806
FXUS63 KGRB 232300
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
500 PM CST Sat Nov 23 2024

Updated aviation portion for 00Z TAF issuance

.KEY MESSAGES...

- The chances for light rain and snow from Sunday night through
  Monday night have increased. There is a 40-50% chance of getting
  at least 1 inch of snow in north-central WI, and a 30% chance
  to get at least 2 inches of snow.

- Light lake effect snow at times over far north-central Wisconsin
  mid to late next week. Only minor accumulations are expected.

- A cooling trend takes hold for the coming week. Highs in the 30s
  and 40s into Monday will cool into the 20s to 30s by the middle
  of the week, and into the 20s across the entire area by next
  weekend.

&&

.DISCUSSION...
Issued at 320 PM CST Sat Nov 23 2024

Short Term...Tonight and Sunday

Main focus for the remainder of today is cloud trends. Current
satellite imagery shows partial clearing across northern WI, while the
rest of the region remains under a blanket of mid-level clouds.
These clouds are streaming in in advance of an upper trough that is
forecast to arrive to the region tomorrow. Radar has picked up a few
weak echos early this afternoon across central WI as weak
frontogenesis is driving areas of virga. However, area web-cams have
shown no signs of any precipitation reaching the region.

A weak ridge sliding over the region overnight will keep the dry
conditions around through Sunday morning. Warm air advection ahead
of the aforementioned upper trough may produce scatter areas of
drizzle beginning Sunday afternoon, however, forecast soundings are
split as to if any precipitation will  make it to the ground. NAM
soundings continue to be the most aggressive with sufficient
saturation taking place during the afternoon to get areas of
drizzle, while RAP soundings are slower to saturate resulting in a
later onset of any precipitation. Regardless do not expect any
impacts through Sunday afternoon. Precipitation chances do increase
Sunday evening as does the chance for accumulating across northern
WI.

Long Term...Sunday Night Through Saturday

A surface low moving from Missouri to Lake Huron will bring some light
rain and snow to the region Sunday night through Monday evening. Most
of it will fall as rain Sunday night, but the rain should change to
snow across north central Wisconsin Monday before it diminishes Monday
evening. An inch or two looks likely there with not much elsewhere.

Winter will finally begin to arrive during the middle of next week,
as the medium range models show an upper ridge begin to build along
the west coast, and a trough over central Canada and the Great Lakes
region. Temperatures are forecast to be below normal by the end of
next week, with subzero wind chills possible Friday and Saturday night.

A surface low moving from Oklahoma to the Ohio Valley looks like
it could bring some light snow to southern Wisconsin Wednesday
night, but otherwise the northwest upper flow will result in dry
weather Wednesday through Saturday outside of some light lake
effect snow in Vilas county.

&&

.AVIATION...for 00Z TAF Issuance
Issued at 500 PM CST Sat Nov 23 2024

High and mid clouds are expected across the area tonight as they
stream in from the west. Some MVFR stratus will be possible this
evening across the far north with northwesterly flow. VFR
conditions will continue into Sunday with thickening and lowering
clouds throughout the afternoon. Lower CIGs and precipitation is
expected to hold off until Sunday evening as a surface trough
tracks through the area. Light surface winds below 10 knots are
expected during the TAF period.

&&

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

&&

$$

DISCUSSION.....GK/RDM
AVIATION.......Kurimski