361
FXUS63 KGRB 100345
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
1045 PM CDT Sun Jun 9 2024

Updated aviation portion for 06Z TAF issuance

.KEY MESSAGES...

- Chilly tonight with patchy/areas of frost over north-central
  Wisconsin.

- Next round of active weather Tuesday afternoon. Next chance for
  more widespread thunder could be Wednesday evening.

- Below normal temperatures today through Tuesday with a warm-up
expected mid to late week.

&&

.DISCUSSION...
Issued at 308 PM CDT Sun Jun 9 2024

Short Term...Tonight and Monday

Main focus of the short term forecast will be on overnight low
temperatures.

A fast moving shortwave brought widespread cloud cover into the
area this afternoon, along with some gusty winds to around 25 mph.
A few sprinkles were reported in the Upper Peninsula early this
afternoon, and a few sprinkles may yet work their way into
northern Wisconsin near the Michigan border, but would not expect
any drizzle to make its way any further south than that.

As the shortwave clears the area this evening, rapid clearing in
cloud cover is expected across the region as much drier air
arrives. Between the departing clouds, slackening winds, and
falling dewpoints a fairly favorable setup for radiational cooling
is expected, so overnight low temperatures will drop fairly
quickly, especially across the north. With decent chunks of
north-central WI expected to get into the middle 30s, decided on a
frost advisory for the overnight hours.

Dry and quiet conditions then persist through Monday, making for a
fairly quiet day in the region. Sunny skies and high temperatures
into the upper 60s to middle 70s are expected.

Long Term...Monday Night Through Sunday

The main focus of the extended period will be on the upcoming
precipitation chances for the work week which will be in a fairly
active pattern.

The first chance for precipitation in the extended period will
cross the area Tuesday afternoon and evening as a shortwave
arrives behind the departing upper ridge. A narrow plume of
moisture and warmth along and ahead of the shortwave could support
some scattered precipitation. Instability however looks fairly
meager, with tall skinny profiles on the soundings, so while brief
thunder is possible, severe weather is not expected. Any
precipitation will be fairly short-lived however, as the rain
departs east rapidly.

Progressive flow brings the next round through later in the day on
Wednesday as another shortwave and frontal system cross the area.
Models continue to suggest initial development west of the region
and then bring things eastwards from there. Timing and placement
of the shortwave remain uncertain at this time however, as the
stronger storms may yet remain south of the area. Still, given the
potential for instability and decent shear Wednesday night, will
need to monitor late Wednesday for potential severe weather.

Finally, models do bring additional development late in the week
along the cold front from Wednesday, but the timing and placement
of any additional showers will largely be dependent upon where
the front from Wednesday lingers around the end of the week.

Temperatures will remain cool early in the week before warming up
over the next couple of days. How warm we get will depend on how
much cold air comes in behind the active weather during the week,
but at least some areas getting to the 80s seems reasonable.

&&

.AVIATION...for 06Z TAF Issuance
Issued at 1044 PM CDT Sun Jun 9 2024

Lingering clouds should clear out across eastern Wisconsin early
in the overnight hours, with mostly clear skies and VFR conditions
expected for the rest of the TAF period as high pressure builds in
across the western Great Lakes region.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Frost Advisory until 7 AM CDT Monday for WIZ005-010>012-018.
&&

$$

DISCUSSION.....Uhlmann
AVIATION.......Kurimski