Lake depth chart
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Rating depth structure for largemouth bass.
Recent public catches load as you reach this section.
381-acre lake near Schoolcraft County. The lake tops out around 20 ft. The depth chart comes from published agency bathymetric survey data, so the contours are survey-derived rather than computer-modeled. Below is the species-by-species picture, pulled from the same data the map uses.
Thunder Lake maps at 367 acres behind 4.1 miles of shoreline. A middling shoreline index (1.5) gives it some bays to work without being a maze. Roughly 91% of the water is 15 ft or less, the band where the food chain lives. Figure 1.6 mi of water from one end to the other, 0.7 mi at the beam. It sits in Schoolcraft County. Its nearest charted neighbour, Bear Lake, is 2 mi to the southwest.
The spring pattern is a shallow one: walleye in 4 to 15 ft. Midsummer fish sit out in 6 to 20 ft before dropping to 6 to 20 ft for winter. The spot to know is Break off the point, a drop-off in about 6 ft of water that rates prime for walleye in fall. Plan around the evening and early morning in the warm months. Summer baits: a crawler harness on bottom bouncer or a deep crankbait (trolled) gets it done.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 4 to 15 ft | dusk & dawn | Main-lake point (4 ft) | 1/8 oz jig + minnow, Hair jig |
| Summer | 6 to 20 ft chart-limited; documented 15 to 35 ft | dusk & dawn | Break off the point (6 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 6 to 20 ft chart-limited; documented 12 to 40 ft | dusk & night | Break off the point (6 ft) | Jigging rap, Jig + big minnow |
| Winter | 6 to 20 ft chart-limited; documented 20 to 40 ft | dusk & dawn | Deep basin (20 ft) | Jigging spoon + minnow head, Rattle bait |
In spring, yellow perch run shallow here, mostly 3 to 12 ft. Midsummer fish sit out in 6 to 20 ft before dropping to 6 to 20 ft for winter. Fall yellow perch concentrate at Deep basin, a prime-rated deep basin around 20 ft. Fish it in early morning and you'll meet the bite. You won't need more than a drop-shot micro plastics or a small spoon tipped with worm most summer days.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | midday & dawn | Shallow bay flat (1 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 6 to 20 ft chart-limited; documented 10 to 30 ft | dawn | Deep basin (20 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 6 to 20 ft chart-limited; documented 12 to 35 ft | midday | Deep basin (20 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 6 to 20 ft chart-limited; documented 15 to 35 ft | midday & dawn | Deep basin (20 ft) | Tungsten jig + spikes, Rattle spoon (small) |
Early season smallmouth bass use the shallows, holding in 3 to 12 ft. Summer is a 6 to 20 ft game here, winter a 6 to 20 ft one. The chart's best answer is Break off the point — drop-off, 6 ft, prime for winter. Best bite is early morning and the evening. Tie on a drop shot (goby/minnow) or a ned rig and you're in the game.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | dawn & dusk | Main-lake point (4 ft) | Ned rig, Tube jig |
| Summer | 6 to 20 ft chart-limited; documented 10 to 30 ft | dawn & dusk | Break off the point (6 ft) | Drop shot (goby/minnow), Ned rig |
| Fall | 6 to 20 ft chart-limited; documented 8 to 25 ft | midday & dawn | Break off the point (6 ft) | Jerkbait, Blade bait |
| Winter | 6 to 20 ft chart-limited; documented 20 to 45 ft | midday | Break off the point (6 ft) | Blade bait, Hair jig |
Spring largemouth bass on Thunder Lake hold shallow, usually 2 to 10 ft. They move out to 8 to 20 ft in summer and finish the year down in 6 to 20 ft. Put Main-lake point first on the milk run — a point near 4 ft that grades prime for fall. The feeding windows run early morning and the evening. The summer box starts with a texas-rigged 10" worm or a deep-diving crankbait.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 10 ft | dawn & dusk | Shallow bay flat (1 ft) | Spinnerbait, Chatterbait |
| Summer | 8 to 20 ft | dawn & dusk | Break off the point (6 ft) | Texas-rigged 10" worm, Deep-diving crankbait |
| Fall | 4 to 15 ft | midday & dawn | Main-lake point (4 ft) | Squarebill crankbait (shad), Spinnerbait |
| Winter | 6 to 20 ft chart-limited; documented 15 to 35 ft | midday | Break off the point (6 ft) | Blade bait, Jigging spoon |
Early season crappie use the shallows, holding in 2 to 8 ft. Summer is a 6 to 20 ft game here, winter a 6 to 20 ft one. The chart's best answer is Deep basin — deep basin, 20 ft, prime for winter. Best bite is early morning and the evening. Tie on a jig trolled/spider-rigged or a small crankbait (trolled) and you're in the game.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 8 ft | midday & dawn | Shallow bay flat (1 ft) | 1/16 oz jig + tube, Curly-tail grub |
| Summer | 6 to 20 ft chart-limited; documented 10 to 25 ft | dawn & dusk | Break off the point (6 ft) | Jig trolled/spider-rigged, Small crankbait (trolled) |
| Fall | 8 to 20 ft | dawn | Deep basin (20 ft) | Jig + minnow combo, Small swimbait (1.5-2") |
| Winter | 6 to 20 ft chart-limited; documented 15 to 35 ft | midday | Deep basin (20 ft) | Tungsten jig + soft plastic, Tiny jigging spoon |
Early season bluegill use the shallows, holding in 1 to 6 ft. Expect a summer slide to 4 to 15 ft, then a winter hold in 6 to 20 ft. Put Shallow bay flat first on the milk run — a weed flat near 1 ft that grades prime for spring. In summer the feeding windows fall in early morning and the evening. Tie on a small sponge spider (fly) or a micro tube jig and you're in the game.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 1 to 6 ft | midday & dusk | Shallow bay flat (1 ft) | 1/32 oz jig + micro plastic, Tiny popper (evenings) |
| Summer | 4 to 15 ft | dawn & dusk | Shallow bay flat (1 ft) | Small sponge spider (fly), Micro tube jig |
| Fall | 6 to 18 ft | midday | Break off the point (6 ft) | Micro jig + waxworm, Small spoon tipped |
| Winter | 6 to 20 ft chart-limited; documented 10 to 25 ft | midday | Deep basin (20 ft) | Tungsten ice jig + plastic, Tiny spoon |
Thunder Lake also holds northern pike (8 to 20 ft in summer). Pick any of them on the map above for rated spots and bait picks.
Thunder Lake carries 6 mapped structure features, topping out (or rather bottoming out) at Deep basin, about 20 ft down.
Season dates, license requirements, and size and bag limits for Michigan waters are set by the Michigan DNR — and special regulations can apply to Thunder Lake specifically, so confirm the current rules before you fish.
Check the official Michigan fishing regulations →
Thunder Lake is about 20 ft (6 m) deep at its deepest point. The depth chart comes from published agency bathymetric survey data, so the contours are survey-derived rather than computer-modeled.
Anglers target walleye, yellow perch, smallmouth bass, largemouth bass, crappie, bluegill, northern pike on Thunder Lake. This isn't a survey of the water — none is published for it — but an informed estimate from the species common to the region, narrowed by this water's depth, size and each species' range.
Break off the point is the top-rated area: a drop-off in about 6 ft of water that rates prime for walleye in fall. The map above holds the full rated-spot list for every species and season.
For walleye, the summer bite is best in the evening and early morning. Each species page section below lists the seasonal windows, and the map shows a live NOW badge when you're inside one.
Fishing on Thunder Lake is regulated by the Michigan DNR. Check the official Michigan regulations for current license requirements, season dates, and size and bag limits — special regulations can apply to this specific water.
Bear Lake 2 mi · Murphy Lake 2 mi · Muleshoe Lake, North 3 mi · Minerva Lake 3 mi · Lyman Lake 4 mi · Gooseneck Lake 4 mi · Bass Lake 5 mi · Camp Seven Lake 5 mi · Triangle Lake 5 mi · Mowe Lake 6 mi · Ironjaw Lake 6 mi · East Lake 6 mi
See how Thunder Lake stacks up: best largemouth bass lakes in Michigan · best smallmouth bass lakes in Michigan · best walleye lakes in Michigan · best northern pike lakes in Michigan
More water nearby: Schoolcraft County fishing maps (54 charts). Browse all Michigan fishing maps. See every water on DepthScout. Bathymetry: published agency survey data. How we build these maps. Fish here with a sonar unit that logs? Send us your depth data and we'll improve this chart, credited to you. For fishing guidance only, never navigation.