National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS63 KMKX 280929
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
429 AM CDT Sun Apr 28 2024

.KEY MESSAGES...

- Showers and storms are possible today, especially this
  afternoon and evening. An isolated strong to severe storm
  can`t be ruled out. The flash flood threat will remain low but
  local urban and small stream flooding is more probable.

- Another round of showers and possibly a rumble of thunder
  Tuesday evening/night. A stronger system with additional
  showers / thunderstorms Wednesday night through Thursday,
  possibly continuing into Friday.

- Above normal temps likely Monday through Thursday, cooling off
  towards normal this weekend.

&&

.SHORT TERM...
Issued 420 AM CDT Sun Apr 28 2024

Today through Monday:

The cold conveyor behind the departed low pressure and the warm
sector of an approaching low pressure over the central plains
have created a stalled front, the exact position of which
remains uncertain going into this afternoon. Some models take it
as far north as a Racine to Madison line by this afternoon,
while others keep it right on the WI / IL border, or even south
of the border for eastern areas (near the refrigerating effect
of Lake MI). Our latest temperature forecast places it along a
Kenosha to Mineral Point WI line, with daytime highs in the
upper 40s to mid 50s north of the boundary and mid 60s south of
it.

Showers and thunderstorms are likely to develop near and north
of the front today. A few strong to severe storms cannot be
ruled out, especially along and south of the warm front. HREF
ensemble mean MUCAPE holds around 500 j/kg near the warm front
today, possibly surging over 1000 j/kg this afternoon into this
evening as the stalled front begins a northward advance as a
warm front. The warm front fully crosses the CWA tonight into
early Monday morning, allowing one last chance for increased
shower / thunderstorm coverage. Storm coverage is expected to
decrease into Monday as a dry slot wraps into the low pressure,
though some models indicate scattered to isolated redevelopment
of showers / thunderstorms with lingering 850mb humidity.

Sheppard

&&

.LONG TERM...
Issued 420 AM CDT Sun Apr 28 2024

Monday night through Saturday:

Dry weather is expected Monday night through Tuesday, as high
pressure briefly moves through the area. Southerly winds Tuesday
ahead of an approaching low will push temps back into the 70s most
places, aside from cooler temps east as winds will likely turn
onshore in the afternoon.

A trough will then likely swing through the area Tuesday
evening/night, bringing a round of showers to southern Wisconsin.
There may be a few rumbles of thunder as well, given some weak
elevated instability.

High pressure will briefly return on Wednesday, with dry weather
and mild temps in the 70s once again. A stronger low pressure
system is then expected to gradually lift through the region
Wednesday night through Thursday, possibly even lingering in the
area into Friday per slower models solutions. Rounds of showers
are likely (60%+) at times with this system, with some occasional
thunder also possible. Models currently are showing the highest
chance for thunderstorms on Thursday, as the warm sector pushes
into or close to southern Wisconsin. Above normal temps are likely
through Thursday, cooling back towards normal by the weekend.

DDV

&&

.AVIATION...
Issued 420 AM CDT Sun Apr 28 2024

MVFR / Fuel Alt cloud ceilings have increased in coverage over
the past few hours. This trend of lowering cloud ceilings (and
possibly development of patchy fog) is expected to continue this
morning, due to northeast winds advecting a rain-humidified
lake-refrigerated airmass off of Lake Michigan. Widespread IFR
cloud ceilings become likely later this morning, with multiple
rounds of showers and thunderstorms.

A stalled front just south of the region begins a northward
advance as a warm front tonight, causing winds to veer south,
eventually southwest on Monday. Another round of showers is
expected (possibly with thunder) throughout this period, with
shower and storm coverage likely decreasing into Monday. Cloud
ceilings gradually lift to VFR throughout Monday.

Sheppard

&&

.MARINE...
Issued 420 AM CDT Sun Apr 28 2024

Low pressure around 29.7 inches drifts northeastward through Quebec
early this morning. Its cold front has already crossed two thirds of
the lake, and will stall near the southern end of the lake today as
the warm front of an approaching low pressure system collides with
it. Thus, north to northeast winds are expected across the majority
of Lake Michigan today, with the fastest winds (up to 30 kts) in
central Lake Michigan. Expecting light and variable winds over the
southern third of the lake (near the stalled front) and south winds
at the far southern tip of the lake.

Modest east to southeast winds will then develop over all of the
lake tonight as the stalled front moves north as a warm front. Brisk
east winds, possibly reaching gale force, are expected over the
northern tip of the lake late tonight into Monday morning. Breezy
south winds will develop over the remainder of the lake on Monday.

Areas of fog may form over the lake today, especially the southern
half. Several rounds of showers and thunderstorms are expected
between now and Monday.

Sheppard

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...None.
LM...Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646 until 7 PM
     Monday.

&&

$$

Visit us at weather.gov/milwaukee

Follow us on Facebook, Twitter, and YouTube at:
www.facebook.com/NWSMilwaukee
www.twitter.com/NWSMilwaukee
www.youtube.com/NWSMilwaukee