textproduct: Milwaukee/Sullivan

KEY MESSAGES

- A Winter Weather Advisory remains in effect through this morning. Snow showers will come to an end early this morning, with little additional accumulation. Gusty northwest winds will lead to areas of blowing and drifting snow and reduced visibility.

- A Cold Weather Advisory remains in effect through this morning across all of southern Wisconsin. Bitter cold wind chills of 23 to 30 below zero are expected during this period. Wind chills in the teens below zero are then expected this afternoon into Tuesday morning. - A Gale Warning remains in effect for all of Lake Michigan through late afternoon. A Heavy Freezing Spray Warning remains in effect as well through Tuesday morning.

- Accumulating snow is expected (70 to 90 percent chances) Tuesday night, with chances (20 to 40 percent) lingering Wednesday into Wednesday evening. Several inches are possible Tuesday night. - Bitter cold temperatures and wind chills are possible again Thursday night/Friday morning into the weekend.

SHORT TERM

Issued 441 AM CST Mon Jan 19 2026

Today through Tuesday:

The Winter Weather Advisory remains in effect through this morning, mainly for blowing snow reducing visibility. There are some stubborn lingering snow showers and flurries across eastern portions of the area, with some differential CVA moving through the region. This activity should gradually move out of the area by sunrise, with little to no additional accumulations expected.

The main issue will be the gusty west northwest winds bringing blowing snow into this morning. Gusts of 30 to 40 MPH should occur within the strongest cold air advection, and help blow around the fluffy and powdery snow that has recently fallen. Some airport observations have seen 1 to 3 mile visibility reductions from the blowing snow at times so far, and this should continue to occur into this morning. Winds should start to ease somewhat this afternoon into tonight, with the blowing snow risk diminishing.

The Cold Weather Advisory will continue through this morning as well, with wind chills of 23 below to 30 below zero expected at times. The better chances for the near 30 below zero readings would be in south central Wisconsin. Wind chills will be in the teens below zero this afternoon into Tuesday morning, with some areas in the northern parts of the area near 20 below zero at times. For now, no additional Cold Weather Advisories are planned. Highs today may reach into the zero to 5 above zero range, with lows tonight in the 5 below to 1 below zero range.

Clouds should gradually scatter out today from west to east, with some additional clouds moving into the area this evening for a time before moving out later tonight. High pressure passing by to the south of the region later tonight into Tuesday should bring dry conditions to the area, with temperatures rising into the teens above zero Tuesday.

Wood

LONG TERM

Issued 441 AM CST Mon Jan 19 2026

Tuesday night through Sunday:

Synopsis: Mean upper troughing will continue to linger from the Hudson Bay into the western Great Lakes through the duration of the long term period. Given the persistent synoptic pattern, southern Wisconsin will remain favorably positioned for impacts from clipper systems, with attendant surface cold frontal passages bringing additional bouts of very cold temperatures and wind chills.

Tuesday evening through Wednesday is currently favored for the most widespread snow potential across the area, when a pair of clipper systems will move through the western Great Lakes. Signals in deterministic and ensemble guidance continue to point toward some accumulation potential. Low level winds will turn northwesterly behind the Tuesday evening-Wednesday system, with chilly temperatures and wind chills settling in for the Wednesday night through Thursday time frame.

Signals for another clipper system are evident during the Thursday night through Friday morning time period, though uncertainty remains regarding wintry precipitation potential in southern Wisconsin.

Of greater confidence, however, is that another pull of Arctic air will sag into the western Great Lakes with the affiliated clipper system during the Friday morning-Sunday time period. Additional very chilly temperatures and wind chills are thus anticipated from the end of the work week through next weekend.

Tuesday Evening through Wednesday: Deterministic & ensemble guidance continues to point toward the best precip chances of the period (about 50 to 70 percent) during this time frame. Precipitation will occur as all snow, as a pair of clipper systems move across the western Great Lakes. The first is forecast to move overhead Tuesday evening into Wednesday morning, with steady snows focusing along bands of warm advection and frontogenesis in the 925-700 mb layer.

A brief lull may follow through part of the day Wednesday, with additional light snow showers filling in later in the day as the second clipper moves in and drags a cold front through southern Wisconsin. Deterministic and ensemble guidance continues to suggest accumulation potential, with the majority of said accumulation occurring with the first of the two systems Tuesday evening through early Wednesday morning.

Available guidance is showing better agreement regarding the placement of forcing mechanisms and steadiest snows Tuesday evening into Wednesday morning, with a loose consensus beginning to point to the southern half of the CWA as the favored location for better lift and steady snow potential.

Nevertheless, some north-south spread does remain in the guidance suite, so trends will be monitored. Probabilistic snow forecasts indicate medium-high (about 40 to 80 percent or greater) potential of at least an inch areawide, with signals supportive of generally 2 to 4 inch totals where warm advection and frontogenesis ultimately set up.

Will continue to provide additional information as more model data becomes available over the next 12 to 24 hours. Though lighter relative to the first round, could see some areas of blowing snow with the second round of snow later Wednesday, as winds pick up behind the cold front. Keep up with the forecast if planning to be on the roads Tuesday evening through Wednesday.

Wednesday Night through Thursday: The first of two reinforcing pulls of Arctic air remains on track to move across southern Wisconsin. Continue to maintain wind chill forecasts from the NBM, which indicate widespread wind chills in the -10 to -15 range late Wednesday night through the first half of Thursday morning. These values are well-aligned with current probabilistic wind chill forecasts, which show low (<20%) potential of reaching Cold Weather Advisory criteria. Will nevertheless continue to monitor for colder trends in coming forecasts.

Thursday Evening through Sunday: Another clipper system is progged to cross the western Great Lakes during the Thursday evening-Friday time frame. The disturbance could bring additional potential for light snow, though uncertainties pertaining to system track and potential interactions between multiple areas of forcing make it too early to confidently offer additional details.

What is more certain is that another area of Arctic air will sag into the western Great Lakes along and behind the system, with a prolonged period of bitterly cold temps and wind chills anticipated from Friday morning through Sunday. Coldest overall conditions will be during the overnight periods, when probabilistic guidance indicates appreciable (40 percent or greater in some spots) potential of reaching at least Cold Weather Advisory thresholds. Will thus be monitoring for possible cold weather headlines as this part of the period draws closer.

Quigley

AVIATION

Issued 441 AM CST Mon Jan 19 2026

There are some stubborn lingering snow showers and flurries across eastern portions of the area. This activity should gradually move out of the area by sunrise, with little additional accumulations expected. There may be 2 to 5 mile visibility at times within these brief snow showers.

The main issue will be the gusty west northwest winds bringing blowing snow into this morning. Gusts of 28 to 34 knots should occur and help blow around the fluffy and powdery snow that has recently fallen. Some airport observations have seen 1 to 3 mile visibility reductions from the blowing snow at times so far, and this should continue to occur into this morning. Winds should start to ease somewhat this afternoon into tonight, with the blowing snow risk diminishing.

Ceilings have been tricky, with mainly 1500 to 2500 foot ceilings with some VFR level ceilings and some clearing areas mixed in. The ceilings should gradually scatter out today from west to east, with some additional ceilings moving into the area this evening for a time, before moving out later tonight.

High pressure passing by to the south of the region later tonight into Tuesday should bring dry conditions to the area.

Wood

MARINE

Issued 441 AM CST Mon Jan 19 2026

Low pressure around 29.5 inches will move from the eastern Upper Peninsula of Michigan to eastern Ontario today. An Arctic cold front will move east of the lake into this morning, with rapidly increasing west northwest winds behind it. Widespread gales are then expected through today, with a Gale Warning in effect until 6 PM CST this evening for all of Lake Michigan.

A Gale Warning remains in effect for the nearshore waters of Lake Michigan until noon CST today, for west northwest gales. A Small Craft Advisory is then in effect after the Gale Warning expires until late tonight, for lingering gusty west northwest winds. Some freezing spray may occur, mainly toward the open waters.

Winds will weaken somewhat this evening into early Tuesday morning, as high pressure around 30.4 inches remains well south of the region. Winds will shift southwesterly Tuesday afternoon, as the high moves into Tennessee. Elevated waves and arriving Arctic air will lead to areas of heavy freezing spray through Tuesday morning. A Heavy Freezing Spray Warning remains in effect until 12 PM CST Tuesday for all of Lake Michigan.

West to southwest winds will continue into Wednesday, as low pressure around 29.6 inches passes across the lake. Winds will increase further and shift west to northwest Wednesday night, as another Arctic cold front crosses Lake Michigan. A few gale force gusts may occur. Arriving Arctic air and elevated wave heights will support additional periods of moderate to potentially heavy freezing spray Wednesday night into Thursday.

Winds will turn north to northwest Friday, as strong high pressure around 30.8 inches builds into the northern Great Plains.

Wood

MKX WATCHES/WARNINGS/ADVISORIES

WI...Winter Weather Advisory...WIZ046-WIZ047-WIZ051-WIZ052-WIZ056- WIZ057-WIZ058-WIZ059-WIZ060-WIZ062-WIZ063-WIZ064-WIZ065- WIZ066-WIZ067-WIZ068-WIZ069-WIZ070-WIZ071-WIZ072 until noon Monday.

Cold Weather Advisory...WIZ046-WIZ047-WIZ051-WIZ052-WIZ056- WIZ057-WIZ058-WIZ059-WIZ060-WIZ062-WIZ063-WIZ064-WIZ065- WIZ066-WIZ067-WIZ068-WIZ069-WIZ070-WIZ071-WIZ072 until noon Monday.

LM...Gale Warning...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563- LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779- LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 until 6 PM Monday.

Heavy Freezing Spray Warning...LMZ080-LMZ261-LMZ362-LMZ364- LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675- LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 until noon Tuesday.

Gale Warning...LMZ643-LMZ644-LMZ645-LMZ646 until noon Monday.

Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646...noon Monday to 3 AM Tuesday.