149
FXUS63 KGRB 022337
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
637 PM CDT Thu May 2 2024

Updated aviation portion for 00Z TAF issuance

.KEY MESSAGES...

- Scattered showers and a few thunderstorms will develop ahead of
  a cold front tonight. No severe weather is expected.

- Due to recent and upcoming rainfall, rivers and streams will
  continue to rise late this week. Some rivers are forecast to
  remain at or reach bankfull stage.

- Light showers are possible Saturday into Saturday night, with
  more widespread shower and thunderstorms possible Tuesday into
  Wednesday.

&&

.DISCUSSION...
Issued at 323 PM CDT Thu May 2 2024

Short Term...Tonight and Friday

Precipitation chances continue tonight, with much drier
conditions expected on Friday.

A large area of showers associated with strong H8 WAA and a
short-wave trough will continue to lift north out of the region
late this afternoon. Low pressure over NE IA with lift northeast
into the forecast area this evening, and drag a weak cold front
through the region overnight. Showers, abundant cloud cover and
east winds have combined to maintain a stable air mass over GRB
CWA this afternoon, though weak elevated instability (H8 LI`s of 0
to -2 C) will lift into the region this evening then shift east
as the cold front shifts east later tonight. Scattered showers
and a few storms are expected to develop ahead of the front,
though the general trend is for a less rainy night than was
earlier expected. Lows tonight will be in the 40s and lower 50s.

On Friday, high pressure and a much drier air mass will move into
the forecast area. Deep mixing will promote warm temperatures
in the upper 60s to middle 70s, west winds gusting to 20 to 30 mph
(strongest in northern WI) and low relative humidity in the sandy
soil areas. Today`s rain should mitigate any fire weather
concerns.

Long Term...Friday Night Through Thursday

Dry high pressure will linger through Friday night, but a weak
inverted surface trough and short-wave will bring a chance of
showers on Saturday and Saturday evening. This is looking like a
light precipitation event at this time.

High pressure moves back into the region Sunday into Monday, with
another round of mild temperatures and low humidity expected.

A deep upper level low over the Northern Plains will lift potent
short-wave energy into the western Great Lakes late Monday night
through Tuesday night, bringing good potential for a round or two
of showers and storms. The remnants of this system will linger
near the region late in the week, with smaller chances of showers
and storms.

&&

.AVIATION...for 00Z TAF Issuance
Issued at 637 PM CDT Thu May 2 2024

Ceilings will lower tonight and become IFR west of a ESC to DLL
line, with MVFR ceilings to the east. Scattered light rain or
drizzle will end overnight as a surface front moves across the
area late tonight. Skies will clear Friday morning as a weak
surface high moves in from the Central Plains. Good flying weather
is expected Friday night.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION.....Kieckbusch/Kieckbusch
AVIATION.......RDM