961
FXUS63 KGRB 260415
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
1115 PM CDT Tue Aug 25 2026

Updated aviation portion for 06Z TAF issuance

.KEY MESSAGES...

- Scattered showers and thunderstorms (40-60%) are expected
  through late tonight.

- Gusty south/southwest winds will generate hazardous conditions
  for small craft and dangerous swimming conditions along Lake
  Michigan this evening through Wednesday morning.

- Scattered thunderstorms are also possible on Wednesday. Some
  of the strongest thunderstorms will produce wind gusts to
  45 mph, small hail and brief heavy rain.

- Next chance for unsettled weather arrives this weekend.

&&

.DISCUSSION...
Issued at 154 PM CDT Tue Aug 25 2026

Skies were partly to mostly cloudy across the region this
afternoon with temperatures in the 70s. Isolated to scattered
showers and thunderstorms developed in response to 850mb warm
advection ahead of a weak cold front across northwest and west-
central WI. Some of this activity will make it into central and
north-central WI towards 00z Wednesday. Meanwhile, a cold front
across Minnesota will trigger additional shower and thunderstorm
activity that should move into central and north-central WI during
the mid to late evening hours, then across northeast WI after
05z. Some of the stronger storms across central and north-central
WI could be strong or severe with damaging wind gusts to 60 mph,
hail up to one inch in diameter and brief heavy rain. Bufkit
soundings indicated 500 to 1,000 J/KG and decent shear values
around 30 knots. The Storm Prediction Center Day 1 Outlook has a
Marginal Risk (Level 1 of 5) west of a Wisconsin Rapids to Land O`
Lakes line.

There will be a break in the showers and storms overnight.
Meanwhile, an upper trough will swing across the area on
Wednesday. Daytime heating combined with enough CAPE would support
scattered thunderstorms over the northeast portion of the state.
Some of the storms will be capable of producing small hail, gusty
winds to 45 mph and brief heavy rain. Inverted V sounding would
support gusty winds.

Dry conditions expected Wednesday night through Friday as high
pressure moves across the region. The next chance of storms
arrives Friday night into Saturday with chances of storms
lingering through the weekend. There is the possibility of a
few thunderstorm complexes over the weekend, but the details
on location and timing are uncertain at this time. Dry conditions
return Monday and Tuesday. High temperatures during the period
should be at or slightly above normal.

&&

.AVIATION...for 06Z TAF Issuance
Issued at 1114 PM CDT Tue Aug 25 2026

Isolated showers and maybe a rumble of thunder impact eastern TAF
sites through 06z. More concentrated area of showers and a few
storms moves across central and north-central WI, and lingering
as late as 10-12z for eastern WI. Scattered showers or storms may
re-develop on Wednesday late morning through the afternoon,
especially north and northeast WI. Have introduced a PROB30 for
showers at RHI and GRB for now. Other story will be VFR cigs
deteriorating to MVFR (local IFR) cigs late tonight into
Wednesday morning. Improvement to VFR cigs will occur in the
afternoon. Cigs will gradually scatter out on Wednesday evening.

South-southwest winds will gust over 15 kts at times overnight. On
Wednesday, expect gusty winds to 15-20 kts at all the TAF sites
as winds shift to the west-northwest behind cold front. Light
northwest winds will persist on Wednesday evening.

&&

.MARINE...
Issued at 154 PM CDT Tue Aug 25 2026

A period of persistent south/southwest winds is expected this
afternoon into Wednesday. Winds will gust to 25 kts, with waves
building to 2 to 4 ft with some 5 foot waves possible mainly along
the Lake Michigan nearshore waters. As a result, a Small Craft
Advisory remains in effect from 6 PM this evening to 4 AM
Wednesday from Sheboygan to Sturgeon Bay, and 8 PM this evening to
11 AM Wednesday from Sturgeon Bay to Washington Island. On the
bay, These conditions will also result in a high swim risk at
Lake Michigan beaches. Beach Hazards Statements have been issued
for Manitowoc, Kewaunee, and Door County. Meanwhile, A Small Craft
should exercise caution on the bay tonight through mid-morning on
Wednesday.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Beach Hazards Statement until 11 AM CDT Wednesday for WIZ022.

Beach Hazards Statement until 4 AM CDT Wednesday for WIZ040-050.
&&

$$

DISCUSSION.....Eckberg
AVIATION.......JLA
MARINE.........Eckberg

NWS GRB Office Area Forecast Discussion