textproduct: Milwaukee/Sullivan

KEY MESSAGES

- Areas of very light snow or flurries this afternoon and evening, but cannot rule out a brief mix of freezing drizzle at onset of the snow this afternoon.

- An Arctic airmass settles in this weekend with wind chills ranging from -10F to -30F late tonight through Sunday night. - Next week temps return to near normal with daytime temps around or above freezing by midweek.

UPDATE

Issued 1035 AM CST Fri Dec 12 2025

Band of light snow is beginning to move into WI late the morning and push into southern WI early this afternoon. Have seen a few reports upstream in southeast MN/west WI of some mix of freezing drizzle right at the onset of the light snow. May see some slick spots develop with this activity, but will quickly swing through the area this afternoon before turning to all snow. Minor accumulations of a dusting and maybe a slightly more.

Otherwise, the bitter cold advecting in tonight will be the main story this weekend. Have extended the current Cold Weather Advisory through Sunday morning as winds only briefly fall below criteria Saturday afternoon for a few hours. Also have added the southern counties along the WI/IL border into a Cold Weather advisory as well but will not begin until 6 PM CST Saturday and continue through Sunday morning as well. Regardless of the cold weather headlines and timing it continues to look bitter cold tonight and through the weekend with impacts to anyone exposed to these dangerous conditions.

Wagner

SHORT TERM

Issued 450 AM CST Fri Dec 12 2025

Today through Saturday:

The upper trough over Manitoba will amplify as it moves sewd into Ontario today and tonight. Cyclogenesis will ensue north of Lake Superior this afternoon and continue ewd as well. This will drive the arctic front, currently over wrn MN, through srn WI this evening. Areas of very light snow or flurries can be expected with the frontal passage. Brisk nwly winds and very cold temps will drop the wind chill temps to -20 to -25F for Sat AM from Madison to Milwaukee and northward. Thus a Cold Wx Advisory is now in effect.

During the day on Sat, a frontogenetic band of light snow will move across IA and IL, but it could clip far srn WI. 20-40% chances of light snow are forecast near the IL border. High temps only in the single digits above zero are forecast. An upper trough axis will then swing sewd from Canada Sat nt, thereby reinforcing the arctic air. Low temps well below zero for well inland locations are forecast along with wind chill temps of -20 to -29F over all of srn WI. The arctic high around 1045 mb will reach IA by 12Z Sun then move ewd into the Ohio Valley by Sun nt. Swly winds and warm advection will then begin Sun nt but still with cold temps and wind chills hanging on.

Gehring

LONG TERM

Issued 450 AM CST Fri Dec 12 2025

Saturday night through Thursday:

The arctic high pressure weakens and pushes southeast of the region Monday, continuing into the Atlantic Ocean through mid week. Breezy southwest winds (strong WAA) are expected through the first half of next week, likely boosting daytime highs around or slightly above the freezing mark Tuesday, then towards 40 degrees for Wednesday. Strong low pressure tracking eastward across Canada will allow the WAA to continue the pace even as the arctic high dissipates and merges into the Atlantic mid week. Dry weather is looking likely through the first half of the week.

Predictability drops from mid next week onwards, but models do hint at a passing low pressure system, which could be anything from a small clipper system (00z-GFS) to a more dominant synoptic low pressure system (00z-ECMWF). We've left precip chances (30-40%) in the forecast from Wednesday evening onwards to compensate.

Sheppard

AVIATION

Issued 1035 AM CST Fri Dec 12 2025

Band of light snow will swing through southern WI this afternoon and mainly impacting SBM and maybe MSN. Terminal south are looking drier, but may see some light flurries with limited impacts. Overall mainly expecting VFR conditions, but could see lower ceilings build in this evening as the Arctic front pushes through overnight. However drier air and subsidence will help clear ceilings out overnight. Light westerly winds this afternoon will gradually increase this evening into Saturday and turn more northwesterly overnight.

Wagner

MARINE

Issued 450 AM CST Fri Dec 12 2025

Light and variable winds this morning will give way to breezy southwest winds this afternoon as low pressure around 29.7 inches develops north of Lake Superior and moves east through the weekend. The low will sweep an arctic front across Lake Michigan tonight, with a prolonged period of brisk northwest winds and heavy freezing spray for much of the weekend.

High pressure around 30.8 inches will move southeast from the northern Plains and through the western Great Lakes late Sunday. Winds ease later Sunday as the high approaches, but gusty winds may return early next week as the high exits into the Ohio River valley.

Brisk nwly winds has resulted in a Small Craft Advisory from Sheboygan to Winthrop Harbor for this evening through Sun A>

Gehring

MKX WATCHES/WARNINGS/ADVISORIES

WI...Cold Weather Advisory...WIZ046-WIZ047-WIZ051-WIZ052-WIZ056- WIZ057-WIZ058-WIZ059-WIZ060-WIZ063-WIZ064-WIZ065- WIZ066...midnight Saturday to 10 AM Sunday.

Cold Weather Advisory...WIZ062-WIZ067-WIZ068-WIZ069-WIZ070- WIZ071-WIZ072...6 PM Saturday to 10 AM Sunday.

LM...Heavy Freezing Spray Warning...LMZ080-LMZ261-LMZ362-LMZ364- LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675- LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876- LMZ878...midnight Saturday to 9 AM Sunday.

Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646...9 PM Friday to noon Sunday.