textproduct: Milwaukee/Sullivan

KEY MESSAGES

- Increasingly warm and continued low relative humidity days through Thursday. Elevated fire weather conditions are possible Thursday.

- Increasing humidity and thunderstorm chances for late Thursday night through Saturday. A 1 out of 5 (marginal) risk for severe storms is forecast Friday into Friday night, but confidence in potential severe storm timing is low.

UPDATE

Issued 659 PM CDT Wed Jun 3 2026

Lake breeze has made it to the Kettle Moraine this evening, bringing temperatures in the low to mid 70s. Farther inland, temperatures around 80 degrees continue. All temperatures will fall into the mid-50s overnight tonight.

MH

SHORT TERM

Issued 215 PM CDT Wed Jun 3 2026

Tonight through Friday night:

Tonight through most of the day Thursday the upper ridge and corresponding surface high in the eastern US appear likely to hang on keeping us largely dry through then. Thursday will likely reach the mid 80s for highs with fairly low dewpoints and modestly breezy conditions and given the RHs expected to be low in the 25-35% range. Given drying fuels for parts of southern WI elevated fire weather conditions could be expected.

Higher clouds will likely start pushing in later Thursday as a shortwave and weak surface low pressure nudges in from the west. Later Thursday and more specifically Thursday night we should see the forcing measures slide in with increasing chances for showers and weak thunderstorms. CAMs have largely limited much of the overnight potential but closer to daybreak Friday we see some of that activity push in. Larger scale models have the northwest parts of the CWA seeing earlier nighttime activity which is something to watch for but more widespread activity would likely hold off a bit longer.

Friday, while uncertain on exactly what could be expected to occur, the general outlook is of shortwave activity aloft combined with increased LLJ activity and low level pressure fields fronts all playing a role pointing toward an active weather day in some capacity. Severe concern seems limited at this time given models showing limited shear (25-40kts 0-6km). There may be enough with some LLJ activity to bring some concerns into Friday evening. The other concern that might become more concerning is a potential flash flood threat if we can get some training storms due to PWATs in the 1.5-2.0 inch range. Otherwise Friday into Friday night looks to be a case of if-then. If we clear the morning storms and showers earlier then it will leave a window of recovery ahead of the front which could enable an opportunity for some stronger evening storms. However, if the morning convection takes longer it may become the primary convection likely limiting severe risk (limited shear during the day), certainly in scope and recovery into the evening may not be as likely and limit higher end potential along the front. In any case we will be watching for other disturbances that may throw a wrench into everything, like perhaps a lingering MCV, which is why there is higher uncertainty on exactly what might occur.

In any case expect the front to come through late Friday night into early Saturday morning with some storms potentially lingering into Saturday morning depending of the fronts progression but developing high pressure to the north and troughing pushing east should push activity south of the CWA by Saturday morning. Some models keep some activity possible beyond earlier Saturday morning but limited midlevel moisture and lack of forcing seems unlikely at this time.

Note: Moderate swim conditions likely to be present for Sheboygan Thursday afternoon with wave heights approaching 3-4 ft but given latest trends should stay below high swim risk.

Kuroski

LONG TERM

Issued 215 PM CDT Wed Jun 3 2026

Saturday night through Wednesday:

The upper low is expected to move east, bringing a shortwave ridge though western WI Saturday night, decreasing the potential for continued rainfall. However, the precipitable water values of around 1.2" and high humidity could increase the chances of precipitation into early Sunday.

The slow-moving shortwave ridge is expected to remain over northeastern WI through Sunday morning and afternoon. A surface low pressure system over the Plains could increase the chance of precipitation Sunday night into Monday morning, with westerly/northwesterly winds bringing moisture to WI. The precipitable water values Sunday afternoon into the evening increase from around 0.9" to 1.6". Dewpoints will remain in the mid 60s Sunday into Monday morning.

As the shortwave ridge begins to move further toward Michigan and Ontario, a surface low is expected to move northeast from the Plains towards WI, creating the potential for precipitation Tuesday and Wednesday (20-40%). The attendant warm and humid airmass will bring chances for thunderstorms as well, particularly if a wave of convection were to initiate in the afternoon or evening.

Zawlocki

AVIATION

Issued 659 PM CDT Wed Jun 3 2026

VFR conditions will continue through tonight and Thursday. Light southerly winds are expected to continue through sunset along and west of the Kettle Moraine, while Lakeshore terminals through KUES will see gusty southeasterly winds off Lake Michigan. Winds will become light and variable to calm shortly after sunset, continuing into Thursday morning. Winds then shift to become southwesterly around 12 kt gusting to 20 kt midday Thursday into Thursday evening. Isolated showers may begin to develop from KMSN westward Thursday evening.

MH

MARINE

Issued 215 PM CDT Wed Jun 3 2026

High pressure around 30.4 inches will shift to the eastern US tonight. Light southerly winds tonight over the lake will become a bit breezy especially over the northern half into Thursday. Modest south to southwest winds will then prevail over the lake for into Saturday morning followed by a wind shift to the northwest during a cold frontal passage. Shower and storm chances will return Friday into Saturday morning. High pressure around 30.1 inches will redevelop to the north and envelop the region Sunday bringing light and variable winds back to the lake.

Otherwise and Small Craft Advisory remains in effect for Thursday afternoon and early evening for Port Washington to Sheboygan with wave heights creeping up into the 4 foot range for a period.

Kuroski

MKX WATCHES/WARNINGS/ADVISORIES

WI...None. LM...Small Craft Advisory...LMZ643...2 PM Thursday to 10 PM Thursday.