NWS-Green Bay Forecast Discussion

						FXUS63 KGRB 281150
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
550 AM CST Sat Feb 28 2026

Updated aviation portion for 12Z TAF issuance

.KEY MESSAGES...

- A band of snow (50-80% chance) to move across the southern half
  of the area today. Snowfall totals between 0.5 and 2.5 inches
  are expected for most locations, mainly south of Highway 29.

- Within this band of snow, a narrow 2-3 county wide band of
  heavier snow with 3"+ is expected. Current indications have this
  heavier band just south of the area.

- Below normal temps this weekend, then a slow but steady warming
  trend for next week as a more spring-like pattern sets up,
  resulting in at least a couple chances for rain or snow.

&&

.DISCUSSION...
Issued at 206 AM CST Sat Feb 28 2026

Today's Snow Chances & Narrow Band of Heavier Snow: The
combination of increasing isentropic ascent, a coupled upper
jet, and 850-600mb FGEN will allow for a long, narrow band of snow
to continue to expand across the northern Plains and Great Lakes
today. All eyes will be on exactly where the 2-3 county wide band
will ultimately set up, as these bands are notorious at making
small, but impactful shifts. High-res models have a decent handle
on the band which is currently across MT/SD/ND/MN, but small
differences remain as it shifts eastward. High-res model consensus
has improved over the last few runs, with the previous outlying
HRRR shifting south/west. This makes sense with the dry air
advecting into the region from the north. So confidence has
increased that the heaviest area of snow will stay just to our
south. But any minor shift to the north will bring the northern
edge toward the Hwy 10 corridor. On the flip side, any southward
shift, with the dry air winning, would keep totals under an inch
with many spots not seeing any snow.

Have continued to use a model blend, with 1.0-2.5" of snow south
of Hwy 10 (current probabilities for 2"+ are 20-40% from Wisconsin
Rapids to Oshkosh) and under an inch elsewhere. Any 3"+ totals
would be confined to the stronger FGEN band, along with snow rates
around 1-1.5"/hr. Have delayed the onset of the snow a little, as
the drier air at the surface will take some time to overcome,
with most of the snow holding off until after noon. Still expect a
pretty sharp cut-off on the northern edge, with some weak forcing
north of the main FGEN band which could produce some very light
snow/flurries. Within the heavier band, the stronger lift within
the DGZ will produce snow ratios of around 20-25:1, leading to the
higher localized totals. Outside the heavier band, the snow will
still be on the fluffy side, but closer to 15:1. The
blowing/drifting snow potential looks very low as winds will
remain under 15 mph most of today and tonight. Will continue to
monitor upstream ob trends and the latest guidance on where the
band will track. As the FGEN and broad lift weakens/exits this
evening, snow chances will end.

One other small wrinkle in the forecast could be a lake effect
snow band over far eastern WI this evening into tonight. While
surface winds could shift more to the NNE, 850mb winds look stay
NW or N, which should keep any snow band just offshore.

Off & On Rain/Snow Chances Next Week: As the flow turns zonal,
there will be periodic chances for precip through the week. First
system arrives Monday night into Tuesday, with 40-60% chances for
mixed precip. Current temp profiles favor mainly wet snow, with
some impactful snow possible, but the degree of phases is in
question and will determine just how strong this system will be.
Another system is forecast to arrive later in the week. With
temps moderating, mainly rain is expected, but a little snow may
mix in over the north at times, especially at night.

Temps Warming Into Next Week: Below normal temps are expected this
weekend, with highs in the teens and 20s, as northwest flow
ushers in a batch of arctic air. Some below zero winds chills are
expected at night. Temps then will be on a slow but steady rise
next week as a pattern change occurs over much of the CONUS. The
more zonal flow will allow for Pacific modified air to spread into
the Great Lakes for most of the week. Highs look to be in the 40s
and 50s, with some 60s not too far to the south by the end of the
week. The warmer temps, along with the rain, will lead to a
shrinking snowpack, with most/all of the snow likely melting
across central and eastern WI. North-central WI has a foot or two
of snow on the ground, so that will be slower to melt. Some minor
hydro issues could arise if/where the largest snowpack exists, but
hopefully this pattern will allow for a gradual melt. The ice jam
threat will also increase for those rivers that are still frozen.

&&

.AVIATION...for 12Z TAF Issuance
Issued at 550 AM CST Sat Feb 28 2026

Other than a few MVFR ceilings/vsbys and a few flurries at RHI
and across north-central WI, VFR conditions are expected this
morning with mid-clouds increasing across the region. Clouds will
lower later this morning and afternoon, with a band of snow
moving across the southern half of the state later this morning
into early this evening. Models not in good agreement on how low
clouds will get, ranging from VFR to IFR. Trends continue to point
at the heaviest snow staying to the south as dry air at the
surface will be tough to overcome the further north you go;
however, still some disagreement on if another area of mainly
light snow will develop further north. Have leaned towards higher
ceilings/vsbys, but upstream trends will need to be monitored for
lower conditions, especially at ATW/MTW. In addition, if the
heavier snowband shifts a little north late this afternoon,
ATW/MTW would see a period of IFR or possibly brief LIFR
conditions. Chances of this occurring are under 20% so will not
include. Conditions look to become VFR overnight into Sunday
morning.

Gusts to around 15 kts will remain possible through ~14z, then
winds will generally remain under 10 kts through the TAF period,
shifting from the N this morning to the N/NNE this afternoon into
tonight.

&&

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

&&

$$

DISCUSSION.....Bersch
AVIATION.......Bersch