000
FXUS63 KGRB 170430
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
1130 PM CDT Tue Apr 16 2024

Updated aviation portion for 06Z TAF issuance

.KEY MESSAGES...

- Elevated fire weather conditions will persist into early this
  evening across northern Wisconsin due to low relative humidity
  and gusty east winds.

- Showers and a few embedded thunderstorms are expected tonight into
  Wednesday. Widespread severe weather is not expected, but some
  of stronger showers and storms could produce a brief period of
  wind gusts over 50 mph. Small hail is possible with some of the
  stronger thunderstorms. Locally heavy rainfall is possible.

- Strong east to southeast winds are expected this afternoon into
  tonight, with gusts of 30 to 50 mph. The strongest gusts are
  anticipated across central, east-central, and portions of north-
  central Wisconsin where a Wind Advisory has been issued.

- The strong easterly winds may produce some localized blowing
  dust across southern Wood and western Waushara counties,
  especially on Highway 54 in Wood County and Interstate 39
  between Plover and Coloma. Once the rain arrives by early
  evening, the risk of blowing dust will come to an end.

&&

.DISCUSSION...
Issued at 315 PM CDT Tue Apr 16 2024

Short Term...Tonight and Wednesday

Another day with elevated fire conditions across the north due
to low humidly readings in the 15 to 30 percent range along with
increasing winds. The strong winds were also causing areas of
blowing dust across southern Wood and western Waushara counties,
especially on Highway 54 and on Interstate 39 between Plover and
Coloma. Any blowing dust will come to an end once the rain
arrives.

The band of showers and thunderstorms will move into central
Wisconsin late this afternoon and across the Fox Valley and
lakeshore early this evening. Bufkit soundings indicated between
300 and 600 J/KG of CAPE. The main story will be the strong winds
off the deck. Any shower or storm this evening could produce a
wind gust over 50 mph. The first band of showers and storms will
move into far northeast Wisconsin towards midnight. There will be
a break or lull in the shower and storm activity with subsidence
behind the first cluster of storms. The next round of steadier
showers and storms arrives late tonight into early Wednesday
morning, with the greatest focus across central Wisconsin.

For the Wind Advisory, moved up the end time across central
Wisconsin as winds slacken off there first. I kept the end
time across east-central Wisconsin due to strong winds off
the lake will continue longer into the night. It is possible
that the advisory may be cancelled early. Showers and a few
storms will continue Wednesday morning with a decrease in the
activity during the afternoon. High temperatures will range from
around 50 north and in the lower 60s across central and east-
central Wisconsin.

Long Term...Wednesday Night Through Tuesday

Precipitation...A few rain showers may linger into Wednesday
night as a low pressure system shifts off to the northeast, but
with dry air at the mid and upper levels progged to pushed over
the region expect most of the area to turn dry overnight Wednesday
into Thursday. Models are in decent agreement with a disturbance
supported by an right rear jet quad moving south of the region
Thursday afternoon/evening that may bring a round of rain to
central and east-central WI. There is more uncertainty with the
potential for rain across northern WI during this time as some
models are showing the development of a surface low over the UP
creating a convergence boundary across northern WI, while other
models don`t have this feature at this time.

The region will remain in the cyclonic flow of a system slowing
moving into Quebec Friday. An area of cold air advection may
bring a period of mixed precipitation through Friday evening,
with forecast soundings showing a sufficiently cold profile for
the possibility of all snow across northern WI, however, with the
warm ground any accumulations should be minimal. A ridge of high
pressure is then expected to for this weekend returning dry
conditions to the region. Next chance for any precipitation then
looks to come early next week, but there is not enough of a model
consensus to dig too much into the details at this time.

Temperatures... Temperatures on Thursday will be dependent an any
precipitation that forms and if a surface boundary develops, for
now have high temperatures a few degrees above normal with most
areas in the middle to upper 50s. The cold air advection will
bring cooler temperatures Friday and Saturday with highs expected
to be a few degrees below normal. Highs in the low 40s to low 50s
are expected each day. As surface winds back and become
southwesterly Sunday into Monday slightly above normal
temperatures are expected to return.

&&

.AVIATION...for 06Z TAF Issuance
Issued at 1130 PM CDT Tue Apr 16 2024

Flying conditions will continue to fall into the MVFR/IFR
categories late this evening and overnight as a strong low
pressure system tracks towards the state. The first large area of
showers and isolated/scattered storms will continue to spread
across the area late this evening. A lull in the showers/storms
is expected for a time overnight, then another wave will arrive
Wednesday morning as the low moves across northeast WI. A few LIFR
conditions are possible overnight into Wednesday morning.

East winds of 15-30 kts, with a period of lighter more variable
winds at times, will continue this evening then slowly decrease
overnight into Wednesday morning as the low moves overhead. Winds
will shift to the west by Wednesday evening and gust up to 30 kts.
Locally higher gusts are possible in/around any heavier
showers/storm.

LLWS is expected as winds at 2000 ft remain at 45-60 kts for much
of the night. LLWS will end Wednesday morning as the winds aloft
decrease. Marginal LLWS will be possible Wednesday evening as
winds at 2000 ft increase to around 40 kts, but surface gusts
could limit the amount of shear.

&&

.MARINE...
Issued at 315 PM CDT Tue Apr 16 2024

A Gale Warning remains in effect for tonight. Easterly winds have
been increasing this afternoon and will reach gale force tonight.
Winds will diminish overnight, thus a down grade to a Small Craft
Advisory is expected late tonight into Wednesday morning.

&&

.FIRE WEATHER...
Issued at 315 PM CDT Tue Apr 16 2024

Afternoon relative humidity values dropped into the 20 to
30 percent range across the north. Easterly winds have been
on the increase this afternoon. The elevated fire weather
conditions will come to an end this evening as humidity values
rise and the rain arrives.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 4 AM CDT Wednesday for WIZ038>040-048>050.
&&

$$

DISCUSSION.....Eckberg/GK
AVIATION.......Bersch
MARINE.........Eckberg
FIRE WEATHER...Eckberg