188
FXUS63 KGRB 071811
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
111 PM CDT Tue Apr 7 2026

Forecast discussion for routine afternoon forecast issuance

.KEY MESSAGES...

- Light mixed precipitation may bring slippery roads to parts of
  central, north-central and far northeast WI late tonight into
  Wednesday morning. Moderate rain overspreads the region late
  Wednesday afternoon and evening.

- Strong south winds on Lake Michigan prompt the issuance of a
  Gale Warning Wednesday morning through late Wednesday evening.

- Potential is increasing for additional heavy rainfall late this
  weekend into early next week. Probabilities for 1 inch or more
  of precipitation are 60-75%, with a 20-45% probability of 2
  inches or more from this system.

- Minor flooding continues along a few rivers this week, with
  potential for more widespread flooding later next weekend into
  early next week.

&&

.DISCUSSION...
Issued at 111 PM CDT Tue Apr 7 2026

High clouds will increase this evening as high pressure moves off
to the east, allowing a robust 50-55knot low-level jet to move
through the western Great Lakes region. The low-level jet will
bring warm air advection as winds turn southerly and an area of
isentropic lift tracks through the area. The lift will bring a
wintry mix of snow, then changing to sleet, freezing rain and
eventually rain as warmer air arrives at the surface. This area of
precipitation will be a fairly narrow band and only last a few
hours; however, the timing of the precipitation could impact the
morning commute on Wednesday. Snow and sleet amounts should be
fairly light, on the order of a dusting to half inch. Freezing
rain could produce a light glaze of ice across central, north-
central, and northeast Wisconsin. While this wintry mix would
usually necessitate a Winter Weather Advisory, current thinking is
ground and road temperatures will be warm enough for the impacts
from any ice to be minimal, with most of the ice accumulations
expected on elevated surfaces or on bridges. Therefore, will
handle the event with Special Weather Statements as it moves
through the region as some slippery spots are anticipated, but a
widespread icy road threat is not anticipated.

A second round of moderate rainfall arrives with a cold frontal
passage and short-wave trough during the late afternoon in north-
central and central Wisconsin, and the evening across northeast
and east-central Wisconsin.

High pressure will bring a period of mainly dry weather late
Wednesday night through Saturday, with the exception of a 30-50%
chance of light precipitation over the southern half of the
forecast area Thursday night. This round of precipitation is up in
the air as there are some models that deal us a glancing blow or
keep much of the area dry; therefore, confidence in precipitation
Thursday night is still on the low side despite the higher POPs.

A prolonged period of more significant rainfall arrives Saturday
night into early next week, with deep southerly flow leading to
an influx of Gulf moisture. This rainfall could push totals for
the week to 1.5 to 2.5 inches in many areas. 72 hour probabilities
for rainfall for the back half of the weekend into early next
week currently stand at 60-75% for an inch or more with a 20-45%
chance of 2 inches or more during this period.

&&

.AVIATION...for 18Z TAF Issuance
Issued at 1150 AM CDT Tue Apr 7 2026

Expect VFR flying conditions through this evening, with only an
increase in high clouds. WAA on the nose of a 50 knot low-level
jet will generate a light mix of snow, sleet, freezing rain or
rain late tonight into early Wednesday. Conditions are expected to
drop to MVFR with the precipitation that moves through the
region. Increasing winds aloft will result in LLWS overnight.

Light and variable winds will become S-SE this afternoon, then
increase and become gusty late tonight into Wednesday.

&&

.HYDROLOGY...
Issued at 111 PM CDT Tue Apr 7 2026

Rivers that are in minor flooding continue to fall off the map
today as rivers slowly fall across the region. No rivers are
forecast to reach moderate flood stage this week. The saturated
conditions along with multiple chances for widespread
precipitation beginning tonight/Wednesday and lasting through
this weekend into early next week will result in some rivers
staying nearly steady, before they begin rising again this weekend
into early next week when potential for heavier precipitation is
expected due to an open Gulf and multiple stronger systems. At
this point, it appears a more substantial flooding threat could
develop. At the least, it appears multiple rivers could see minor
flooding. There will also be a renewed potential for areal
flooding (especially in poor drainage and low-lying areas) even
away from where the river flooding occurs.

&&

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

&&

$$

DISCUSSION.....Kurimski
AVIATION.......Kurimski
HYDROLOGY......Kurimski

NWS GRB Office Area Forecast Discussion