Where to fish

  • Forecast
  • Catches

Mine

  • Favorites

Where to fish

  • Forecast
  • Catches

Mine

  • Favorites
ForecastCatchesFavorites
AboutHow the forecast worksWhere fish livePrivacyTerms[email protected]
© 2026·AI-powered bite forecast
0.1.0+2163 · 92c14a40

We use cookies for analytics and advertising. Cookies necessary for the site to function are always kept. Learn more

United States / Wisconsin / Union Bay

Bite forecast: Union Bay

  • 344 acres
Loading map…

Best fishing days for the next week

  1. TuesdaySeptember 8weather-based forecast
    74/100high activity

    Cloudy: 61–90 °F

  2. MondaySeptember 7weather-based forecast
    73/100high activity

    Drizzle: 57–79 °F

  3. WednesdaySeptember 9weather-based forecast
    68/100high activity

    Partly cloudy: 59–86 °F

Union Bay (Wisconsin) — a popular fishing spot. About 1.4 km² in area. This is a sea water — its bite forecast is a marine one, computed apart from rivers and lakes. See when the bite is best: hourly fish activity for the days ahead, computed from the weather, pressure, and season.

Loading map…

Bite calendar

Thursday, September 3

Aug 31 – Sep 6
Mon
Tue
Wed
Thu
Fri
Sat
Sun
Bite activity:highmediumlowslow
Based on:weatherseasonal
What is a bite calendar?
Coho salmonSteelheadChinook salmon

Coho salmon

7/10 · Good

Hourly activity

0:006:0012:0018:0023:00
Bite activity:highmediumlow

The bite is strong — fish are active. Weather is steady, with no sharp swings — fish behave predictably.

Peak bite hours

Best time — 06:00–08:00 (dawn bite) and 19:00–21:00 (dusk bite).

Tactics

Look for structure — reefs, flats, channel edges; work them slowly near the bottom.

Lures

The water's turning murky — go with bright, noisy lures: trolling spoon or spinner.

Gear

It's a hot day — a hat, sunglasses, and plenty of water are a must. Rain is expected — don't forget a rain jacket or a waterproof shell.

Summary

Worth going — it's a productive day.

How this forecast is calculated

Why this forecast

The computed water temperature is around 67 °F — warmer than the 43–59 °F comfort range for Coho salmon: in the heat it drops deeper and feeds less often.

Computed water temperature by month; the green band is the 43–59 °F comfort rangecomfort 43–59 °F67 °F
JFMAMJJASOND

Coho salmon works the twilight: the peaks are pinned to sunrise and sunset — their times are in the sun-and-moon card above.

The day: daylight hours and when Coho salmon feeds0:0012:0024:00

Pressure is flat: it moves no more than 0.03 inHg over the day, so the weather isn't shifting today's bite.

Pressure through the day, 0.03 inHg change
00:00 · 29.8723:00 · 29.90 inHg

One more input — the moon's feeding windows: within their hours the score sits higher than across the rest of the day. The window times are in the “Solunar feeding periods” card below.

Feeding windows on the day scale0:0012:0024:00

September is peak season for Coho salmon here.

JFMAMJJASOND

These are the same values the bite curve above was computed from. How the forecast works

Water

Wave
0.6 ft
Period
2 s

Open-Meteo Marine model, grid cell 3.7 mi from the waterbody. Values are daily means.

3 SepThursday, September 3
+73°

Drizzle · feels like +74°

Low / high
+60°…+78°
Precipitation
0.03 in
Wind
8 mph SSW
Cloud cover
100%
Humidity
69%
Pressure
29.91 inHg
00:00+66°—7 mpheast wind, 7 mph56%0%
01:00+64°—6 mphnortheast wind, 6 mph58%0%
02:00+64°—5 mphnortheast wind, 5 mph60%0%
03:00+62°—3 mphnortheast wind, 3 mph64%0%
04:00+61°—4 mphnortheast wind, 4 mph72%0%
05:00+61°—4 mphnortheast wind, 4 mph80%0%
06:00+60°—5 mpheast wind, 5 mph86%1%
07:00+61°—5 mpheast wind, 5 mph87%1%
08:00+65°—7 mpheast wind, 7 mph79%1%
09:00+69°—5 mpheast wind, 5 mph72%100%
10:00+73°—7 mpheast wind, 7 mph65%100%
11:00+75°—4 mphsoutheast wind, 4 mph61%100%
12:00+73°0.03 in8 mphsouth wind, 8 mph69%100%
13:00+70°—5 mphsouth wind, 5 mph92%100%
14:00+74°—6 mphsouthwest wind, 6 mph82%100%
15:00+77°—3 mphsouthwest wind, 3 mph74%100%
16:00+78°—1 mphsouthwest wind, 1 mph68%100%
17:00+78°—4 mphsouthwest wind, 4 mph68%100%
18:00+77°—2 mphsouth wind, 2 mph70%100%
19:00+75°—4 mphsouth wind, 4 mph78%76%
20:00+73°—5 mphsouth wind, 5 mph79%100%
21:00+72°—6 mphsouth wind, 6 mph84%81%
22:00+71°—2 mphsouthwest wind, 2 mph87%100%
23:00+70°—4 mphsoutheast wind, 4 mph86%26%
+78°+69°+60°
Weather throughout the day
0:006:0012:0018:0023:00

Sun and moon

Thursday, September 3
The day: daylight and the hours the moon is above the horizon. Local time0:0012:0024:00
DaylightMoon above the horizon
Sunrise
06:22
Sunset
19:32
Day length
13 h 10 min
Sunshine hours
6 h
UV index
5
moderate
Moon
Last quarter
Moonrise
22:22
Moonset
14:19

The day is 3 min shorter than yesterday.

Sunshine hours count direct sun only — cloud cover cuts it, so it is shorter than daylight.

Solunar feeding periods

+13% in the windowThursday, September 3
Feeding windows on the day scale, local time0:0012:0024:00
Major periodsMinor periods
  • Major04:53–06:53Moon overhead
  • Minor13:49–14:49Moonset
  • Major17:23–19:23Moon underfoot
  • Minor21:52–22:52Moonrise

The windows are set by the moon's transit and rise, and the forecast above already accounts for them: within these hours the bite score sits higher than across the rest of the day, while the day's overall level still comes from the catch-calibrated model.

What are solunar periods?

Nearby rivers

  • Union River0.5 mi
  • Upper Carp River4 mi
  • Little Iron River5 mi
  • Mineral River7 mi
  • East Branch Duck River8 mi
  • Big Carp River9 mi

Nearby water bodies

  • BayUnion Bay0 mi
  • BayUnion Bay0 mi
  • LakeLost Lake5 mi
  • LakeLake of the Clouds6 mi
  • LakeMirror Lake8 mi