textproduct: Milwaukee/Sullivan

KEY MESSAGES

- More active pattern early next week, with increased shower and storm chances Sunday through mid-week. A short warm up is expected Sunday and Monday, with highs in the 60s and 70s, respectively.

- More chances for frost returning during the middle to late week period.

UPDATE

Issued 703 PM CDT Sat May 2 2026

Scattered to broken mid-level clouds may linger for at time this evening before dissipating. More mid-level clouds should push southeast into the area later this evening and overnight, lingering into Sunday. There is some warm air advection expected tonight into Sunday, along with a passing 500 mb vorticity maximum later tonight into Sunday morning.

These features should provide some upward vertical motion for more mid-level clouds and 20 to 30 percent chances for showers. These showers will need to overcome fairly dry air in the low levels overnight, before trying to moisten up for a time Sunday morning. It is possible that the showers end up gradually weakening of just having virga as they shift southeast through the area overnight into Sunday morning.

There may be a broken line of showers or perhaps a thunderstorm later Sunday afternoon, as an initial weak cold front pushes through the area. There is skinny mean layer CAPE a few hundred J/kg that tries to develop along and ahead of the weak front. Added in some 20 percent chances for showers in the northern areas for now to account for this.

Wood

SHORT TERM

Issued 132 PM CDT Sat May 2 2026

Tonight through Sunday night:

Dry weather will continue into tonight with west-northwest winds becoming southwesterly overnight as warm advection kicks in at the surface. Southwesterly winds will then become gusty Sunday morning as a stronger pressure gradient moves over the area ahead of an approaching cold front. Light rain showers are expected on a scattered basis along this front, with the best chances of seeing rain west of Madison. As these showers move east over southern Wisconsin, they will encounter a lot of dry air at the surface and may end of splitting most the east central portions of our area.

After the rain, skies will clear and gusty winds will taper off through the afternoon as the front arrives from the west and passes overhead. More warm advection is then expected Sunday night into Monday as southwesterly winds return again ahead of another cold front.

CMiller

LONG TERM

Issued 138 PM CDT Sat May 2 2026

Monday through Saturday:

Surface warm advection on breezy southwest winds will allow temperatures to rise into the low to mid 70s Monday. A cold front is expected to move through, with models converging on an early evening arrival of the front over central Wisconsin. Showers and a few storms are expected along the front Monday evening, but poor moisture return from the gulf will limit available CAPE. As such, skinny CAPE profiles will result, with limited potential for strong storms. Some gusty winds can't be ruled out with the strongest storms owing to dry levels from the surface to around 700mb, but these gusty winds should remain sub-severe.

Otherwise following the front, a cooler patter returns Tuesday through Thursday as a large trough dips into the Great Lakes region. Daily highs will be in the mid to upper 50s. Showers can't be ruled out at times given the steep lapse rates driven by the reservoir of cold air aloft and persistent northwest flow, though Thursday does look like the best day for shower activity at this time as the base of the upper level trough rotates through the area. Frost potential will also return Tuesday night through Thursday night.

Temperatures then begin to warm Friday into Saturday as ridging builds over the plains.

CMiller

AVIATION

Issued 703 PM CDT Sat May 2 2026

Scattered to broken mid-level clouds around 9000 feet AGL may linger for at time this evening before dissipating. More mid- level clouds should push southeast into the area later this evening and overnight, lingering into Sunday. Southwest winds should weaken this evening, as well as the southeast lake breeze for terminals near Lake Michigan.

Low level wind shear conditions may occur for a few hours later tonight into early Sunday morning, with southwest winds at 2000 feet AGL around 40 to 45 knots. Southwest winds should become gusty again later tonight into Sunday.

There are 20 to 30 percent chances for showers overnight into Sunday morning. These showers will need to overcome fairly dry air in the low levels overnight, before trying to moisten up for a time Sunday morning. It is possible that the showers end up gradually weakening of just having virga as they shift southeast through the area overnight into Sunday morning. May add some PROB30 groups for showers in TAFs for a few hours during the early morning.

There may be a broken line of showers or perhaps a thunderstorm later Sunday afternoon, as an initial weak cold front pushes through the area. Sheboygan would have the better chances of seeing this, but kept mention out of TAFs for now due to low confidence in reaching there. The gusty southwest winds should shift west after the front moves through, weakening Sunday evening.

Wood

MARINE

Issued 703 PM CDT Sat May 2 2026

Southerly winds grow breezy tonight into Sunday, as low pressure around 29.7 inches approaches the lake. A Small Craft Advisory is in effect Sunday for the nearshore waters for the gusty southwest winds. The low pressure system will drag a cold front southeast over the region Sunday morning into late Sunday afternoon. Winds will become westerly for a brief period behind the front Sunday night, before returning to southwesterly and becoming breezy again on Monday, ahead of another stronger low around 29.2 inches and another cold front.

CMiller/Wood

MKX WATCHES/WARNINGS/ADVISORIES

WI...None. LM...Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646...7 AM Sunday to 7 PM Sunday.