NWS-Milwaukee/Sullivan Forecast Discussion
FXUS63 KMKX 030003 AAA
AFDMKX
Area Forecast Discussion...UPDATED
National Weather Service Milwaukee/Sullivan WI
703 PM CDT Sat May 2 2026
.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.
&&
$$
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