140
FXUS63 KMKX 041943
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
243 PM CDT Tue Jun 4 2024

.KEY MESSAGES...

- Thunderstorms are expected to develop this afternoon. Isolated
  severe storms with wind and hail are possible during the
  afternoon to evening hours.

- Additional thunderstorms expected tonight through early
  Wednesday AM along a cold front. No severe weather is expected
  from these storms at this time.

- Localized heavy rainfall is possible this afternoon through
  tonight, and may lead to flooding.

- Northwest winds bring cooler and drier air to southern
  Wisconsin for the second half of this week.

&&

.SHORT TERM...
Issued 240 PM CDT Tue Jun 4 2024

Tonight through Wednesday night:

A negative tilt shortwave will continue to lift northeast this
afternoon and with increasing instability with upper 60 to near
70 degree DPs we should (30-50%) expect scattered storm
development later this afternoon into the evening. However with
little to no shear we expect these storms to largely be of the
popcorn style with limited severe risk with the only real risk
for hail up to an inch and brief strong gust from collapsing
storms. Latest CAMs suggest some storms but mostly weak and
lacking persistence.

As storms weaken as they slide northeast into the mid evening
that were associated with the shortwave we will then see the
effects of the longwave trough in west central Canada ejecting
another wave of energy through the area. This, in association
with the cold front, will be the cause of convection through the
afternoon in MN but the remnants of this convection will try to
slide through in the late evening and overnight hours. This is
expected to be weak if not actively dissipating as it pushes
across southern WI. Latest CAMs suggest that this and any
remaining activity from the early shortwave will likely (70%)
be weak.

Given PWATs upwards of 1.5 inches any storms could again be
efficient rain producers, but with storms likely being
transient and scattered expect mostly an isolated flooding risk.

Following the front we will see a brief period of quiet weather
behind the shortwave ejection overnight but then upper low in
Canada will again eject some shortwave energy into the western
Great Lakes for Wednesday afternoon and evening. Given some
decent midlevel lapse rates and enough low level moisture
behind the cold front we could expect a few weak storms and
showers but nothing severe would be anticipated at this time.

Kuroski

&&

.LONG TERM...
Issued 240 PM CDT Tue Jun 4 2024

Thursday through Tuesday:

We will remain under cyclonic flow until Friday night and then a
brief break in that flow (with weak ridging) is possible. With a
secondary closed upper low moving into south central Canada right
behind the exiting one, another embedded shortwave is expected to
trek across WI Saturday afternoon or night. The upper low will
remain overhead through Sunday night, so there is a chance for
showers and perhaps isolated thunderstorms each afternoon as well.

Highs will be around 70 through Monday, with lows in the lower
50s. Cloud cover should be primarily diurnally driven. Winds will
be out of the west-northwest through this period, and the speeds
will be higher, around 15 to 22 mph, each afternoon with peak
daytime heating and mixing.

Cronce

&&

.AVIATION...
Issued 240 PM CDT Tue Jun 4 2024

Mostly high clouds overhead with mostly mid to upper level
clouds expected through the early evening. We should see some
scattered storm development this afternoon and through the
evening though only a very small chance (5-10%) for a severe
storm in southern WI. Some heavier rainfall at times could
reduce VSBYS for brief periods. As the front pushes in late
this evening expect some MVFR/IFR CIGS to push in, which should
carry through the overnight period and even lingering into
Wednesday morning. CIGS could at times fall to LIFR or even
VLIFR but will gradually clear from the west into early to mid
Wednesday morning.

Otherwise expect modest southerly winds today with winds
turning to the west behind the front later this evening into
tonight.

Kuroski

&&

.MARINE...
Issued 240 PM CDT Tue Jun 4 2024

A low pressure trough will continue to slide east across south
central Canada tonight with southerly winds continuing ahead of
the associated cold front. Showers and thunderstorms are
possible late this afternoon through tonight. The cold front
will cross Lake Michigan Wednesday morning, causing winds to
veer westerly. Widespread showers and storms will end by around
noon Wednesday. Scattered showers are possible each afternoon
through the weekend. Westerly winds continue through the end of
the week as low pressure over south central Canada weakens.

Kuroski

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...None.
LM...None.
&&

$$

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