Expires:No;;897678
FXUS63 KGRB 070323
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
1023 PM CDT Sun Apr 6 2025

Updated aviation portion for 06Z TAF issuance

.KEY MESSAGES...

- Water levels will remain elevated on area rivers and streams 
  into next week due to runoff from recent rainfall. Minor 
  flooding is possible at a few locations.

- Accumulating snow is expected most areas tonight into Monday
  morning, along with locally hazardous travel conditions. Most
  locations will see a dusting to an inch of snow, with higher
  amounts to around 2 inches in the far north.

&&

.DISCUSSION...
Issued at 322 PM CDT Sun Apr 6 2025

A cold front was dropping south through Lake Superior and the U.P.
of Michigan this afternoon. The approach of the front, combined
with daytime heating, was generating high-based stratocumulus
clouds across NC/NE WI, but no precipitation was occurring due
to very dry air in the lower atmosphere.

A developing low pressure system just northeast Duluth is 
expected to move through the region tonight, accompanied by a 
strong cold front. This system looks fairly dynamic, with a 
potent short-wave trough, LFQ of an upper jet and strong 
frontogenetic forcing. However, given the initially dry and
mild air ahead of the front, short duration of deep saturation/
strong lift, and most of the lift occurring below the Dendritic 
Growth Zone, have lowered snowfall amounts a bit compared to 
recent forecasts. The exception is across far northern WI, where 
lake-enhancement should help accumulations. Current thinking is 
that accumulations will range from a dusting to an inch in most
areas, with 1-3 inches in far northern WI. Most of the snow
should be done by late tonight, so the morning commute may not be
significantly impacted. Locally slippery conditions are still
anticipated late tonight into early Monday, especially where 
more significant accumulations occur. There will be a continued 
chance of lake-effect snow showers in NC WI on Monday, and 
potential for isolated to scattered flurries or very light snow 
showers due to high-based convective development in the 
afternoon.

Winds will also increase as the low departs later tonight into 
Monday, with NW-N winds gusting to 25 to 35 mph, strongest in the 
Fox Valley and lakeshore areas. A Small Craft Advisory has been 
issued for tonight through Monday evening. 

After a brief dry period Monday night through Tuesday night, a
chance of mixed rain/snow returns Wednesday into Thursday. Models
continue to show the more significant QPF staying south of the 
forecast area, with the best chances occurring over our southern 
counties. Mainly dry and milder conditions are expected for the 
weekend as upper level ridging and southerly surface winds set up
over the western Great Lakes.

&&

.AVIATION...for 06Z TAF Issuance
Issued at 1020 PM CDT Sun Apr 6 2025

A strong cold front will continue to sweep across the region
tonight, reaching central and east-central WI within a few hours 
either side of 06z Monday. Precipitation should be mainly in the 
form of snow, however it is expected to start as rain for about an
hour or two before changing over to snow. Temperatures will fall 
below freezing tonight, so icy spots are possible on runways 
overnight. CIGS will drop into the MVFR category as the snow moves
across the region, then should lift back into the VFR category as
the band of steadier snow moves out of the area overnight. 
Blustery northerly winds should be expected on Monday with gusts 
to around 30 knots possible, especially across eastern Wisconsin.
Skies will turn clear with diminishing winds Monday evening. 

&&

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

&&

$$

DISCUSSION.....Kieckbusch
AVIATION.......Eckberg