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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS63 KMKX 182009
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
309 PM CDT Thu Apr 18 2024

.KEY MESSAGES...

- Another round of light rain today into this evening.

- Cooler pattern through the weekend may result in frost
  concerns Saturday night, especially in the Wisconsin River
  Valley.

- Dry pattern through this weekend, but a chance for rain
  Monday evening through Tuesday morning.


&&

.SHORT TERM...
-- Changed Discussion --
Issued 307 PM CDT Thu Apr 18 2024

Tonight through Friday night:

Southern WI will be sandwiched between two surface lows this
evening bring additional shower chances. As the southern low
currently located over MO to lifts across central IL/IN through
this evening, expect some of the rainfall activity to pick up
along the WI/IL border with totals nearing a quarter of an inch,
but could see a pocket or two of locally higher. However,
rainfall elsewhere looks to remain light with amounts around a
few hundredths of an inch to a tenth of an inch.

The southern low is progged to push east later tonight and
drier air moves into the region and rain chances diminish later
this evening. However, thinking the cloud cover may linger a bit
longer, but should gradually clear by daybreak Friday. Given
the clearing may see temps dip into the mid to upper 30s and
result in some patchy frost, but given the narrow wind between
the clouds clearing and temps dropping along with winds looking
to remain high enough, not confident on seeing widespread frost
development.

Northwesterly winds begin to pick up overnight into Friday as
the pressure gradient remains tight over southern WI as the
northern, stronger surface low meanders over central Ontario
while high pressure builds across the Plains. This will result
in breezy to gust northwesterly winds through Friday afternoon
with gusts 25-35 mph.

Otherwise, Friday should remain mostly dry with the building
surface high to the west. However cannot rule out a few light
showers across our central WI counties on the backside of the
northern low paired with the lingering upper-level trough, but
potential remains low (<15%). Friday should remain fairly clear
and sunny and despite the CAA/northwesterly winds, expecting to
see temps rise into the lower 50s by the afternoon. Winds will
gradually ease, but still remain breezy as the Ontario low
slides further east and influence from thew high spreads further
east into the start of the weekend.

Wagner
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&&

.LONG TERM...
-- Changed Discussion --
Issued 307 PM CDT Thu Apr 18 2024

Saturday through Thursday:

High pressure and zonal upper-level flow will persist through
much of the weekend. This will keep temps relatively cooler with
daily highs around or just below normal and overnight temps in
the 30s. Could see nightly frost potential Saturday and Sunday
nights given the near freezing temps and light winds. High
pressure will begin to slide further south-southeast ahead of an
upper-level trough early next week. Meanwhile southerly flow
will increase and looking to have a brief warm up toward the
start of next week. Then a more active pattern is expected for
Tuesday as long range models bring a surface low across the
region along with increased rain chances.

Wagner
-- End Changed Discussion --

&&

.AVIATION...
-- Changed Discussion --
Issued 307 PM CDT Thu Apr 18 2024

Lower ceilings and visibility have begun to spread into the
region this afternoon as off and on showers diminish in
coverage. however, another round of showers is progged to spread
in from the southwest through the afternoon and early evening
bring widespread MVFR ceilings and lower visibility with this
round of showers. The heavier rainfall is still progged for
areas around the WI/IL and may see visibilities drop below 2 sm
at times. However as the low pushes east later this evening,
expect a drier airmass to move into the region as rain chances
to diminish from west to east between 02z- 05z, but lower
ceilings may linger a few hours longer. Otherwise, expect light
variable winds to turn more northwesterly through the night
before increasing during the day Friday with gusts to 30kt.

Wagner
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&&

.MARINE...
-- Changed Discussion --
Issued 307 PM CDT Thu Apr 18 2024

Lake Michigan will be sandwiched between two areas of low
pressure. Expect lighter winds to continue through the evening
as the southern low pressure centered over MO this afternoon
lifts across central IL/IN. Meanwhile the northern low across
Ontario is progged to meander into the Hudson Bay region and
deepen through Friday. Expect a stronger pressure gradient
develop over the region for Friday with high pressure building
across the Plains resulting in 25-30 knot northwesterly winds
for Friday. High pressure is expected to gradually work its way
south-southeast through the weekend with lighter winds over Lake
Michigan. Then southerly winds return by the start of next week
ahead of a developing low over the Plains.

Wagner
-- End Changed Discussion --

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...None.
LM...Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646...10 AM
     Friday to 7 PM Friday.

&&

$$

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