textproduct: Milwaukee/Sullivan

KEY MESSAGES

- A mix of light rain and light snow is forecast overnight (30 to 60 percent chances) in south central Wisconsin, with some light freezing rain mixed in over areas mainly northwest of Madison. Any light ice accumulation would be on elevated surfaces. - Milder temperatures return on Wednesday, with widespread showers (around 85 percent) forecast late Wednesday afternoon during the passage of a cold front.

- Another round of showers with a few storms (40 to 65 percent) should occur Thursday night, followed by an active weather pattern of warmer temperatures and more showers and storms Sunday into Monday.

UPDATE

Issued 521 AM CDT Tue Apr 7 2026

Skies are clear across Wisconsin early this morning and the northerly winds continue to diminish. It is cold, with temperatures in the lower to mid 20s. Locations toward central WI will bottom out closer to 20, with a few pockets of upper teens possible in low-lying areas.

Sunshine will prevail today, but temperatures will only rebound into the mid/upper 30s near Lake Michigan to mid 40s well inland. Thankfully, the winds will be light.

Precipitation will spread into southern WI from the southwest around midnight tonight as the nose of the low level jet pushes into southern MN and southwest WI. The better LLJ forcing will be over MN, but a weak mid level shortwave will be tracking over southern WI during this time.

Model forecast profiles show dry air in the low levels, especially over southeast WI. This will keep the precip amounts light, and potentially only sprinkles in the southeast. As for the temperature profiles, models have a range of solutions, but generally indicate snow transitioning to freezing rain/sleet (min temps in the mid 20s to lower 30s) and then quickly over to light rain as the temps warm. So we have a brief period where a wintry mix is possible, mainly north of Madison to West Bend where we could see a light glaze on elevated surfaces during the overnight hours. Pavement temperatures should inhibit travel impacts, but bridges and overpasses could be susceptible for a few hours before the temperatures warm above freezing. Elsewhere, while a brief wintry mix is possible, it should be too light to accumulate in any way.

Cronce

SHORT TERM

Issued 1221 AM CDT Tue Apr 7 2026

Overnight through Tuesday night:

Some middle to high clouds may linger in southern portions of the area overnight. Otherwise, mostly clear skies are expected to linger overnight into most of Tuesday. Any lingering gusty winds should gradually weaken overnight and become northeast to east on Tuesday, as high pressure moves across the region. Lows tonight should drop into the upper teens to lower 20s, with highs Tuesday in the lower 40s well inland and middle 30s closer to the lakeshore.

Winds will shift southeast Tuesday night and gradually increase, with warm air advection at 850 mb developing with a south southwesterly low level jet. The best moisture transport and upward motion should be just west of the area, but enough of this should move through south central Wisconsin to bring 30 to 60 percent chances for precipitation there.

Forecast soundings and wet bulb temperatures suggest a transition from light snow to a wintry mix of light snow, light freezing rain and light rain to mainly light rain by Wednesday morning for areas northwest of Madison. Areas to the south and east of there should be more of a light snow to light rain transition, as temperatures warm up after 06Z Wednesday. The far southeast parts of the area may not see much precipitation, as the air column there is drier.

There remains a risk for light ice accumulations northwest of Madison later Tuesday night, perhaps a light glazing mainly on elevated surfaces. Will continue to message this potential. It should transition to all light rain by 12Z Wednesday.

Wood

LONG TERM

Issued 1221 AM CDT Tue Apr 7 2026

Wednesday through Sunday:

As low pressure tracks eastward across southern Canada mid week, gusty southerly winds and a warming trend arrive, with Wednesday's high temps soaring into the low to mid 60s inland, some 50s along the shoreline with the cooling influence of the lake. Rain chances (30-50%) linger north of a Monroe to West Bend line through the day Wednesday with all of the WAA aloft, with a cold front tracking west to east through the region Wednesday evening/night and boosting rain chances to ~75% area- wide. Likely a widespread wetting rainfall.

A light southwest to west breeze continues behind that cold front Thursday, though temperatures remain around 60 to the mid 60s with the warmth likely spreading to the shoreline. A surface trough develops south of the region, with only ~20% chances for associated rain showers to reach southern Wisconsin Thursday afternoon.

The trough and associated rainfall wobble north Thursday evening/night delivering 40-65% rain chances (highest further south and east in our region) before high pressure builds into the upper Great Lakes region and forces the baroclinic zone clear of our region. Hence, dry weather likely for much of Friday and into the daytime hours of Saturday. Inland highs in the 50s to around 60 expected, with east flow off the lake leading to cooler shoreline temps.

A more organized low pressure system is then expected to develop over the Rockies and track eastward over the northern Great Plains this weekend, likely dragging a potent warm sector into Wisconsin Sunday/Monday. Ensemble temperature IQRs indicate relatively high confidence for highs in the 70s these two days, possibly even the low 80s. The presence of this warm sector brings with it a chance for showers and thunderstorms.

Sheppard

AVIATION

Issued 521 AM CDT Tue Apr 7 2026

Clear skies and light winds are expected through the day. Look for winds to become southerly this evening as mid level clouds begin to spread in from the west. A period of snow/freezing rain/sleet is likely during the overnight hours, mainly north of Madison to West Bend between 1 and 4 AM (08-11Z). A brief and very light wintry mix is possible south of there, but dry air in the low levels will keep it lighter than toward central WI. Ceilings and visibility are expected to remain VFR during the precip, but conditions may briefly become MVFR.

Cronce

MARINE

Issued 521 AM CDT Tue Apr 7 2026

The Small Craft Advisory will be allowed to expire at 7 AM as winds and waves diminish. Another Small Craft Advisory will be needed for increasing southerly winds on Wednesday. A few gale force gusts are possible.

Gusty northerly winds will decrease through the morning as high pressure around 30.6 inches moves across central Lake Michigan into the early afternoon. Low pressure around 29.5 inches will then track along the Northern Plains/Canadian border tonight and Wednesday, then track north of Lake Superior Wednesday night into Thursday morning. This will result in breezy southerly winds over Lake Michigan on Wednesday with gale force gusts up to 40 kt. A Gale Watch is in effect for the northern three quarters of the lake.

Much weaker winds will then take hold by Thursday afternoon into Friday as high pressure around 30.4 inches slowly moves through the region.

Cronce

MKX WATCHES/WARNINGS/ADVISORIES

WI...None. LM...Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646 until 7 AM Tuesday.

Gale Watch...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567- LMZ669-LMZ671-LMZ673-LMZ868-LMZ870-LMZ872-LMZ874...7 AM Wednesday to 4 AM Thursday.