004 

FXUS63 KGRB 301733

AFDGRB



Area Forecast Discussion

National Weather Service Green Bay WI

1133 AM CST Tue Dec 30 2025



Updated aviation portion for 18Z TAF issuance



.KEY MESSAGES...



- A clipper system brings a round of fluffy snow today into early

  tonight. An inch or less is likely for most, with 1 to 2 inches

  expected in the Fox Valley, bayshore and lakeshore areas. Minor

  travel concerns are expected.



- An arctic cold front will bring additional light snow on

  Wednesday, with a dusting to a half inch anticipated most areas.

  A couple inches of snow will be possible in Vilas County due to

  lake-effect.



- Wind chills as cold as 15 to 25 below zero are possible New

  Years Eve night into Thursday morning.



&&



.DISCUSSION...

Issued at 324 AM CST Tue Dec 30 2025



Low clouds and flurries persisted over north central and far 

northeast WI early this morning, as mid-level clouds increased 

regionwide due to WAA ahead of an approaching clipper system.

The regional radar mosaic showed light snow developing over

eastern ND and northwest MN.



Clipper System Snow: WAA ahead of the approaching clipper will

generate patchy light snow or flurries across the area later this

morning, but snow should pick up a bit this afternoon as a short-

wave trough and LFQ of a 110 kt jet streak arrives. This system 

seems to get its act together as it moves into eastern WI, with a

more concentrated area of lift developing within the dendritic 

growth zone. Most areas should see a half inch to an inch of snow,

but the Fox Valley, bayshore and lakeshore areas could get 1 to 2

inches. This will produce slick roads, especially in eastern WI, 

for the evening commute.



Arctic Cold Front Snow: An arctic cold front will move into

northern WI late tonight, then drop south through the region

during the day on Wednesday. As this occurs, conditions will

become more favorable for lake-effect snow (NW winds and 

increasing instability over western Lake Superior) in NC WI, with 

accumulations of 1 to 3 inches possible in Vilas County. Despite 

the arrival of a dry arctic air mass, have opted to boost pops 

across the forecast area given fairly strong dynamics with the 

frontal passage, increasing FGEN, a short-wave and the LFQ of a 

135 kt jet streak. Outside of the lake-effect region, only 

expecting a dusting to a half inch of powder in most areas.



Brief Period of Cold: A fairly strong push of cold air arrives in

the wake of the arctic front, with H8 temps dropping to -18 to -23

C across the region later Wednesday into Wednesday night. The

combination of temperatures falling into the single digits below

zero (except near Lake Michigan) and persistent NW winds will

result in wind chills of 15 below to 25 below zero late Wednesday

night into Thursday morning. Wind Chill Advisories may eventually

be needed for roughly the northwest half of the forecast area.

Some moderation in H8 temperatures occurs Thursday into Thursday 

night, and cloud cover should prevent another big nighttime drop 

in temperatures, so wind chills should not be as low Thursday 

night into Friday morning.



Rest of the Forecast: No significant precipitation events are

expected for the rest of the extended forecast period. After the

brief shot of arctic air, a gradual moderate in temperatures is

expected, with highs reaching the 20s by Sunday/Monday.



&&



.AVIATION...for 18Z TAF Issuance

Issued at 1133 AM CST Tue Dec 30 2025



VFR cigs were ubiquitous across the region late this morning, with

some MVFR cigs across northern Door County. Upstream, an incoming

Alberta Clipper was bringing an area of light snow and MVFR cigs 

across northwest Wisconsin.



Light snow will overspread the region this afternoon, with mainly

MVFR ceilings/vsbys. Potentially more significant snow should 

impact the region from mid-afternoon through early evening, with 

periods of IFR vsbys expected. The snow should taper off from west

to east in the evening, though some lake-effect snow could 

persist in far NC WI. Additional snow is expected on Wednesday as

an Arctic cold front sinks south through the region.



Winds will be from the W-NW with speeds of 10 knots or less

through tonight. Winds then increase to 10 to 20 knots with the

Arctic front Wednesday from the NW.



&&



.GRB WATCHES/WARNINGS/ADVISORIES...

None.



&&



$$



DISCUSSION.....Kieckbusch

AVIATION.......Kurimski