National Weather Service Raw Text Product

008 
FXUS63 KGRB 132313
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
613 PM CDT Fri Jun 13 2025

.KEY MESSAGES...

- Periods of showers expected through the weekend, especially west
  and north of the Fox Valley/lakeshore areas.

- Stormy period expected for at least the early to mid part of the
  next work week.

&&

.DISCUSSION...
Issued at 308 PM CDT Fri Jun 13 2025

Widespread showers associated with an 850 mb warm front and 
850-700 mb frontogenesis still covered most of northern WI
this afternoon, but were gradually decreasing over north central
WI. Rain-cooled air was holding temperatures in the upper 40s to
middle 50s north, while readings had climbed into the upper 50s
and lower 60s in parts of central and east central WI.

Precipitation Chances through the Weekend: Expect the more
concentrated showers to exit far NE WI as forcing weakens this
evening, though isolated to scattered showers may persist in the
Northwoods well into the evening. A gradual increase in showers 
can be expected in NC WI late tonight into Saturday morning, as 
additional weak WAA/FGEN arrive. These showers will be of the 
light to moderate variety, and should become more scattered as 
they drift southeast during the day. The chance of showers 
persists Saturday night into Sunday, with an uptick in activity 
and even a few thunderstorms possible into our southwest counties
as modest instability arrives Sunday afternoon. Canadian high 
pressure will continue to produce light to moderate easterly winds
through the weekend, which when combined with periodic showers, 
will result in below normal temperatures across the Northwoods.

Stormy Period expected during the next Work Week: The Canadian
high will shift east early next week, allowing for southerly
winds to develop and bring warmer, more moist and unstable air 
into the region. A cold front will approach NW WI late Monday into
Monday night, and may trigger a round of storms, which would
then move into the forecast area. The front will edge eastward
Tuesday into Wednesday, with possible rounds of convection
developing as a couple short-waves move through the region, and a
surface wave lifts north along the boundary on Wednesday. 
Although timing is uncertain, this period has potential for severe
weather, as a much more unstable air mass will be in place, and
deep layer shear will be sufficient for storm organization. Storm
chances are more uncertain later in the week, as models diverge.
This will be be a warmer and more humid period, at least through 
midweek.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/... 
Issued at 613 PM CDT Fri Jun 13 2025

IFR to MVFR ceilings will impact central into northern Wisconsin
tonight into Saturday.  

Widespread IFR/MVFR stratus will remain in place across the
region tonight with some improvement expected on Saturday. The
Fox Valley, including KGRB/KATW may reside on the southern edge
of the lower stratus shield, so confidence is lower for cloud
trends in this area. Both the NBM and 13.12Z HREF show
probabilities in the 30 to 50% at KGRB/KATW for MVFR ceilings at
KATW/KGRB overnight into Saturday morning with a higher 
likelihood for VFR by afternoon. MVFR visibilities will be also 
be possible (40-60% chance) across parts of northern Wisconsin 
overnight. 

Areas of showers will persist through the TAF period. Exact
timing and coverage remains somewhat uncertain, but the higher
chances (40-70%) are focused across central into northern 
Wisconsin overnight and Saturday.

Winds will remain easterly through Saturday.

&&


.GRB WATCHES/WARNINGS/ADVISORIES...
WI...None.
MARINE...Small Craft Advisory until 10 PM CDT this evening for LMZ521-
     522-541>543.

&&

$$

DISCUSSION...Kieckbusch
AVIATION...JM