Minocqua, Wisconsin Weather Forecast Discussion

693
FXUS63 KGRB 210448
AFDGRB
Area Forecast Discussion
National Weather Service Green Bay WI
1148 PM CDT Sat Sep 20 2025
Updated aviation portion for 06Z TAF issuance
.KEY MESSAGES...
- Multiple rounds of showers and thunderstorms are expected through
  Monday. Isolated strong storms with gusty winds, small hail,
  and heavy rain with localized flooding will be possible at
  times.
- Patchy to areas of fog are likely to occur at times tonight,
  especially for locations north and west of the Fox Valley.
  Locally dense fog is possible.
- Above normal temperatures are expected for much of next week.
&&
.DISCUSSION...
Issued at 310 PM CDT Sat Sep 20 2025
SHORT TERM (This Afternoon through Sunday)
First upper level disturbance moved away from the area late this
morning, bringing a lull in the shower and storm activity early
this afternoon. The second piece of energy was moving towards the
area as of mid-afternoon. In response, scattered showers and
thunderstorms developed across central and east-central WI. The
local mesoanalysis page indicated surface based CAPE values of
1,000-1,800 J/KG across central and east-central WI. 0-6km shear
values were around 25 knots. The upper level feature is expected
to move across the area for the rest of the afternoon into this
evening, bringing scattered showers and storms to the area. The
risk of severe weather is low, however an isolated severe storm
with 1" inch hail can`t be ruled out. As the feature moves away
from the area later tonight, the shower and storm activity will
wane. With the upper trough overhead, can`t go completely dry
later tonight as a few isolated showers could pop up at times.
Also, areas of fog are possible later tonight. The HREF indicated
a 30-60% probability of visibilities dropping below one mile,
especially north and west of the Fox Valley. Any lingering fog
will burn off by mid-morning on Sunday, then the chances of
showers and storms will increase during the late morning and
afternoon. Lows tonight will drop into the middle 50s to lower 60s
with highs Sunday in the upper 60s to middle 70s.
LONG TERM (Sunday Night through next Saturday)
The 500mb trough will linger through Monday, bringing continued
chances of showers and thunderstorms. 500mb heights will begin
to rise Monday night and Tuesday as ridging develops across the
northern plains into the western Great Lakes. By the middle of
next week, ensemble height anomalies indicate a ridge will develop
over central Canada while a low-pressure system forms over the
Ozarks. This pattern will help funnel drier, more stable air into
the region, shunting most of the precipitation chances south of
the area through Thursday. The GFS model indicated a decent
rainfall event Wednesday into Thursday, but was the outlier
at the moment. Temperatures for much of next week will end up
above normal.
&&
.AVIATION...for 06Z TAF Issuance
Issued at 1147 PM CDT Sat Sep 20 2025
Scattered showers continued in portions of east-central and far
northeast WI late this evening. However, they were not impacting
the east-central WI TAF sites, and should continue to not impact
these sites. Instead, a low deck, with cigs of 100 to 500 ft AGL,
moved into portions of central and north-central WI. Regardless of
these cigs and lower vsbys moving into these areas a bit sooner
than previously forecast, anticipate the cigs and vsbys to
continue to bounce in and out of IFR/LIFR through 13-15z. The
signal continues to look less impressive over the east-central WI
TAF sites, but continued to include TEMPO groups with MVFR/IFR
conditions during early Sunday morning.
Models have lowered the coverage and likelihood of isolated
showers developing Sunday afternoon/evening. But, there is still a
signal for RHI to see some showers, so have included a PROB30 for
rain showers. Depending on how conditions evolve Sunday
afternoon, the mention of showers may need to be added to other
TAF sites.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
DISCUSSION.....Eckberg
AVIATION.......Kruk

NWS GRB Office Area Forecast Discussion