textproduct: Milwaukee/Sullivan

KEY MESSAGES

- Wind chills will fall into the teens below zero for several hours overnight.

- Above average temperatures develop Tuesday afternoon through Thursday, with highs in the middle to upper 30s.

- The next chances for precipitation (50 to 60 percent) develop late Wednesday night into Thursday morning. With temperatures near to above freezing, much of this precipitation is expected to be rain. A transition to snow is possible overnight.

UPDATE

Issued 945 PM CST Sun Dec 14 2025

Middle to high clouds will continue to push southeast through the area overnight into Monday, as warm air advection continues to develop. There are mainly small chances (around 20 to 30 percent) for light snow showers or flurries to move through northeast parts of the area toward 12Z Monday, as a sheared 500 mb vorticity maximum with some differential CVA shifts southeast through the region.

Southwest winds will become gusty overnight into Monday, as the pressure gradient tightens and mixing in the low levels develops. Temperatures should start to rise overnight and rise into the lower to middle 20s for highs on Monday. Wind chills will still be in the teens below zero into the overnight hours and early Monday, and in the single digits below zero through Monday morning.

Wood

SHORT TERM

Issued 259 PM CST Sun Dec 14 2025

Tonight through Monday night:

High pressure building across the region will lead to light and variable winds this evening into tonight before shifting to become southwesterly late tonight as high pressure slides off to the east and low pressure pushes into the northern Plains. Gusts between 20 and 30 mph will develop overnight as high pressure exits, bringing wind chills in the negative teens once again. However, these gusty southwest winds will also usher in a much warmer airmass, so wind chills are expected to improve overnight as temperatures warm even before sunrise. High temperatures in the mid-20s are expected on Monday, with perhaps a few snow flurries in central Wisconsin in the morning hours as low pressure weakens and swings northeastward into Quebec.

Monday night, winds diminish, but generally remain southerly. Expect lows in the low teens to upper single digits, with the highest temperatures along Lake Michigan.

MH

LONG TERM

Issued 259 PM CST Sun Dec 14 2025

Tuesday through Sunday:

Quite the pattern change expected for the Upper Midwest this week. Overall will see a gradually warming trend Tuesday through Thursday with prevailing southerly flow and WAA. Temps will warm into the mid to upper 30s each afternoon. There is even a 30-40% chance based off the NBM to see high temps crack into the 40s on Wednesday and 40-60% chance on Thursday for southeasterly WI.

While southern WI enjoys this warm up, will also see a fairly progressive pattern with an upper-level ridged building across the region on Tuesday followed by a shortwave trough digging in Tuesday night into Wednesday. Overall, will see the pressure gradient tighten up and become breezy as a cold front swings through overnight Tuesday, but generally expecting a dry front passage. Will see high pressure/ridge build back in quickly behind the front for Wednesday with low-level WAA spreading across the region Wednesday afternoon into Thursday.

Thursday looks to be the most active period of the extended with an upper-level trough digging across the Northern Plains and into the Upper Great Lakes through the day. Models continues to bounce between solutions and track of the surface low with this system. Latest 12z mid-range models generally agree on the the deepening low to track across northern MN into the Lake Superior region through the day Thursday. This will keep southern WI in the warm sector of the system and with a slug of Pacific moisture combining with Gulf moisture will result in increase precipitation chances (40- 70%). Still some questions on the precip type as it depends on the low track and timing, but could see rain during daytime hours ahead of the cold front, and then some wintry mix into Thursday night and transitions to snow on the backside/CAA side of the passing system. Nevertheless, will need to keep an eye on trends over the next few days with this end of week system.

Otherwise, things look to cool down for the end of the week before warming back up into the weekend with another system progged to trek across region bringing additional precip chances and return of colder airmass for the latter half of the weekend.

Wagner

AVIATION

Issued 945 PM CST Sun Dec 14 2025

Middle to high clouds will continue to push southeast through the area overnight into Monday. There are mainly small chances (around 20 to 30 percent) for light snow showers or flurries to move through northeast parts of the area including the Sheboygan terminal toward 12Z Monday.

Southwest winds will become gusty overnight into Monday, as mixing in the low levels develops. Low level wind shear conditions are expected overnight into Monday morning, with southwest winds around 45 knots at 2000 feet AGL. These winds will gradually weaken Monday evening and become more southerly later Monday night. Middle to high clouds Monday night may lower but may remain VFR category.

Wood

MARINE

Issued 945 PM CST Sun Dec 14 2025

Strong southwest winds are expected to develop later tonight into Monday, with strong high pressure around 30.7 inches well to the southeast and a frontal boundary moving into Lake Superior. A Gale Warning is in effect for this time frame across Lake Michigan.

A Small Craft Advisory is in effect for the nearshore waters of Lake Michigan later tonight into Monday afternoon.

A weak cold front will shift winds to the west Monday afternoon and evening. Low pressure around 29.2 inches then develops in southern Alberta and progresses eastward across southern Canada, bringing gusty southwest winds and gale potential to the northern half of the lake Tuesday afternoon and Tuesday night. A Small Craft Advisory will be needed for the nearshore waters.

Winds diminish and become westerly to northwesterly late Tuesday night into Wednesday, as low pressure exits the region. Another system is expected on Thursday, bringing gusty southwest winds, with gusty northwest winds Thursday night into Friday. Gales may be possible at times during these periods, with Small Craft Advisory conditions for the nearshore waters.

MH/Wood

MKX WATCHES/WARNINGS/ADVISORIES

WI...None. LM...Gale Warning...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563- LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779- LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 AM Monday to noon Monday.

Small Craft Advisory...LMZ645-LMZ646...2 AM Monday to 3 PM Monday.

Small Craft Advisory...LMZ643-LMZ644...2 AM Monday to noon Monday.