373
FXUS63 KGRB 171144
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
644 AM CDT Wed Jun 17 2026

Updated aviation portion for 12Z TAF issuance

.KEY MESSAGES...

- Showers and storms return today (80-100% chance). A few strong
  storms with small hail and gusty winds may occur, with the best
  potential across central to east-central Wisconsin.

- Moderate to heavy rainfall today will have a 60-80% chance of
  exceeding 1 inch of rain.

&&

.DISCUSSION...
Issued at 156 AM CDT Wed Jun 17 2026

Today...
A strong shortwave will drop into the region today, bringing back
widespread rainfall and some embedded thunderstorms. The
accompanying surface low will stay stretched across southern
Wisconsin and northern Illinois, which will keep the warm front
southwards as well. Therefore the strongest severe weather
potential will remain focused in these areas, so if you do have
travel plans in the direction of Milwaukee and Chicago today stay
weather aware. For our neck of the woods, overrunning moisture
will bring heavy rain potential into the area. Probabilistic
guidance has reduced the probability of exceeding 1 inch slightly,
but still remains in the 50-70% chance in a corridor from central
to east-central Wisconsin. For severe weather, potential will be
somewhat more limited for our area, but a few strong storms will
be possible in the mid to late afternoon after the initial showers
push through the area. Shear and upper forcing could suffice to
produce some hail and damaging winds with any stronger storms,
mainly for areas south of Highway 10.

Rest of the forecast...
Some isolated convection remains in the forecast for Thursday as
well, depending largely on surface heating to develop a few
showers in the region. While some thunder can`t be ruled out
severe weather is not expected.

Dry conditions then return for Friday and most of Saturday. The
next potential for active weather will arrive early Sunday morning
as the next strong system passes to our south. We are again on the
northern edge of this system, so early signs do not suggest this
will be a period of strong or severe storms for our area.

&&

.AVIATION...for 12Z TAF Issuance
Issued at 643 AM CDT Wed Jun 17 2026

VFR conditions will continue for the beginning of the TAF period
before periods of on and off showers arrive in the region. Showers
are expected to bring down ceilings across the area to MVFR/IFR by
the afternoon. Visibility may also lower at times within any areas
of heavy rainfall. Thunder potential appears limited but the best
chance will be during the afternoon. Confidence in storm placement
remained low, so forewent adding and thunder in the TAFs for now,
but would expect at least a few mentions during the afternoon. If
storms do form, some hail and gusty winds will be possible at
times.

Winds should pick up out of the west during the late morning to
afternoon with gusts up to 15 to 20 knots at times. Winds then
begin to diminish behind the front. Locally higher gusts will be
possible with any convection.

&&

.MARINE...
Issued at 156 AM CDT Wed Jun 17 2026

South to southeasterly winds this afternoon will bring increasing
winds and waves to the area today. A Small Craft Advisory and
Beach Hazards Statement have been issued for the Lake Michigan
shoreline as a result. The higher waves will linger into Thursday
morning, before winds shift offshore to the NW.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Beach Hazards Statement from 3 PM CDT this afternoon through
Thursday morning for WIZ022-040-050.
&&

$$

DISCUSSION.....Uhlmann
AVIATION.......Uhlmann
MARINE.........Uhlmann

NWS GRB Office Area Forecast Discussion