textproduct: Milwaukee/Sullivan

KEY MESSAGES

- Dry weather under high pressure expected through the weekend and into next week. Fire weather concerns may increase into early next week.

UPDATE

Issued 615 AM CDT Fri May 29 2026

Influence from high pressure continues to bring dry and mild pattern to southern WI today with highs climbing into the upper 70s lower 80s for inland areas, while a lake breeze is likely to develop and push inland through the afternoon keeping temps cooler by Lake Michigan. Still expecting to see easterly winds pick up overnight into Saturday with a backdoor cold front like boundary bringing cooler onshore flow for Saturday. Thus looking at highs only in the upper 50s to 60s for lakeshore counties with low to upper 70s west of the Kettle Moraine. Given this pattern with breezy onshore flow, waves are expected to build to around 3 feet for southeastern WI beaches resulting in moderate swim risk for Saturday. While confident in moderate swim risk, could see waves build to around 4-5 feet if winds persist longer and increase a bit more. So will need to monitor for a potential upgrade if this trend materializes.

Wagner

SHORT TERM

Issued 1142 PM CDT Thu May 28 2026

Tonight through Friday night:

Light and variable winds are expected through much of the day Friday as high pressure settles in across Wisconsin and Michigan. Temperatures will drop into the mid 40s to upper 50s tonight under clear skies and could lead to patchy fog development mainly for low lying areas north and west of Madison. The main limiting factor for fog development is the dewpoints/moisture. Dewpoints have slowly across far southern, east central and southeastern Wisconsin, which is now in the upper 30s. Dewpoints are slightly higher further west in the mid to upper 40s. Long and short here, patchy fog is possible and it will burn off shortly after sunrise.

Otherwise dry, quiet, and warm Friday. Given the light and variable winds, a lake breeze will likely move inland which will keep conditions cooler along the lake. Generally can expect temperatures in the low 80s from the Kettle Moraine west and highs in the mid 60s to upper 70s for areas east of there.

Friday night will be another benign weather night for southern Wisconsin. Not anticipating fog to develop with the potential for some upper level clouds, lower dewpoints, and overnight lows in the low to mid 50s. So slightly warmer and dryer means no fog :).

Patterson

LONG TERM

Issued 1142 PM CDT Thu May 28 2026

Saturday through Wednesday:

A largely quite and uneventful extended forecast for southern Wisconsin. Wisconsin is going to be trapped under a ridge between a strong trough out in the eastern CONUS and another in the central High Plains/Rockies. At the surface, a broad area of high pressure looks to linger across the Great Lakes region through mid weak. The areas of high pressure will predominately descend down from Canada and linger in the region before advecting southeast with time toward the mid Atlantic coast. There are signals for a weak backdoor cold front Saturday night into Sunday and again Monday into early Tuesday. There is a very small chance (around 10%) for showers to develop Monday with the backdoor front, but otherwise the biggest impacts here will be a wind shift and slightly cooler temperatures.

Winds will be light through the extended with highs expected to be in the upper 60s to low 80s through mid week. Generally cooler temperatures expected near the lake with warmer conditions inland. The coolest temperatures along the lake are expected in the hours behind those backdoor cold fronts. Temperature trends look to climb upward Thursday with hints at highs in the upper 80s.

The only concern for the extended will be the potential for some increasing fire weather conditions. With the Hudson Bay highs were looking at a prolonged period of dry conditions on top of an already fairly dry May. The most recent drought monitor has portions of southern Wisconsin as abnormally dry already, which isnt horrible (especially given the wet April we had). Will just have to keep an eye on how well RH's/dewpoints recover overnight and how much mixing we get during the daytime (drying). This will be especially important behind the weak backdoor fronts. Not a critical concern by any means just something to monitor.

Patterson

AVIATION

Issued 615 AM CDT Fri May 29 2026

VFR conditions will prevail through the period with light and variable winds for much of southern WI terminals. Lakeshore terminals are expected to see lake breeze develop and push inland later this morning and afternoon bringing breezy and abrupt easterly wind shift. Winds then become light and variable again behind the lake breeze passage through the evening before a backdoor cold front pushes southward and brings increased easterly winds later Saturday morning and into the afternoon.

Wagner

MARINE

Issued 1142 PM CDT Thu May 28 2026

High pressure around 30.3 inches will remain across the Great Lakes Region now through roughly mid next week. Light and variable winds will be predominately for much of this time. Saturday night into Sunday morning and Monday night into Tuesday there will be a chance for two separate weak cold fronts to pass Lake Michigan. Dry weather and a weak wind shift to northerly is expected behind each front. As the second weak front passes, the dominated high pressure is expected to slide southeast toward the Mid Atlantic which should keep winds north to northeast into Wednesday.

Patterson

MKX WATCHES/WARNINGS/ADVISORIES

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