314
FXUS63 KGRB 020507
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
1107 PM CST Sun Nov 1 2026

Updated aviation portion for 06Z TAF issuance

.KEY MESSAGES...

- Periods of rain, gusty winds, and a few rumbles of thunder from
  late this afternoon through Thursday, peaking tonight through
  Tuesday evening. Probabilities to reach or exceed 1 inch are
  65-95% north and west of the Fox Valley, and 40-60% in the Fox
  Valley east to Lake Michigan from Monday afternoon through
  Wednesday afternoon.

- Above normal temperatures continue through Thursday, falling to
  normal to end the week.

&&

.DISCUSSION...
Issued at 1047 PM CST Sun Nov 1 2026

Periods of Rain Through Thursday...Quiet and dry conditions remain
overnight with clouds increasing ahead of a developing low
pressure system, currently over the Central Plains. This system is
expected to bring periods of light to moderate rain, gusty winds,
and a few rumbles of thunder this afternoon/evening through
Thursday. Southerly flow will usher in well above normal PWATs of
around 1.5-1.6 inches (99th percentile of climatology) this
evening through Tuesday evening, when the biggest surge of
moisture is expected. PWATs and rain intensity decrease Tuesday
night through Thursday, as low-level winds gradually turn
westerly, cutting off Gulf moisture. A few rumbles of thunder from
elevated storms are possible at times, mainly on Tuesday, given a
couple hundred J/kg of MUCAPE, but strong/severe storms are not
expected.

Despite the prolonged period of rain this week, a complete washout
is not expected. However, drought stricken areas across northern WI
could see some relief as probabilities for 1 inch or more of rain
are 65-95% for locations north and west of the Fox Valley, with 40-
60% in the Fox Valley east to Lake Michigan late this afternoon
through Wednesday afternoon. The probability for 2 inches continues
to decreased slightly with NBM prob now forecasting 20-50% for
locations north and west of the Fox Valley. Additional periods of
light rain are expected after Wednesday afternoon through Thursday.
Dry conditions are expected to finally return by Friday, however,
another short-wave may bring periods of rain back to the area next
weekend.

Temperatures...Above normal temperatures are expected through
Thursday, falling to normal on Friday through the weekend (highs in
the upper 40s to low 50s) following the prolonged rainy system.
Tuesday will be the warmest day with highs in the mid to upper 60s,
but the cloud cover and rain may cause slightly lower temperatures.
A few sites may be near/set new record high minimum temperatures on
Tuesday, November 3.

&&

.AVIATION...for 06Z TAF Issuance
Issued at 1105 PM CST Sun Nov 1 2026

No significant changes to the previous forecast.  VFR conditions
with SCT to BKN mid and high level clouds are expected to prevail
across the region the start of the TAF period. Ceilings will
lower to MVFR from southwest to northeast between 12Z and 17Z Mon
ahead of an incoming low pressure system. Flying conditions will
then further deteriorate this afternoon as rounds of light to
moderate rain, gusty southeast winds, and IFR cigs overspread the
region. The poor flying conditions will likely linger at least
into Tuesday.

Southeast winds will gradually increase today with widespread gusts
20-25 kts by late afternoon. As winds aloft increase, strong low
level wind shear (south winds at 45-50 kts at 2 kft AGL) will
develop after 22Z Mon.

&&

.MARINE...
Issued at 1047 PM CST Sun Nov 1 2026

A slow moving low pressure system will move across the Great Lakes
tonight into Wednesday morning, bringing a prolonged period of gusty
south to southeast winds and large waves on the bay and Lake
Michigan. A Small Craft Advisory has been posted for the Lake
Michigan nearshore waters from this afternoon through Wednesday
evening. A few gale force gusts are possible Tuesday on Lake
Michigan. The Small Craft Advisory may need to be expanded to cover
the Bay as well.

Winds will shift to the north on Thursday, possibly gusting to
near 25 kts as the system departs to the east.

&&

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

&&

$$

DISCUSSION.....GK
AVIATION.......MPC
MARINE.........GK