textproduct: Milwaukee/Sullivan

KEY MESSAGES

- Patchy dense fog in southeast and east central WI will gradually dissipate through mid morning. Marine Dense Fog will diminish from south to north today.

- A High Swim Risk is in effect from mid afternoon through late tonight. High waves and dangerous currents will be likely, and swimming is not advised at Sheboygan and Ozaukee beaches.

- Multiple rounds of storms are expected today and Thursday. Severe thunderstorms are likely at times. An Enhanced Risk for Severe Weather exists both Wednesday and Thursday.

- Warm and humid conditions expected today and Thursday.

UPDATE

Issued 611 AM CDT Wed Jun 10 2026

The early morning storms did not materialize. We only had a thin stripe of mid-level clouds track through southern WI with the warm front.

The fog developed, though. The Dense Fog Advisory for eastern counties is in effect until 7 AM. We will watch for the need for any local extensions. Webcams are showing improvement and some of what we are seeing on satellite is actually stratus.

The shortwave that we are watching to bring our midday-afternoon round of thunderstorms is currently in northeast Kansas. Since we did not have convection this morning, our environment will be primed for severe storms, likely with over 3000 j/kg of CAPE and 30 kt of bulk shear. This will plenty of energy for storms to develop and be sustained from northeast IA into south central WI. Wind and hail are the highest risks. Tornado cannot be ruled out due to 25kt 0-3km shear vectors, but overall 0-3km helicity is not very high. The morning clouds may hinder some of our instability in the east, so wind would be the main concern there.

If there is any area that does not get the midday-afternoon storms, the environment will be better-primed for the late afternoon-evening storms.

Cronce

SHORT TERM

Issued 110 AM CDT Wed Jun 10 2026

Today through Thursday:

Areas of fog are expected in the east overnight into early today given the high dewpoints and relatively chilly waters of Lake Michigan. A Dense Fog Advisory may be needed.

Showers keep trying to form tonight just to the west and southwest as an area of warm advection aloft and higher precipitable water advect into the area. There are still a couple models that try to pop a few storms as this airmass moves in. Plenty of elevated instability tonight along with modest shear and steep mid-level lapse rates would lead to a potential for large hail if storms do fire.

Still watching the potential for a round of thunderstorms after daybreak this morning. The activity over Iowa and into the Dakotas early is expected to largely lift northeast through the top of the upper ridge, staying more closely tied to the shortwave. These storms could clip the northern forecast area roughly between 7 am and 11 am, though latest short term models continue to largely keep this activity to the north.

The main concern for storms today seems to be trending towards the afternoon hours. Latest guidance has latched onto a wave and vort max exiting the OK/TX panhandle area. Any morning storms and associated clouds should largely be out of the area for a decent recovery period late morning into early afternoon. Plenty of instability is expected to go along with modest shear, so severe storms will be possible as the forcing moves into southern Wisconsin. The storms could form into a line relatively quickly, with damaging winds the primary concern. Large hail would also be possible, especially as the activity is getting going. 0-3 km shear isn't particularly strong (25-30 kt), but looks largely perpendicular to the expected line of storms, so a QLCS tornado or two is also possible.

The main round of storms is currently expected to exit the east by 6 pm, while the main trough will swing through during the mid to late evening. This will keep the door open for storms through the evening, though the severe potential would likely be somewhat less if the afternoon round of storms rolls through as expected.

Given the multiple rounds of storms and clouds likely today, not expecting enough sunshine to push heat indices up towards 100 degrees as previously thought possible. While it will be quite warm and humid, widespread Heat Advisory conditions are not anticipated.

There should be a lull in storms tonight into early Thursday between shortwaves. The trough Thursday is expected to be stronger, with an associated surface low and cold front also swing through by mid-evening. The timing of this system is such that there should be plenty of time to destabilize during the day before the stronger forcing moves through. Models are hinting at some warm air advection aloft lifting through by late morning which could muddy things up a little. Overall though, shear and instability should be plenty as this system pushes through for another round of potentially severe storms in the afternoon and early evening. Models continue to suggest that the south half of the forecast area would have the best chance for severe storms based on instability fields, though things have shifted a bit northward compared to 24 hours ago. Given current expected timing, storms should wind down by mid-evening, with a drier airmass moving in overnight behind the cold front.

DDV

LONG TERM

Issued 110 AM CDT Wed Jun 10 2026

Friday through Tuesday:

Dry weather is expected Friday behind the departed low and front, with high temps back towards normal values. Dewpoints will be lower as well, likely settling into the 50s most places.

It is still looking like a shortwave and cold front will drop through the area later Saturday into Saturday night, bring shower/storm chances back to southern Wisconsin. Temps should warm to at least 80 ahead of the front during the day Saturday, with dewpoints creeping back up into the low 60s. Seeing enough shear and instability in the 00Z models to think that a few strong to severe storms will be possible as this system moves through.

Mainly dry weather and cooler conditions are then expected Sunday and Monday as high pressure moves in behind the departing system. Could see shower/storm chances return Tuesday as a shortwave moves through the region.

DDV

AVIATION

Issued 611 AM CDT Wed Jun 10 2026

The patchy dense fog will continue to diminish through mid morning as southerly winds develop. Once the marine-influenced low clouds dissipate, expect VFR until storms roll into south central WI by early afternoon. The storms should quickly evolve into a line and sweep across southern WI this afternoon. Additional storms are expected from late afternoon through late evening. Any storms today could produce large hail, damaging winds and tornadoes.

A pocket of MVFR ceilings will be possible in central and portions of southern WI tonight. Patchy fog will be possible as well.

Cronce

MARINE

Issued 611 AM CDT Wed Jun 10 2026

Marine dense fog advisory in effect across the whole lake until mid- morning, but I am going to extend it in the north.

Generally light northerly winds will continue for the north half until the warm front lifts through the lake by late morning and flips winds around to southerly and southeasterly. Winds will then remain southerly through Wednesday as low pressure approaches from the northern plains. The winds may become moderately breezy late Wednesday afternoon into the evening. Thunderstorms are expected over the lake at times on Wednesday, with some strong storms favored Wednesday afternoon and night.

Winds come around to southwesterly Wednesday night into Thursday, with winds then returning to southeasterly ahead of an approaching cold front on Thursday, with additional storms possible.

Winds will become westerly and breezy behind the front on Friday as low pressure sits near Hudson Bay and high pressure builds into the mid Mississippi River Valley.

Cronce

MKX WATCHES/WARNINGS/ADVISORIES

WI...Dense Fog Advisory...WIZ052-WIZ059-WIZ060-WIZ065-WIZ066-WIZ071- WIZ072 until 7 AM Wednesday.

Beach Hazards Statement...WIZ052-WIZ060...4 PM Wednesday to 4 AM Thursday.

LM...Dense Fog Advisory...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563- LMZ565-LMZ567-LMZ643-LMZ644-LMZ645-LMZ646-LMZ669-LMZ671- LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874- LMZ876-LMZ878 until 10 AM Wednesday.

Small Craft Advisory...LMZ643-LMZ644...4 PM Wednesday to 1 AM Thursday.