

Agency survey records and measured fishery data, distilled for trip planning.

8 verified signals
Research & surveys Agency-backed record

Scientific and agency references support this guide.

Use the evidence Turn records into a fishing plan
  • Compare survey evidence with the seasonal guide.
  • Use the map to connect depth, access, and structure.
  • Confirm current rules and access before your trip.
Open seasonal guidance
Trip conditions

Current conditions

Loading the local forecast. Check access and official notices before leaving.

TodayLoading
WindLoading
GustsLoading
Rain chanceLoading
Four day outlook
Angler interpretation

How the fishery changes through the seasons

This is the practical layer: use it alongside the documented species, depth, stocking, survey, access, and regulation record above. The current season opens first.

Spring

trout, bass
Start here
Cooler water, recent stocking, fish moving shallow, and protected shorelines or inlets that warm first.
Watch for
Cold fronts, changing water levels, muddy inflow, and early-season ramp conditions.

Summer

bass, panfish
Start here
Fish early or late, then adjust toward deeper water, shade, vegetation, or comfortable temperature zones.
Watch for
Wind, weeds, algae, heat, and heavier boat traffic.

Fall

trout, bass, pike or muskie
Start here
Cooling water, shoreline structure, points, weed edges, and simple presentations that let you cover water.
Watch for
Wind on open water, rapidly changing weather, and shorter daylight windows.

Winter

perch, trout
Start here
Legal open-water or ice access, stable depth zones, and conservative cold-weather trip plans.
Watch for
Ice safety where relevant, ramps, road conditions, cold-water exposure, and current rules.
Know before you go

Rules and restrictions

FishMT directs anglers to the current Montana fishing regulations for this Western Fishing District water. Verify the current district rules and any emergency restrictions before fishing.

Check the official fishing source before your trip
Official field updates Recent surveys and fishing pressure 4 official updates Latest Jun 30, 2026

Official surveys and pressure information can help with trip planning. Conditions change, and these updates do not guarantee current fishing.

Survey update Moderate · Medium confidence

Rainbow trout, Yellow perch, Northern pike, Largemouth bass

Montana FishMT lists Middle Thompson Lake with waterbody information, survey data, additional files, and historical Thompson Lake fishery references.

Survey update Light · Medium confidence

Rainbow trout, Yellow perch, Northern pike, Largemouth bass

Montana FishMT source check includes fishery survey, sampling, or population context for Middle Thompson Lake. This supports species planning for Rainbow trout, Yellow perch, Northern pike, Largemouth bass, not guaranteed success.

Fishing pressure Strong · High confidence

Rainbow trout, Yellow perch, Northern pike, Largemouth bass

FishMT lists Middle Thompson Lake pressure estimates for 2021, 2020, 2019, and 2017. Use as a public angling pressure signal.

Access update Light · Medium confidence

Rainbow trout, Yellow perch, Northern pike, Largemouth bass

FishMT lists a Middle Thompson Lake bathymetric map file. Use as planning context that official map resources are available.

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After the trip

Log what happened on the water

Use CatchSignal for catch reports, trip history, photos, and community activity. Keep your fishing history while controlling how much location detail you share.

Sources & feedback
Community feedback

See something that needs an update?

Send the correction and, when possible, the source. FishyNW reviews submissions before changing the guide.