textproduct: Milwaukee/Sullivan

KEY MESSAGES

- Light snow through this evening with accumulations between 0.5 and 1.5 inches.

- Another light snow event early Wednesday morning with amounts of an inch or less.

- Much colder Wednesday night through Thursday night.

- Several chances for light snow late in the week, though with low confidence on details.

SHORT TERM

Issued 353 PM CST Mon Dec 1 2025

Tonight:

Snow is spreading into southern Wisconsin this afternoon. This is due to a mid level shortwave trough making its way across the region. Once the low levels saturate, visibilities are dropping down to 1 to 2 miles. This saturation is filling in from west to east. Despite the healthy layer (up to 5000 ft) of clouds within the dendritic growth zone, the overall lift (omega) is weak. Therefore, still expecting snowfall totals just shy of an inch north of I-94 from Madison to Milwaukee and US-14 west of Madison, to up to 1.5 to 2 inches near the WI/IL border.

We are seeing an elongated area, or axis, where snow is beginning earlier than surrounding areas, primarily from Dubuque to Madison and Oshkosh, and now over to Sheboygan. There is weak frontogenesis ongoing at the 600mb level and also warm air advection at 700mb. This led to mid clouds producing snow aloft to help saturate the lower levels quicker than surrounding areas. The deeper moisture is translating into southeast WI now, and it is beginning to snow in Milwaukee.

The steadier snow is expected to exit southeast WI from west to east from 9 pm to 1 am. However, upstream obs in the Twin Cities area are showing light snow coincident with the lagging edge of the mid level shortwave trough. This feature should exit eastern WI between midnight and 3 am. We will keep an eye on trends this evening and potentially extend the light snow/flurry chances into the overnight hours. This would not affect the overall snowfall totals. Winds will be light throughout this snowfall event. Lows will be in the lower teens tonight, although single digits will be possible northwest of Madison if any clearing occurs.

Tuesday through Wednesday:

The surface high pressure ridge will be passing by to our south on Tuesday. With a weak low pressure trough crossing the northern Plains, expect steady southerly winds across southern WI. We should manage to see breaks in the clouds at times. Highs are expected to top out in the lower to mid 20s, similar to today.

Tuesday night, clouds and moisture will return to southern WI ahead of a strengthening surface trough and a weak shortwave trough. Look for increasing southerly winds overnight. Lows will be in the mid to upper teens, but those lows will occur in the evening and then gradually rise toward morning.

Light snow along the surface trough will likely begin in central WI prior to daybreak Wednesday and then slide across the rest of srn WI through midday. This is looking like a half to one inch light snow event with this clipper. High temperatures will occur while it is snowing, in the lower 30s.

Gusty northwest winds will develop behind the cold front Wednesday afternoon and evening. Arctic air will bring low temperatures down to the single digits below zero for all of southern WI except the lakeshore counties. While this is much colder than normal for early December, the lows are not quite in record territory. Wind chill values early Thu morning will be in the 17 to 20 below range which is approaching Wind Chill Advisory levels.

Cronce

LONG TERM

Issued 353 PM CST Mon Dec 1 2025

Thursday through Monday:

High pressure and the arctic air should allow for sunshine on Thursday and highs around 10 to 15. The next clipper system should arrive Friday afternoon but this looks like it could just be flurries.

A weak warm air advection precip feature with a shortwave will slide across the Midwest on Saturday afternoon or night. This snow may clip southern WI.

Cronce

AVIATION

Issued 353 PM CST Mon Dec 1 2025

Visibilities dropped to the 1 to 3 mile range quickly as the light snow spread in from west to east this afternoon. Ceilings will also fall quickly to MVFR with pockets of IFR possible toward southwest WI. The snow will wind down between 03Z and 06Z, although flurries may linger into the overnight hours. Dry weather is expected Tuesday and Tuesday evening.

Snow totals of around an inch are possible through the I-94 corridor, with lesser amounts toward the north and totals pushing 2 inches towards the WI/IL border. The snow will likely be a drier snow given temps in the low to mid 20s, with snow to liquid ratios 14-16 to 1. Winds should remain on the light side through during the snow event. Visibilites will likely improve for overnight and Tuesday, with MVFR ceilings possibly hanging around much of the day.

DDV/Cronce

MARINE

Issued 353 PM CST Mon Dec 1 2025

Steady southerly winds will become west to southwest late tonight and Tuesday as an area of high pressure moves through the Ohio Valley.

A strong cold front along a low pressure trough will cross Lake Michigan Wednesday. Gusty southwest winds are expected ahead of this front early Wednesday morning, with gusty northwest winds behind it Wednesday afternoon and night. Winds are expected to remain just below gale force, although a few gale force gusts look possible. Very cold air with this system will result in a risk for freezing spray Wednesday night and Thursday.

Light winds are expected Thursday with the influence of high pressure over Illinois and Indiana. Another period of elevated southwest winds will occur Thursday night into Friday as another low pressure trough crosses the Upper Great Lakes.

Cronce

MKX WATCHES/WARNINGS/ADVISORIES

WI...None. LM...None.