FXUS63 KGRB 062022

AFDGRB



Area Forecast Discussion

National Weather Service Green Bay WI

322 PM CDT Sun Apr 6 2025



Forecast discussion for routine afternoon forecast 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 18Z TAF Issuance

Issued at 1240 PM CDT Sun Apr 6 2025



Daytime heating and an approaching cold front were generating an 

area of high-based stratocumulus across northern WI and the Upper 

peninsula of MI early this afternoon. No precipitation was noted 

at this point, as very dry low-level air was in place. 



VFR conditions will prevail through this afternoon, with just a

few light showers possible in far northern WI late in the day.

The cold front will sweep south across the region this evening

accompanied by a band of rain and snow showers, which will quickly

change to all snow. Flight conditions should drop to MVFR in most

areas tonight, with some IFR VSBYs expected in parts of NC/far NE

WI. The precipitation should arrive in KRHI around 01Z, reaching 

KAUW around 03Z, KGRB/KATW around 05z, and KMTW around 06z. 

Snowfall amounts will range from a dusting to an inch in most

areas, with locally higher amounts in the far north and northeast.

The steadier snow should end late tonight, though a few snow

showers or flurries could be seen from time to time through 

Monday. Flight conditions should return to VFR in most areas as 

drier air arrives Monday morning.



Gust west-southwest winds will occur this afternoon, ahead of the

cold front. As the front moves through, winds will shift sharply

to the NW-N and gust to around 25 kts. The blustery conditions

will persist into Monday. A few small areas of LLWS are 

anticipated starting late this evening and continuing into early 

Monday morning.



&&



.GRB WATCHES/WARNINGS/ADVISORIES...

None.



&&



$$



DISCUSSION.....Kieckbusch

AVIATION.......Kieckbusch