NWS-Milwaukee/Sullivan Forecast Discussion

						FXUS63 KMKX 120445
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
1145 PM CDT Mon May 11 2026

.KEY MESSAGES...

- A clipper system brings higher-end shower chances (50 to 80
  percent) for Tuesday morning. A passing cold front Tuesday
  afternoon may bring a few thunderstorms. Gusty winds and small
  hail may occur with the strongest storms, if they develop.

- A brief period of gales is possible over the middle third of
  the open waters of Lake Michigan late Tuesday morning into
  Tuesday afternoon.

- A cool and cloudy day is expected for Wednesday.

- Relatively warm and humid conditions with increasing storm
  chances returns from Thursday night into the weekend.

&&

.SHORT TERM...
Issued 1106 PM CDT Mon May 11 2026

Today through Wednesday night:

Low pressure will approach from the northeast tonight, dragging
a warm front over southern WI around daybreak. WAA on the
leading edge of the warm advection will drive showers around
dawn and through the morning hours. All of these showers will
be elevated with negligible MUCAPE, so thunder is not expected.
Shower activity will then grow more scattered heading into the
afternoon as the main push of mid level WAA moves
east/northeast, with strong surface WAA on gusty southwest winds
advecting a warm surface airmass in the mid 70s into southern
WI. A cold front is then expected to move through the area
during the mid to late afternoon. Shower and storm coverage and
strength along the front will be highly contingent upon air mass
recovery during the late morning into the mid afternoon. At
this time, CAMs depict just enough instability along the front
(~400 J/kg CAPE) to drive scattered storm development. However,
the skinny nature of the modeled CAPE profiles will limit storm
strength and severity. A few rumbles of thunder are most likely
with activity along the front, while small hail and gusty winds
will remain isolated and only occur with storms that manage to
become well established in Far SE WI before moving over Lake
Michigan.

Following the cold front, sfc CAA will usher in a cooler air
mass for Wednesday. Highs will be in the low to mid 60s amid
breezy northwest winds. Light frost may occur Wednesday night
into Thursday.

CMiller

&&

.LONG TERM...
Issued 1144 PM CDT Mon May 11 2026

Thursday through Tuesday:

A gradual warming trend will take hold on Thursday as upper
level ridging from the Plains leans east into the Great Lakes
region. Highs are projected to rise into the 80s on Saturday.
The warming will be spurred on by multiple waves of WAA, most
notably Thursday night into Friday, then Saturday into Sunday.
With these waves of WAA, expected shower and storm chances and
modest increases in humidity. Beyond, models vary a bit
regarding how showers and storms will evolve along a passing
cold front on Sunday and how much rain will linger into Monday,
with the ECMWF favoring a drier solution, while the GFS favors
storms Sunday night and lingering showers Monday. In either
case, warmth sticks around for the end of the extended period.

CMiller

&&

.AVIATION...
Issued 1104 PM CDT Mon May 11 2026

Expect continuing VFR overnight with light to moderate
southeast winds. Winds are expected to increase from west to
east around dawn tomorrow and become gusty between 25 to 30
knots, with some potential gusts to 35 knots for KFLD and KSBM.

Rain is also expected to move in around daybreak, though
ceilings will remain VFR. More redevelopment may occur over
southeast Wisconsin in a line from KSBM to KJVL late in the
afternoon. This development will feature better thunder chances
and some of the strongest storms may have gusty winds and small
hail, though widespread severe weather is not expected.

CMiller

&&

.MARINE...
Issued 1051 AM CDT Mon May 11 2026

High pressure will continue to shift east tonight. Light and
variable winds will become south-southeasterly by dawn Tuesday,
with gusty winds developing over the lake quickly through the
morning hours as low pressure approaches from the northwest.
Forecast models suggest that despite a near surface temperature
inversion over the lake, showers over the lake will mix down
gales from the late morning through the mid afternoon. A Gale
Warning has been issued for this time period, over roughly the
middle third of the lake. Gusty winds then ease a bit during the
early evening hours as a cold front passes and winds become
northwesterly. Gusty northwest winds then return Wednesday
morning in the cold advection regime behind the cold front.

North to northwest winds then ease Wednesday night into Thursday
as high pressure moves over Lake Michigan.

Locally, a Small Craft Advisory is in effect Tuesday morning
into Wednesday afternoon for lingering southerly and then
northwesterly gusty winds. A few gale force gusts can't be ruled
out north of Port Washington Tuesday late morning into the mid
afternoon.

CMiller

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...None.
LM...Gale Warning...LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-
     LMZ671-LMZ868-LMZ870-LMZ872...9 AM Tuesday to 5 PM
     Tuesday.

     Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646...9 AM
     Tuesday to 4 PM Wednesday.

&&

$$

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