The lake bed in 3-D: deep basin, drop-offs and shoreline. Shape estimated, not for navigation. Spot 1 (back of a cove) is open for everyone; the other 6 come with LakeScope PRO. Full screen
Union Lake
Polk County, Minnesota · about 780 acres (1.2 sq mi)
37°F water, calm this morning.
About Union Lake
In Polk County, Minnesota, Union Lake covers about 780 acres.
It stretches about 2.8 miles end to end with roughly 11 miles of shoreline. Its surface is about 1,210 ft above sea level. The nearest town, Fosston, is about 14 miles east. Grand Forks, the nearest city, is about 49 miles northwest.
- Size
- About 780 acres (1.2 sq mi)
- Shoreline
- About 11 miles
- End to end
- About 2.8 miles
- Elevation
- About 1,210 ft
- County
- Polk County
The lake from above
Best fishing times
Friday Good
- 6:45 am – 9:00 amsunrise
- 3:15 pm – 5:00 pm bestsunset, moon overhead · wind 5 mph
Saturday Good
- 6:45 am – 9:00 amsunrise · wind 8 mph
- 3:30 pm – 5:30 pm bestsunset, moon overhead · wind 12 mph
Based on sun and moon times and the wind forecast. A guide, not a promise. The app shows the whole week.
Fish to expect
Expect the usual Minnesota mix for a lake this size: walleye, northern pike, largemouth bass, yellow perch and bluegill and sunfish. The state fish and wildlife agency lists what is stocked and the rules for this lake. At 37°F on the surface right now, here is how each one should behave.
- FairWalleye
Cold. Slow jigs on deep structure.
- FairNorthern pike
Cold. Slow baits near weed edges and drop-offs.
- SlowLargemouth bass
Cold and sluggish. Fish slow and deep near steep banks.
- FairYellow perch
Cold. Deep schools; small jigs or minnows.
- SlowBluegill and sunfish
Cold. Deep and hard to tempt. Use tiny baits.
From today's water temperature and the season. A guide, not a promise.
Fishing spots
- 1Back of a cove
Sheltered, shallower water where baitfish gather.
- 2
- 3
- 4
- 5
- 6
- 7
6 more spots with LakeScope PRO: fish, depth band, water temperature, best time and bait for each.
Picked from the shape of the lake bed. A guide, not a promise.
Water temperature
At the surface, seen .
Water level
No daily level reading for this lake.
Ice
Open water
Ice thickness is an estimate from air temperature, not a measurement. Check the ice yourself before going on it.
Weather and wind
Sunrise 7:27 am · sunset 4:49 pm · waxing crescent moon (lake time).
Towns and places to stay near Union Lake
- Fosstonabout 14 mi east
- Mahnomenabout 19 mi south
- Red Lake Fallsabout 21 mi northwest
- Crookstonabout 26 mi northwest
- Grand Forksnearest city, about 49 mi northwest
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Questions about Union Lake
What fish are in Union Lake?
Lakes like Union Lake usually hold walleye, northern pike, largemouth bass, yellow perch and bluegill and sunfish. Check the state fish and wildlife agency for stocking and limits.
How deep is Union Lake?
We have no published depth for this lake. The 3-D view gives an estimated shape of the bed: where the deep basin and the drop-offs are. Not for navigation.
How big is Union Lake?
About 780 acres, with about 11 miles of shoreline.
What town is near Union Lake?
Fosston is about 14 miles east; Mahnomen is about 19 miles south.
What is the water temperature at Union Lake today?
The surface was about 37°F on the latest clear reading. The page updates every day.
Union Lake on your phone
The whole week of bite times, lake alerts and the 3-D view, every morning.
