187
FXUS63 KGRB 070722
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
222 AM CDT Mon Jul 7 2025

Forecast discussion for routine morning forecast issuance

.KEY MESSAGES...

- Seasonal summer weather is expected this week. Shower and
  thunderstorm chances expected tonight into Tuesday, and again
  Friday into Friday night.

&&

.DISCUSSION...
Issued at 219 AM CDT Mon Jul 7 2025

Today...

Mid-level clouds have developed over central and north-central WI
early this morning limiting the potential for fog to develop.
Will continue to monitor obs for any patchy ground fog that
develops early this morning, but widespread dense fog has become
unlikely.

A dry continental airmass in place over the region will deliver
pleasant summer conditions today. Highs this afternoon will reach
the upper 70s to low 80s at most locations with comfortable humidity
levels (dew points in the low 50s to around 60 degrees).

Precipitation Chances...

Next chance for precipitation arrives late tonight as an upper-
level short- wave tracks along the US/Canada border toward Lake
Superior. Severe weather parameters are not that impressive during
the period, CAPE 500-1000J/kg, 0-6km shear 25-30kts, and PWATS
1.3- 1.4 inches. Likely result will be scattered to widespread
showers through Tuesday morning with a few isolated thunderstorms
developing during the late morning and afternoon. Total rainfall
amounts are also not expected to be overly impactful as current
NBM probs for greater than 0.5" are only 30-40%. Probs fall to
10-15% for the chance of greater than 1".

Another round of rain is expected Friday and Friday night as a more
amplified trough digs over the upper Midwest. Similar to Tuesday
severe weather parameters are not all that impressive. PWATs are
higher (1.6-2") which could point to the potential for periods of
heavier rainfall within any stronger thunderstorms. However, global
ensembles show very weak vertical wind fields suggesting storms will
have a difficult time becoming organized and long lived.

Temperatures for the remainder of the week should remain seasonal
with limited humidity most days.

&&

.AVIATION...for 06Z TAF Issuance
Issued at 1051 PM CDT Sun Jul 6 2025

Mainly VFR conditions are expected through the TAF period. The
exception will be if fog can develop overnight. Chance for
widespread fog remains under 20% with no major change in the 00z
guidance, but with the recent rain, would expect at least some
patchy ground fog to develop overnight across parts of central and
north central WI (especially in/near the Wisconsin River Valley),
where winds are the lightest (under ~5 kts). Have continued with
TEMPO groups between 08z-12z/Mon for fog at RHI/AUW/CWA. Across
eastern WI, there was more rain over the past 24-36 hours, but
winds in the boundary layer are a little stronger (5-10 kts), so
it will be more of a challenge to get fog to form. Will hold off
on any TEMPO groups at GRB/ATW/MTW and monitor trends.

Monday will be dry with light winds. Chances for showers and
storms return Monday night into Tuesday morning. Some elevated
smoke could make for a hazy sky at times through the TAF period.

&&

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

&&

$$

DISCUSSION.....GK
AVIATION.......Bersch