NWS-Milwaukee/Sullivan Forecast Discussion

						FXUS63 KMKX 052145
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
116 PM CDT Sat Sep 5 2026

.KEY MESSAGES...

- Patchy dense fog possible over south central WI for early
  Sunday morning, especially in the WI River and Baraboo River
  Valleys.

- Mild and pleasant for Sunday and Labor Day.

- Warmer temps and high humidity returns for Tuesday and
  Wednesday along with 50-80% chances for showers and
  thunderstorms Tuesday night.


&&

.SHORT TERM...
Issued 115 PM CDT Sat Sep 5 2026

Tonight through Sunday night:

As high pressure continues to build from Ontario into the nrn
Great Lakes through tnt, somewhat drier air will arrive on nely
winds. This will aid in breaking up the stratus from late this
afternoon into the evening. However, good radiational cooling
conditions tnt and residual moisture should result in areas of
fog over the low lying areas of south central WI.

High pressure over the nrn Great Lakes on Sunday will slowly
move to the lower Great Lakes for Labor Day, while high
amplitude upper ridging over the Great Plains moves to the Upper
MS River Valley. Pleasant, summer-like days are expected.

Gehring

&&

.LONG TERM...
Issued 115 PM CDT Sat Sep 5 2026

Monday night through Saturday:

The extended models have good agreement with this period. A
robust upper trough will eject newd from the Pacific NW into the
nrn high plains and Canadian Prairies early in the week. The
downstream upper ridge will begin to flatten and shift across
the Great Lakes on Tue in response to the low. The trailing cold
front to the occluded low over Canada will move across srn WI
Wed AM. Very warm and humid conditions will return ahead of the
front for Tue into Wed. PWATs will rise to nearly 2 inches once
again, while high temps well into the 80s will be possible.
Showers and storm chances are at 50-80 percent for Tue nt.

Nwly flow aloft will briefly return afterward with a sfc ridge
shifting across the wrn Great Lakes. Temps will return to near
seasonal normals. Sly winds and warm, moist advection will
return by the end of the week with an approaching sfc trough
from the west. There are 20 percent chances for showers and
storms Fri nt-Sat at this time.

Gehring

&&

.AVIATION...
Issued 115 PM CDT Sat Sep 5 2026

Widespread MVFR Cigs with local Cigs below 1 kft this afternoon,
becoming VFR toward sunset. Areas of BR and fog to then develop
late tnt over south central WI and last through 14Z Sunday. The
WI River and Baraboo River Valleys could see a few hours of
dense fog. VFR conditions return for late Sunday morning through
the afternoon. Scattered fair weather cumulus around 4-4.5 kft
can be expected.

Gehring

&&

.MARINE...
Issued 115 PM CDT Sat Sep 5 2026

Light to modest east northeast winds this afternoon and
tonight. High pressure around 30.1 inches will build into the
northern Great Lakes tonight and Sunday and shift to the lower
Great Lakes for Monday. Light and variable winds are forecast
for Sunday and Monday.

Gehring

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...None.
LM...None.
&&

$$

Visit us at weather.gov/milwaukee

Follow us on Facebook, X, and YouTube at:
www.facebook.com/NWSMilwaukee
www.x.com/NWSMilwaukee
www.youtube.com/NWSMilwaukee