Fishing Forecast · Wisconsin · Updated August 2026

Lake Koshkonong

Lake Koshkonong earns a D for water quality. This forecast reads its measured clarity, depth, and trophic state — with each species' biology, the sun and moon, and today's conditions — to call when the fish move on Lake Koshkonong and how to catch them.

7 ft
max depth: 7
fish species: 1.7 ft
water clarity: Hypereutrophic
trophic state

Today · Fri Aug 7

★★★★★

The bite on Lake Koshkonong today. Sunrise 5:53 AM, sunset 8:09 PM.

Moon: Waning Crescent · 32%
Major windows: 6:26 PM–8:26 PM · 6:55 AM–8:55 AM

Best day · next 2 weeks

Thu Aug 13

★★★★★

New Moon moon (0%). Fish the major windows at 12:27 AM and 12:53 PM.

Fishing Forecast for Lake Koshkonong

A multi-factor outlook built from Lake Koshkonong's measured water quality — clarity, trophic state, depth, and water-body type — combined with each species' biology, seasonal patterns, and today's live weather. It flags spawn timing, where the fish hold, and the techniques that fit this lake's water, not just the moon.

Walleye

Game FishSummerSummer pattern

Fair

~75°F est.

Lake Koshkonong runs 1.7 ft of clarity and grades D for water quality — which plays right into walleye — work vibration, rattle, and bright colors, and the fish use light more freely through the day.

Because Lake Koshkonong averages 1.7 ft of visibility (stained/turbid), which plays right into walleye — work vibration, rattle, and bright colors, and the fish use light more freely through the day.
Its hypereutrophic nutrient level puts the summer weedline near 4–8 ft — that edge is the high-percentage zone to hold walleye through the warm months.
With a max depth of 7 ft, Lake Koshkonong is a shallow lake that stays mixed and warm all summer — fish relate to weeds, wind, and cover rather than depth.

Techniques for stained water

bladed/rattling baits for vibrationbrighter jigs & crankbaitswork the windblown "walleye chop"

Season-by-season on Lake Koshkonong

Season	Where	Structure	How
Spring	shallow 3–10 ft	rock/gravel bars, warming shoreline, river mouths	jig-and-minnow, slow-rolled swimbaits
Summer	mid-depth 12–25 ft	main-lake points, mid-lake humps, weed edges	live-bait rigs, bottom bouncers/crawler harnesses
Fall	variable 8–30 ft	steep breaks and points as they feed up	jigging bigger minnows, trolling deep cranks
Winter / Ice	8–25 ft	first breaks off structure, dusk feeding windows	jigging spoons and rattle baits, deadstick minnows

Smallmouth Bass

Game FishSummerSummer pattern

Slow

~75°F est.

Lake Koshkonong runs 1.7 ft of clarity and grades D for water quality — so add vibration, rattle, and brighter colors to help fish find your bait.

Because Lake Koshkonong averages 1.7 ft of visibility (stained/turbid), so add vibration, rattle, and brighter colors to help fish find your bait.
Its hypereutrophic nutrient level puts the summer weedline near 4–8 ft — that edge is the high-percentage zone to hold smallmouth bass through the warm months.
With a max depth of 7 ft, Lake Koshkonong is a shallow lake that stays mixed and warm all summer — fish relate to weeds, wind, and cover rather than depth.

Techniques for stained water

spinnerbaits & bladed jigs for vibrationbrighter colors — but seek the clearest water available

Season-by-season on Lake Koshkonong

Season	Where	Structure	How
Spring	shallow 4–12 ft	rocky flats, gravel points, boulder shoals	tubes, ned rigs, jerkbaits
Summer	mid 10–25 ft	main-lake rock, reefs, deep points	drop-shot, tubes, deep cranks
Fall	variable 8–30 ft	rock structure, baitfish schools	jerkbaits, blade baits, hair jigs
Winter / Ice	deep 20–40 ft	deep rock (open-water fishery where legal)	slow blade baits, hair jigs

Largemouth Bass

Game FishSummerSummer pattern

Very Good

~75°F est.

Lake Koshkonong runs 1.7 ft of clarity and grades D for water quality — so add vibration, rattle, and brighter colors to help fish find your bait.

Because Lake Koshkonong averages 1.7 ft of visibility (stained/turbid), so add vibration, rattle, and brighter colors to help fish find your bait.
Its hypereutrophic nutrient level puts the summer weedline near 4–8 ft — that edge is the high-percentage zone to hold largemouth bass through the warm months.
With a max depth of 7 ft, Lake Koshkonong is a shallow lake that stays mixed and warm all summer — fish relate to weeds, wind, and cover rather than depth.

Techniques for stained water

reaction baits: chatterbait, dark jigsthump/vibration & dark silhouettesflip heavy cover

Season-by-season on Lake Koshkonong

Season	Where	Structure	How
Spring	shallow 1–6 ft	protected bays, pads, laydowns, warming flats	soft plastics, jigs, lipless cranks pre-spawn
Summer	shallow-to-mid 3–15 ft	weed edges, docks, lily pads, deep weedlines	topwater at dawn/dusk, Texas-rigged plastics, frogs
Fall	shallow 2–10 ft	bays chasing baitfish, remaining green weeds	spinnerbaits, squarebill cranks, chatterbaits
Winter / Ice	deep 12–25 ft	main-lake basin edges (largely dormant in the north)	slow finesse — a marginal cold-water bite

Muskellunge

Game FishSummerSummer pattern

Slow

~75°F est.

Lake Koshkonong runs 1.7 ft of clarity and grades D for water quality — so add vibration, rattle, and brighter colors to help fish find your bait.

Because Lake Koshkonong averages 1.7 ft of visibility (stained/turbid), so add vibration, rattle, and brighter colors to help fish find your bait.
Its hypereutrophic nutrient level puts the summer weedline near 4–8 ft — that edge is the high-percentage zone to hold muskellunge through the warm months.
With a max depth of 7 ft, Lake Koshkonong is a shallow lake that stays mixed and warm all summer — fish relate to weeds, wind, and cover rather than depth.

Techniques for stained water

rubber/rattling baitsbright, big-profile, high-vibration

Season-by-season on Lake Koshkonong

Season	Where	Structure	How
Spring	shallow 3–10 ft	warming weed flats, bays	bucktails, smaller glide baits
Summer	weed & rock 6–20 ft	big weed flats, rock bars, open-water basins	bucktails, topwater, crankbaits
Fall	variable 8–35 ft	deep structure, cisco lakes, big-bait zones	large soft baits & suckers — prime trophy window
Winter / Ice	n/a	season typically closed	catch-and-release ethic; check regulations

Muskie fisheries depend on careful catch-and-release; use proper release tools and check size limits.

Northern Pike

Game FishSummerSummer pattern

Fair

~75°F est.

Lake Koshkonong runs 1.7 ft of clarity and grades D for water quality — so add vibration, rattle, and brighter colors to help fish find your bait.

Because Lake Koshkonong averages 1.7 ft of visibility (stained/turbid), so add vibration, rattle, and brighter colors to help fish find your bait.
Its hypereutrophic nutrient level puts the summer weedline near 4–8 ft — that edge is the high-percentage zone to hold northern pike through the warm months.
With a max depth of 7 ft, Lake Koshkonong is a shallow lake that stays mixed and warm all summer — fish relate to weeds, wind, and cover rather than depth.

Techniques for stained water

bladed & rattling baitsbright chartreuse/orange, big profile

Season-by-season on Lake Koshkonong

Season	Where	Structure	How
Spring	shallow 2–8 ft	weedy bays, marsh mouths, warming flats	spoons, spinnerbaits, big soft plastics
Summer	weed edges 6–18 ft; big pike deeper/cooler	cabbage/coontail edges, deep weedlines, cool water	large spoons, jerkbaits, dead-bait for big fish
Fall	variable 6–25 ft	deep weed edges, drop-offs, cisco/tullibee lakes	big swimbaits, sucker/dead-bait rigs — trophy season
Winter / Ice	6–20 ft	weed edges and flats	tip-ups with large shiners/suckers

Panfish

PanfishSummerSummer pattern

Very Good

~75°F est.

Lake Koshkonong runs 1.7 ft of clarity and grades D for water quality — so add vibration, rattle, and brighter colors to help fish find your bait.

Because Lake Koshkonong averages 1.7 ft of visibility (stained/turbid), so add vibration, rattle, and brighter colors to help fish find your bait.
Its hypereutrophic nutrient level puts the summer weedline near 4–8 ft — that edge is the high-percentage zone to hold panfish through the warm months.
With a max depth of 7 ft, Lake Koshkonong is a shallow lake that stays mixed and warm all summer — fish relate to weeds, wind, and cover rather than depth.

Techniques for stained water

brighter jigs, scent, slower presentation

Season-by-season on Lake Koshkonong

Season	Where	Structure	How
Spring	shallow 2–8 ft	warming bays, weed and brush cover	small jigs and live bait under a float
Summer	weed edges 6–18 ft	deeper weedlines, docks, brush	small jigs, slip-bobbers, live bait
Fall	mid 8–20 ft	deeper weed edges and basin	small jigs and spoons
Winter / Ice	8–25 ft	basin holes and deep weed edges	tungsten ice jigs with waxworms/minnows

The outlook is a transparent heuristic weighting of established angling factors, this lake's measured water quality, and live conditions — not a validated catch predictor. Water temperature is estimated from season and latitude unless a recent USGS gauge reading is available. Planning a meal? Check fish-consumption advisories for Lake Koshkonong. Always follow current state regulations.

14-Day Fishing Calendar

Plan the next two weeks on Lake Koshkonong. Anglers target Musky, Panfish, Largemouth Bass, Smallmouth Bass, and others on Lake Koshkonong.

Date	Rating	Moon	Sunrise	Sunset	Major Periods	Minor Periods
Fri, Aug 7	☆☆☆☆☆	Waning Crescent 32% lit	5:53 AM	8:09 PM	6:26 PM – 8:26 PM 6:55 AM – 8:55 AM	11:23 PM – 12:23 AM 3:38 PM – 4:38 PM
Sat, Aug 8	☆☆☆☆☆	Waning Crescent 23% lit	5:54 AM	8:08 PM	7:26 PM – 9:26 PM 7:58 AM – 9:58 AM	12:11 AM – 1:11 AM 4:47 PM – 5:47 PM
Sun, Aug 9	☆☆☆☆☆	Waning Crescent 14% lit	5:55 AM	8:07 PM	8:30 PM – 10:30 PM 9:02 AM – 11:02 AM	1:12 AM – 2:12 AM 5:46 PM – 6:46 PM
Mon, Aug 10	½☆☆☆☆	Waning Crescent 8% lit	5:56 AM	8:05 PM	9:34 PM – 11:34 PM 10:05 AM – 12:05 PM	2:26 AM – 3:26 AM
Tue, Aug 11	★½☆☆☆	Waning Crescent 3% lit	5:57 AM	8:04 PM	10:36 PM – 12:36 AM 11:06 AM – 1:06 PM	6:33 PM – 7:33 PM 3:46 AM – 4:46 AM
Wed, Aug 12	★★☆☆☆	New Moon 0% lit	5:59 AM	8:02 PM	11:34 PM – 1:34 AM 12:01 PM – 2:01 PM	7:10 PM – 8:10 PM 5:08 AM – 6:08 AM
Thu, Aug 13	★★½☆☆	New Moon 0% lit	6:00 AM	8:01 PM	12:27 AM – 2:27 AM 12:53 PM – 2:53 PM	7:39 PM – 8:39 PM 6:27 AM – 7:27 AM
Fri, Aug 14	★½☆☆☆	Waxing Crescent 2% lit	6:01 AM	8:00 PM	1:17 AM – 3:17 AM 1:41 PM – 3:41 PM	8:04 PM – 9:04 PM 7:42 AM – 8:42 AM
Sat, Aug 15	★☆☆☆☆	Waxing Crescent 6% lit	6:02 AM	7:58 PM	2:04 AM – 4:04 AM 2:27 PM – 4:27 PM	8:26 PM – 9:26 PM 8:55 AM – 9:55 AM
Sun, Aug 16	☆☆☆☆☆	Waxing Crescent 12% lit	6:03 AM	7:57 PM	2:49 AM – 4:49 AM 3:12 PM – 5:12 PM	8:46 PM – 9:46 PM 10:05 AM – 11:05 AM
Mon, Aug 17	★☆☆☆☆	Waxing Crescent 20% lit	6:04 AM	7:55 PM	3:34 AM – 5:34 AM 3:57 PM – 5:57 PM	9:07 PM – 10:07 PM 11:14 AM – 12:14 PM
Tue, Aug 18	★½☆☆☆	Waxing Crescent 29% lit	6:05 AM	7:54 PM	4:19 AM – 6:19 AM 4:43 PM – 6:43 PM	9:30 PM – 10:30 PM 12:21 PM – 1:21 PM
Wed, Aug 19	★★½☆☆	Waxing Crescent 39% lit	6:06 AM	7:52 PM	5:06 AM – 7:06 AM 5:30 PM – 7:30 PM	9:56 PM – 10:56 PM 1:28 PM – 2:28 PM
Thu, Aug 20	★½☆☆☆	First Quarter 50% lit	6:07 AM	7:50 PM	5:55 AM – 7:55 AM	10:27 PM – 11:27 PM 2:31 PM – 3:31 PM

Server-rendered 14-day calendar starting 2026-08-07. Live in your browser shortly.

Methodology

How this forecast works

A plain solunar table only knows the moon. The LakeQuality Fishing Forecast starts there and adds what actually decides where and how fish bite on Lake Koshkonong — factors we measure rather than guess:

Water clarity — Lake Koshkonong's Secchi reading flips the playbook between clear-water finesse and stained-water reaction baits, and sets the low-light bite window.
Trophic state & depth — nutrient level and max depth set the summer weedline and whether the lake stratifies, which tells you how deep to fish.
Water-body type — natural lake vs. reservoir changes the structure that holds fish.
Species & season — each species' spawn-temperature window and seasonal movements, matched to the lake's estimated water temperature.
Sun & moon — the solunar major/minor periods and dawn/dusk twilight in the calendar below.

The species outlook is a transparent heuristic weighting of these established factors, and it now also factors in today's live conditions — wind, cloud cover, and the barometric (pressure) trend, recomputed for the current day. It's not a validated catch predictor, and water temperature is still an estimate from season and latitude unless a recent USGS gauge reading exists. It's the analysis a solunar table can't do, grounded in Lake Koshkonong's real, measured water quality.

How to read the calendar

Major periods (≈2 hours) are centered on lunar transit (when the moon is highest in the sky) and lunar opposition (when the moon is directly underfoot). These are typically the strongest feeding windows.

Minor periods (≈1 hour) are centered on moonrise and moonset. They're secondary windows that often produce well — especially when they coincide with sunrise or sunset.

Day rating combines moon phase (peak near new and full moons, when lunar gravity is strongest) with the overlap of major periods and the dawn/dusk twilight. A 4–5 star day stacks all three.

At Lake Koshkonong (lat 42.85°N), the longest day of the year is around June 21 with 15h 21m of daylight. The shortest is around December 21 with 9h 1m. Plan summer trips around the early-morning bite (around 5:30 AM) and the long evening window before sunset.

Frequently asked questions

What makes this better than a solunar fishing table for Lake Koshkonong?

A solunar table only uses the moon. The LakeQuality Fishing Forecast adds Lake Koshkonong's measured water quality — its stained water, trophic state, depth, and water-body type — matched to each species' spawn window and seasonal movements. That measured data drives where the fish hold and which techniques fit this lake's water, then the solunar calendar below adds the sun/moon timing. It's a transparent, multi-factor outlook, not a validated catch guarantee.

What is the best time to fish Lake Koshkonong today?

Today's solunar calendar for Lake Koshkonong (lat 42.85, lon -88.98) shows sunrise at 5:53 AM and sunset at 8:09 PM. The strongest fishing windows are around major solunar periods at 6:26 PM–8:26 PM and 6:55 AM–8:55 AM, plus the 30-90 minutes around dawn and dusk.

What does the moon phase mean for fishing Lake Koshkonong?

Solunar theory holds that fish activity peaks during major periods (when the moon is overhead or directly underfoot) and minor periods (moonrise and moonset). Fish feeding tends to intensify during the days surrounding the new moon and full moon, when lunar gravity is strongest. Today's moon at Lake Koshkonong is Waning Crescent (32% illuminated).

When are the longest and shortest days at Lake Koshkonong?

At Lake Koshkonong's latitude (42.85°N), the longest day of the year is around June 21 with about 15h 21m of daylight. The shortest day is around December 21 with about 9h 1m of daylight. Sunrise and sunset shift by roughly 6 hours between solstices.

Are major or minor solunar periods more important?

Major periods (about 2 hours, centered on lunar transit and lunar opposition) are generally considered the strongest feeding windows. Minor periods (about 1 hour, centered on moonrise and moonset) are secondary but still productive — especially when they overlap with sunrise or sunset.

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The species outlook is a transparent, multi-factor heuristic built from Lake Koshkonong's measured water quality (clarity, trophic state, depth, water-body type) and established species biology, and it now also factors in today's live conditions — wind, cloud cover, and the barometric (pressure) trend, recomputed for the current day. It's not a validated catch predictor, and water temperature is still an estimate from season and latitude unless a recent USGS gauge reading is available. Solunar times use lat/lon and Meeus astronomical formulas, shown in Central Time. Always check local regulations and current conditions before fishing.

Source: EPA National Aquatic Resource Surveys, 2026.

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