464
FXUS63 KGRB 142302
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
502 PM CST Sun Dec 14 2025

Updated aviation portion for 00Z TAF issuance

.KEY MESSAGES...

- Wind chill readings of -5 to -15 should continue tonight into
  Monday morning.

- A clipper system will bring a chance of light snow (20-60%) to
  portions of northeast WI late tonight into early Monday morning,
  generally east of Land O` Lakes to Green Bay to Chilton line.
  Snowfall amounts up to an inch and a half are possible.

- A strong winter storm moving across the Upper Midwest will bring
  a variety of impacts Wednesday night into Friday. Hazardous
  travel is likely at times as this system will bring rain, snow
  or a wintry mix to the area along with areas of fog at times.

- Temperatures above freezing are expected to turn sharply colder
  on Thursday, falling below freezing which may result in roads, bridges
  and sidewalks to become icy.

- Strong winds over 40 mph are possible on Thursday and Thursday
  night, which may result in isolated power outages.

&&

.DISCUSSION...
Issued at 254 PM CST Sun Dec 14 2025

Three systems to deal with during the period. A clipper system is
expected to move across the region later tonight into early
Monday morning. This system will clip northeast Wisconsin with the
chances of light snow (20-60%) east of a Land O` Lakes to Green
Bay to Chilton line. Highest chances for snow across northern Door
County. Snowfall amounts under an inch are expected, with amounts
up to one and a half inches north of Sturgeon Bay. Wind chill
readings tonight will continue in the -5 to -15 degree range
through the night into early Monday morning, despite temperatures
slowly rising overnight as winds will be on the increase.
Temperatures moderate some on Monday with highs in the upper teens
to middle 20s.

The moderation in temperatures continue on Tuesday with highs
warming into the 30s. This will be the first day above freezing
this month. At Green Bay, the 15 consecutive days below freezing
to start the month is 4th longest streak on record. The record is
25 straight days below freezing set in 1919. The milder temperatures
continue on Wednesday, although a few degrees cooler. At some
point, the dewpoints will be on the rise later Wednesday into
Thursday, which will likely result in fog at times. The fog
may be locally dense.

A strong winter storm is expected to move across the region
Thursday into Thursday night. The storm track will be north of
the area, thus this will limit precipitation amounts with the
main cold front. Wrap around moisture, along with cold northerly
will bring continued chances of snow Thursday night into Friday.
850mb temperatures are expected to climb above freezing Wednesday
into Thursday ahead of the main cold front. Rain, snow or a wintry
mix is possible along and ahead of the cold front, then should
turn over to snow from west to east on Thursday as colder air
rushes in. A check of the Wisconet network, 2" ground temperatures
are a degrees or two either side of the freezing mark. The deep
snow cover has insulted the top soil from falling farther below
freezing. However, the question is what the 2" ground temperatures
are at local roads and highways. Even if air temperatures are a
few degrees above freezing, the cold ground could cause icy spots
especially Wednesday night. Will need to monitor and may need to
add some more freezing rain in the coming days. As the front moves
across the region on Thursday, temperatures should plummet below
freezing which may cause roads, bridges and sidewalks to become
icy. Strong winds over 40 mph are possible, especially Thursday
and Thursday night that may result in isolated power outages.

Another clipper system bring a chance of light snow Friday
afternoon or Friday night, otherwise tranquil conditions
expected next weekend. Saturday will be the warmer day
of the weekend.

&&

.AVIATION...for 00Z TAF Issuance
Issued at 444 PM CST Sun Dec 14 2025

VFR conditions will prevail tonight across much of the area. The
next clipper system will bring a chance of light snow to portions
of northeast WI late tonight into early Monday morning, generally
east of a line from KLNL to KMTW. A little uncertainty if snow
would make it to KGRB/KMTW; therefore, used a prob 30 group to
cover the possibility of some light snow in these locations. Late
this evening into early Monday morning, low level wind shear will
develop from 220-240 degrees at 35 to 45 knots. MVFR CIGS and
VSBYs will be possible in the areas of snow.

&&

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

&&

$$

DISCUSSION.....Eckberg
AVIATION.......Kurimski

NWS GRB Office Area Forecast Discussion