NWS-Milwaukee/Sullivan Forecast Discussion

						FXUS63 KMKX 211824
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
124 PM CDT Sun Jun 21 2026

.KEY MESSAGES...

- Rain is delayed today but still looking likely from Madison to
  Milwaukee and south to the IL border for mid afternoon and
  evening. Around one half inch of rain is expected toward the
  IL border.

- At least Moderate Swim Risk is expected for the Lake Michigan
  beaches Monday with the possibility for High Swim Risk to
  develop. Keep out of the water and away from dangerous areas
  like piers and breakwalls!

- Chances for thunderstorms Tue nt through Wed nt.

- Below normal temps continue.


&&

.SHORT TERM...
Issued 124 PM CDT Sun Jun 21 2026

Tonight through Monday night:

Delayed onset of rain today but still expecting 60-90 percent
chances along and south of a line from Madison to Milwaukee for
mid to late afternoon and into the evening. The shield of rain
is finally moving into far srn WI. A couple vorticity maximums
across nrn IA will move across far srn WI late this afternoon
and evening. These features and associated PVA, along with mid
level warm advection and frontogenesis reaching the WI and IL
border, may be enough for measurable light rain as far north as
Madison and Milwaukee. Moderate rainfall rates are still
expected at times near the IL border with rainfall totals around
one half inch there. Showers will then linger over far se WI in
the early morning hours with skies becoming partly cloudy
afterward. Nely sfc winds and cold advection will prevail
through the morning. Scattered cumulus to brief broken cumulus
can then be expected for Mon afternoon well inland from Lake
MI. High temps will range from the 60s at the Lake MI shoreline
with middle 70s well inland. A north to south sfc ridge will
then slowly move across srn WI Mon nt-Tue. High temps on Tue
will be slightly higher for Tue.

Gehring

&&

.LONG TERM...
Issued 124 PM CDT Sun Jun 21 2026

Tuesday night through Sunday:

A slow moving shortwave trough and weak sfc low will then track
from srn Canada across the nrn Great Lakes for Wed-Thu. Rain
chances of 50-80 percent will begin Tue nt and last into Wed.
Thunderstorms will be possible during this time. Lingering
precipitation is then possible Thu followed by high pressure for
Thu nt-Fri. Upper ridging will then take hold over the region
for the weekend as cyclogenesis ensues over the Canadian
Prairies. A dry esely flow will limit rain chances with possibly
some increase in moisture by Sunday. Slightly below normal temps
for the middle of the week may eventually become above normal by
Sunday.

Gehring

&&

.AVIATION...
Issued 124 PM CDT Sun Jun 21 2026

Widespread rainfall will move from IL into srn WI through the
afternoon and continue into the evening mainly along and south
of a line from Madison to Milwaukee. Areas of MVFR Cigs and
Vsbys can be expected with the rain over far srn WI but
extending into the MKE metro area during the evening. The low
Cigs and lingering rain showers will continue into early Tue AM
from MKE south to ENW. Partly cloudy skies and VFR conditions
will then return for the daylight hours of Tue.

Gehring

&&

.MARINE...
Issued 124 PM CDT Sun Jun 21 2026

Low pressure around 29.7 inches will track eastward from
northeast Missouri into western Ohio by Monday morning. This
will bring light easterly winds this afternoon becoming breezy
northeast to north winds over the southern portion of the lake
tonight and Monday. Lighter northerly winds return late Monday
evening into Tuesday as high pressure around 30.1 inches builds
into the region. A Small Craft Advisory may be needed on Monday
from Sheboygan to Winthrop Harbor IL, but there is still some
uncertainty with the magnitude of nly winds and resultant wave
heights.

Gehring

&&

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

$$

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