522
FXUS63 KGRB 222338
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
538 PM CST Fri Nov 22 2024

Updated aviation portion for 00Z TAF issuance

.KEY MESSAGES...

- The chance for light rain and snow Sunday night and Monday
  night have increased. There is a 40-50% chance of getting at
  least 1 inch of snow in north-central WI, and a 20% chance to
  get at least 2 inches of snow.

- A cooling trend is forecast over the next week. Highs in the 30s
  and 40s through the weekend will cool into the 20s and 30s by
  the middle of next week.

&&

.DISCUSSION...
Issued at 316 PM CST Fri Nov 22 2024

Short Term...Tonight and Saturday

Quiet conditions are expected to dominate the region for the
short term period through Saturday evening.

Drizzle remains possible at times this afternoon across north-
central Wisconsin near the Upper Peninsula border but should taper
off by the evening. The low level moisture will keep the rest of
the area dry, but cloudy conditions are likely to persist well
into the overnight hours. Low temperatures under the cloudy skies
are expected to range from the middle 20s in the northwoods to the
middle 30s near the Fox Valley.

Saturday, low level moisture will decrease in the late morning
hours, which does bring some hope for at least partial clearing in
the cloud cover aloft, which could bring a few pockets of sunshine
by the early afternoon. However, warm air advection will also be
on the increase by this time, which may offset the decreased low
level clouds and bring back some upper cloud cover, keeping most
of the region cloudy. Temperatures on Saturday will be near
normal, ranging from the middle 30s in the northwoods to the lower
40s near the Fox Valley.

Long Term...Saturday Night Through Friday

Focus is on precip chances Sunday night through Monday night, and
temperature trends.

Precip...Shortwave energy and associated surface low are likely to
bring at least some precip to the area Sunday night into Monday
night. Latest model runs have trended a little higher, in both
probability of precip (PoP) and QPF. This has also resulted in higher
snowfall probabilities, particularly across northern Wisconsin.
Much of north-central WI has a 40-50% chance of receiving 1" or
more snow (higher in northern Vilas Co), and ~20% chance of
getting 2" or more of snow. East-central WI is still expected to
get primarily rain, but some snow could mix in as far east as the
Fox Valley.

Timing wise, mid-levels still take several hours to saturate, so
while some light precip may begin Sunday evening, it looks like
most places will not see anything reaching the ground until after
midnight.

Occasional snow remains in the forecast from Tue-Fri with
lingering cyclonic flow. This is primarily across northern and
eastern WI which is closer to the departing low and is in the lake
effect snow region from Lake Superior.

Temperatures...A pattern shift will allow cooler air to arrive
Tuesday, with temperatures trending below normal through the
Thanksgiving holiday and into next weekend. This will average
highs in the mid 20s to mid 30s; and lows in the teens to low 20s.

&&

.AVIATION...for 00Z TAF Issuance
Issued at 538 PM CST Fri Nov 22 2024

A low cloud deck will remain in place across the region through
the overnight hours, keeping MVFR cigs in place for most sites.
Ceilings could dip to IFR for most of the TAF sites at times as
clouds lower a bit, mainly across central and north-central
Wisconsin. Some patchy fog is possible north of Rhinelander, but
not currently expected to make it into the RHI vicinity. Finally,
some improvement in sky cover will arrive from the southwest
Saturday morning, gradually lifting cigs to MVFR and possibly low
VFR by Saturday afternoon.

&&

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

&&

$$

DISCUSSION.....Uhlmann/KLJ
AVIATION.......Kurimski