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Thompson: Big glacial bowl — walleye primary as nights cool
Monday Sep 21 – Thursday Sep 24, 2026 · Lake Thompson · bank, kayak & boat · Monday morning through Thursday evening focus · times CT
Classic northeast SD transition week. Lead walleye; perch and pike ride shotgun.
Midweek outlook
**NWS** pin forecast for Lake Thompson (pulled Sun Sep 20 ~8:45–8:55 PM CT). Monday reads **Rain Showers then Cloudy** (~57°F); Thursday trends **Rain Showers Likely** (~67°F). All clock times **CT**.
Barometer: K6E5 baro ~30.14 in, air ~59°F at pull. Clarity unconfirmed — do not invent stain.
Mon–Thuthrough Thu evening CT
walleyelocalized — not bass-by-default
Weekday recreational soft Mon–Thu after residual weekend traffic Monday. No named trail event pulled for this window on this water — re-check local clubs before launch.
Monday
- High ~57°F / night ~44°F **CT** · 10 to 15 mph ENE · PoP ~80%
- Rain Showers then Cloudy
- Primary **walleye**: fish weather pauses and forage edges — not a bass-by-default week.
Tuesday
- High ~62°F / night ~45°F **CT** · 5 to 10 mph ESE · PoP ~0%
- Mostly Sunny
- Primary **walleye**: fish weather pauses and forage edges — not a bass-by-default week.
Wednesday
- High ~65°F / night ~49°F **CT** · 15 to 20 mph SSE · PoP ~12%
- Partly Sunny
- Primary **walleye**: fish weather pauses and forage edges — not a bass-by-default week.
Thursday
- High ~67°F / night ~52°F **CT** · 10 to 20 mph S · PoP ~56%
- Rain Showers Likely
- Primary **walleye**: fish weather pauses and forage edges — not a bass-by-default week.
Verify local CT sunrise/sunset at pin (~7:05–7:10 AM CT class Monday Pierre/Watertown corridor). All Cast times CT.
Generator / pool cheat sheet
No generator schedule — glacial / natural-lake product. Weather and forage drive the window.
| Lake | Sun observed | Inflow / release | Notes |
|---|---|---|---|
| — | no dam board | natural / no gen | N/A |
SD GFP glacial
Primary story: walleye. Secondaries: yellow perch, northern pike, black bass.
Failover
Re-check USACE/USBR/NWS boards before launch — Sunday numbers age fast.
Schedules change without notice — re-check USACE / USBR / NWS before launch.
How to fish it — Bank / Kayak / Boat
Bank
- Dawn/dusk points and riprap with live bait or a slow jig — walleye first.
- Wind-blown banks after showers if safe.
- Watch slippery clay launches after Monday rain.
Kayak
- Parallel rock transitions and current seams (mainstem) or weed edges (glacial).
- Stake lightly — September walleye slide deeper midday.
- PFD on; midweek SW winds can stack chop on big water.
Boat
- Graph bait and follow birds/white-bass boils to find walleye underneath.
- Lead-core or snap-weights along breaks if wind allows.
- Idle zones near ramps if weekend leftovers linger Monday.
Lure box — Top / Mid / Bottom
Top
- Small buzz/walker only if bait is breaking — otherwise skip topwater.
- Long-bomb crank only on rare calm windows.
- Whites/SMB may crash bait — keep one reaction rod ready.
Mid
- Shad-profile cranks and swimbaits along windward breaks.
- Spinner harness + crawler where effective.
- Hair jig or soft plastic on rock for SMB bycatch.
Bottom
- Jig + minnow/plastic on points and river channel edges.
- Live-bait rig off the break as nights cool.
- Blade bait / hair jig when wind stands fish up.
Stain/clear: Clarity unconfirmed at pull — start natural/chrome and darken only if you see stain.
Life stage + What’s on the menu
**Late summer → early fall transition.** Cooler nights pulling **walleye** toward breaks and bait schools. Residual mild afternoons Wednesday–Thursday.
**What’s on the menu** (seasonal, not a dated hatch): YOY shad/minnows on mainstem; perch and invertebrates on glacial lakes. Match profile — do not invent a hatch date.
Ethanol-free fuel near this water
Pure-Gas.org E0 · near this water
Source: Pure-Gas.orgpulled Sun Sep 20, 2026 ~8:55 PM CT. Current prices — may change; verify at the pump.
- Cenex, 101 N Main, Lake Preston, SD — ~5.5 mi · E0 listing · Ethanol-free CENEX 91; GPS entered by jim bobprice not listed — verify at pump
- Jake's Corner, 44111 Hwy 34, Winfred, SD — ~20.4 mi · E0 listing · Ethanol-free SINCLAIR 87 91; GPS located from addressprice not listed — verify at pump
- Alsville Crossing, 45401 192nd St, Lake Norden, SD — ~25.4 mi · E0 listing · Ethanol-free SINCLAIR 87 91; GPS entered by Steve Olsonprice not listed — verify at pump
- T & C's Pit Stop, 25315 Us Hwy 81 S, Salem, SD — ~29.3 mi · E0 listing · Ethanol-free CENEX 91; GPS located from addressprice not listed — verify at pump
Also hot / also in season
- yellow perch — honest secondary this week
- northern pike — honest secondary this week
- black bass — honest secondary this week
- Regs: SD GFP Fishinglive-check only — do not hardcode inches/creel.
Regs: live-check only — never hardcode length/creel in Cast text.