826
FXUS63 KGRB 160810
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
310 AM CDT Tue Jun 16 2026

Forecast discussion for routine morning forecast issuance

.KEY MESSAGES...

- Showers and storms expected (60-90% chance) this afternoon.
  Storms are not expected to be severe but some brief gusty winds
  and small hail are possible.

- Another round of showers and storms are expected for Wednesday
  (80-100% chance). Potential for organized severe weather remains
  low, but a few strong storms with small hail and gusty winds may
  occur. Moderate to heavy rainfall will have a 60- 80% chance of
  exceeding 1 inch of rain.

- Below average temperatures in the 60s and 70s through the week.

&&

.DISCUSSION...
Issued at 310 AM CDT Tue Jun 16 2026

A period of active weather is expected through the middle of the
week as a pair of shortwaves move through the area. Additional
rain chances then arrive towards the middle of the week as well.

Today...
A shortwave trough will cross the region today, bringing
a wide area of rain and a few storms into the area for the
afternoon and evening. Modest instability near the surface
combined with upper support from the shortwave will support
scattered convection, but with a lack of shear more organized
storms are unlikely. Therefore would expect most storms to be
short-lived and pulse-like. Although this setup will not favor
severe storms, given the relatively low freezing levels and decent
mid-level lapse rates around 7 C/km, would expect some small hail
to be possible within any storms.

Wednesday...
Another, stronger shortwave drops towards the region on
Wednesday, bringing another round of showers and storms into the
region. The track of the accompanying surface low remains somewhat
variable, but most mid to long range guidance does keep it south
of the region. This would keep the warm front and more unstable
air and moisture south of the area, and greatly limit the overall
severe potential in northeastern Wisconsin. That said, some
overrunning moisture from the surface warm front combined with
surface heating and plenty of shear will still support
convection, and given the strong winds through the lower levels
and relatively cold airmass aloft, some isolated damaging winds
and hail will still be possible. Best potential for any stronger
storms will be from central to east-central Wisconsin. Heavy
rainfall will also be possible with any convection, with
probabilistic guidance continuing to paint out around 60-80%
chance for at least an inch of rain and some modest 10-25% chance
of two inches. There is a Marginal Risk of Excessive Rainfall
stretching across central to east-central Wisconsin and southwards
as well.

Rest of the forecast period...Another brief round of scattered
(20-30% chance) showers will be possible on Thursday, driven
primarily by strong surface heating. Convective support will be
relatively minimal, so expect impacts from any scattered showers
to be minimal. Behind this

The only chance for more widespread active weather would be Saturday
night into Sunday, when another larger system enters the Midwest
to western Great Lakes. However, as of this forecast cycle this
system tracks south of the area, which would keep much of the
convective potential to our south and may limit how much rain we
ultimately see. Still, will be something to keep an eye on if you
have plans to travel towards Illinois over the weekend.

&&

.AVIATION...for 06Z TAF Issuance
Issued at 957 PM CDT Mon Jun 15 2026

SCT showers and isolated storms remain possible through tonight,
though have opted to withhold any PROB30 mentions for thunder due
to low confidence. Brief gusty outflow winds and drops in vsbys
may accompany any showers or storms if they were to move over a
terminal. Otherwise, prevailing west/southwest winds will continue
to subside overnight with the loss of daytime mixing.

Cigs will continue to lower and thicken ahead of an approaching
cold front Tuesday morning, eventually bringing MVFR flying
conditions to the western sites by around 14 to 16Z. Another
round of scattered showers/storms will then be possible Tuesday
afternoon and evening.

&&

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

&&

$$

DISCUSSION.....Uhlmann
AVIATION.......Goodin

NWS GRB Office Area Forecast Discussion