NWS-Green Bay Forecast Discussion

						FXUS63 KGRB 090555
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
1255 AM CDT Sat May 9 2026

Forecast discussion for routine afternoon forecast issuance

.KEY MESSAGES...

- Temperatures will be below normal into the middle of next week,
  with frost possible Sunday and Monday mornings.

- A small chance (15-35%) for rain showers in central and east-
  central WI this morning. There is a greater chance for precip on
  Tuesday (~80%).

- Periods of elevated fire weather conditions will exist during
  the late mornings and afternoons over the next few days due to
  low humidity, breezy winds, and drying fuels.

&&

.DISCUSSION...
Issued at 1255 AM CDT Sat May 9 2026

Surface cold front was just getting to northwest Wisconsin at 05Z
as evident by a wind shift to the northwest and lower clouds.
Rain is occurring behind the front across part of central
Minnesota. This front will be the main weather feature to impact
central and northeast WI today, bringing a return to cooler temps
and small rain chances.

Precipitation: Cold front moves across the area this morning,
which coincides with a mid-level shortwave across northern WI, and
upper jet across southwest WI. Despite this forcing, forecast
soundings still show very limited moisture, and pwats of only 0.3
to 0.6" across the area. LREF probabilities of getting at least
0.10" of rain are about 10-20% from central into east-central WI,
and less than 10% across the north. Upstream radar trends show the
area of rain is shrinking as it moves east and encounters drier
air, but CAMs show a broken area of rain holding together and
reaching at least central WI. CAMs in general show a stronger
signal for precipitation than the past few days where mainly
sprinkles/virga have materialized. Therefore, continued low-end
PoPs (15-35%) across central into east-central WI for this
morning, with diminishing potential after that. Amounts would be
very light, with just a few hundredths forecast.

A more organized clipper system remains on track to move through
the Upper Midwest early next week, impacting Wisconsin on Tuesday.
This is the greatest opportunity to see rain over the next week,
with probabilities of getting at least 0.10" now up to ~80%.
The potential for half an inch of range is ~15%.

Temperatures: High temps today will be in the 50s across north-
central WI where the cold front arrives earlier. The rest of the
area will get into the low 60s, a few degrees below normal. The
cooler air sticks around into early next week, with the potential
for frost Sunday and Monday mornings. By late next week there are
indications of a change to above normal readings, with highs in
the 70s by Thursday or Friday.

&&

.AVIATION...for 06Z TAF Issuance
Issued at 1051 PM CDT Fri May 8 2026

VFR conditions (mainly mid to high clouds) through Saturday.
Borderline MVFR cigs could occur over central WI Saturday
morning. Small chance (20-30%) for a few light showers over
central WI (AUW/CWA) in the morning as a cold front moves
through. A few light showers or sprinkles could pop-up over
eastern WI late in the afternoon, but have maintained a dry
forecast for now. Skies will clear out on Saturday night.

West winds shift northwest late tonight. There will be a round of
LLWS from central to eastern WI late tonight into Saturday
morning. Otherwise, NW winds on Saturday will gust over 20 kts
late morning through the afternoon in wake of the cold front.
Also, hint of a re-inforcing cold front and/or a lake breeze late
day (after 22-23z) that may impact GRB to MTW, shifting winds to
the N/NE. Winds will become light and variable Saturday night.

&&

.FIRE WEATHER...
Issued at 1255 AM CDT Sat May 9 2026

Brief periods of elevated fire weather conditions will occur over
the next few days due to deep mixing, low RHs, moderate winds,
and increasing dry fuels. Forecast soundings for today once again
show deep mixing to 8-10kft, bringing down sfc wind gusts to
around 30 mph. Minimum RHs today are forecast to be in the 25-35%
range away from Lake Michigan.

&&

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

&&

$$

DISCUSSION.....KLJ
AVIATION.......JLA
FIRE WEATHER...KLJ