666
FXUS63 KMKX 151524
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
1024 AM CDT Sat Jun 15 2024

.KEY MESSAGES...

- Chance for thunderstorms late Saturday into Sunday.

- Hot weather is anticipated Sunday into the middle of the work
  week. Heat indices in the middle 90s are likely Sunday and
  Tuesday and heat index values in the upper 90s are likely on
  Monday.

- Additional chances for storms the rest of this week.

&&

.UPDATE...
Issued 1025 AM CDT Sat Jun 15 2024

With the ridge now over the region we have dried out quite a
bit, especially in the low to mid levels. There has been some
embedded shortwave activity aloft that is associated with good
moisture gradually sliding in this morning, however the low
level dry air has largely prevented any precip from reach the
ground. We cant rule out a few sprinkles in our far west but it
remains likely (80%) to be virga.

As the system pushes in through the day and particularly into
the evening we will gradually moisten up in the low levels,
though primarily further west. It will likely (80%) remain
drier further east. The upper level shortwave will continue
through the region into the evening and overnight but the
difference will be the LLJ jet building into the region which
will enhance forcing in the mid levels. The issue with this is
the LLJ will largely be setting up further west. Given the drier
air further east it could set up a fairly stark boundary for
dry and wet. There is some storm potential with this given the
LLJ and enhanced shear (30-40kts) that it will provide but given
the timing the instability will be rather low so any storms are
largely expected to be weak. The best chances (80-90%) for
precip/storms from this system will be further northwest though
the entire northwest half of the CWA will see chances (60-90%)
with the southeast more likely (60-80%) to remain dry.

This system will slide out by Sunday morning with the rest of
Sunday looking dry. Late Sunday night into Monday morning we
should expect the LLJ to ramp up again, though weaker in our
region. The LLJ will increase in strength into the day Monday
with general shower/thunderstorm chances (30%) expected.

Kuroski

&&

.SHORT TERM...
Issued 351 AM CDT Sat Jun 15 2024

Today and Tonight:

High pressure over Ontario will bring light southeast winds. Cirrus
associated with convection over the plains will continue to spread
into southern Wisconsin. Showers over Minnesota and Iowa associated
with a weak shortwave within mid level ridging should dissipate as
they move into southern Wisconsin an encounter drier air.

There is a 20% chance for thunderstorms this evening north and west
of Madison as a deeper shortwave approaches the region. Storm
chances expand across southern Wisconsin overnight as the shortwave
moves through and increase to over 75% north and west of Madison.
Areas south and east of Madison may stay dry. A 40 knot low level
jet will shift into western Wisconsin during this time bringing a
surge of moisture. Some storms may be on the strong side as
instability builds to 1500 MU CAPE early Sunday morning with 20 to
30 knots of shear.

Marquardt

&&

.LONG TERM...
Issued 351 AM CDT Sat Jun 15 2024

Sunday through Tuesday

Some showers may linger into Sunday morning before ridging builds
back in. Can`t rule out a thunderstorm during the afternoon, which
the HRRR shows, but we are capped around 850 mb. Much warmer and
more humid temperatures are expected for the early part of next
week. A strong mid level ridge sets up over the southeast U.S.
bringing as low pressure develops over the central plains. This
brings strong and moist southerly flow into the region. Highs will
be around 90 with heat index values in the 90s. Some areas may see
values near 100 on Monday.

There is a 30% chance of storms on Monday and Tuesday. Many areas
will be dry. The better chances will be to our northwest where a
strong low level jet surges into a frontal boundary draped
across Minnesota into northern Wisconsin.

Wednesday through Friday

Warm temperatures will continue but likely will not be as warm as
earlier in the week. The frontal boundary will push southward
through the state sometime early in the period bringing a better
chance for rain and thunderstorms.

Marquardt

&&

.AVIATION...
Issued 1025 AM CDT Sat Jun 15 2024

VFR conditions are expected through the TAF period. However,
while much of the day is expected to remain quiet as we head in
the late evening and overnight period we will see chance for
showers and maybe even a few weak storms. Most of this is
expected to remain off toward west central WI. There remains a
decent chance (50%) for a shower or storm closer to Madison but
the better chance will remain north and west. Thus there remains
a slight chance (20%) for a period of MVFR VSBYS. Otherwise MVFR
CIGS will likely (80%) remain off to the north and west of
southern WI. Scattered CIGS expected across most of southeast WI
during this period. System will push out Sunday morning.
Otherwise expect southerly winds gradually increasing overnight
into Sunday, turning more SSW and persisting through much of
the day.


Kuroski

&&

.MARINE...
Issued 351 AM CDT Sat Jun 15 2024

South winds increase on Sunday with building waves. The northern
half of the open waters will see some gusts around 30 knots.

Issued a small craft advisory from 4 AM Sunday to 10 pm Sunday.
Strongest winds will be during the day, then waves will linger into
the evening.

Fog may develop for Sunday night and Monday and may linger through
the early part of the week with the humid air mass over the lake.
South winds will increase again Monday night through Tuesday night.
Gusts in the open waters may reach 30 knots.

Marquardt

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...None.
LM...Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646...1 AM
     Sunday to 1 AM Monday.

&&

$$

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