NWS-Green Bay Forecast Discussion
FXUS63 KGRB 162006
AFDGRB
Area Forecast Discussion
National Weather Service Green Bay WI
206 PM CST Fri Jan 16 2026
Forecast discussion for routine afternoon forecast issuance
.KEY MESSAGES...
- Light snow to continue over most of the area through Saturday
morning. Light to moderate lake effect snow will result in
greater snowfall amounts in Vilas County (4 to 6"), where a
Winter Weather Advisory is in effect until noon on Saturday.
- Bitter cold arrives this weekend into early next week, with a
broad 60-100% chance of wind chills colder than -20F both
Monday and Tuesday mornings.
- Active pattern remains in place through next week, with several
clipper systems bringing additional opportunities for
accumulating snow.
&&
.DISCUSSION...
Issued at 109 PM CST Fri Jan 16 2026
Snow chances... Radar shows that the initial round of snow has
exited the area, with subsidence behind the line resulting in a
lull in snow activity for some. However, comma head returns have
begun to fill back in this afternoon as additional shortwave
energy pivots through the western Great Lakes. CAMs start to show
the snow squall parameter flagging within these returns due to
marginal lift and decent saturation, though remain pessimistic on
this front given a lack of better instability, a strong arctic
front, or focused mid-level FGEN. Could certainly see some
convective snow showers, though likely not any organized squalls.
Regardless, biggest change to this forecast package revolves
around lake effect potential in the typical snowbelts across far
north-central Wisconsin as winds already begin to take on a more
northwesterly component along the back edge of the departing
surface low. Seeing several ingredients coming together for at
least a low-end lake effect event, namely as DGZ heights increase
to around 6 to 7k ft and delta Ts hit the sweet spot between 13
and 15C. As such, have opted to increase both PoPs and QPF in the
northwest snow belts, resulting in a solid 3 to 5 inches of total
snow across Vilas due to effective dendrite production. Some CAMs
go so far as to hint at the possibility of a mesoscale banding
feature developing, which would significantly boost snowfall
amounts were it to materialize. For the time being, have gone with
a Winter Weather Advisory for Vilas through 18Z Saturday, though
this will continue to be monitored.
Active pattern refuses to let up through the end of next week as
the 500 mb wave train proceeds at full steam ahead. We will be
afforded a brief break in precip late Saturday into early Sunday
before our next clipper system makes an appearance later Sunday
morning. Widespread light snow will once again be possible, though
far north-central Wisconsin will once again receive the brunt of
the snow. Yet another clipper system then arrives this week, with
the current trajectory looking to bring more impactful snowfall to
the rest of the forecast area.
Temperatures... Forecast concerns for the extended shift to the
arrival of arctic air this weekend into early next week as an
anomalously cold 850 mb airmass (nearing absolute min relative to
climo) settles over the Great Lakes. With high temperatures
failing to meet zero degrees at many locations and a
strong/consistent signal for at least 40 knot winds at 850 mb,
wind chills are progged to plummet to between 15 and 25 degrees
below zero at most locations, colder further west. The LREF grand
ensemble currently shows a broad 60 to 100% probability of lower
than -25F wind chills early Monday and Tuesday mornings, which is
heavily influenced by the high- performing ECMWF. As such, it
currently looks pretty slam dunk for cold weather headlines early
next week, especially as long-range guidance continues to trend
colder. Temperatures then moderate slightly mid- week as another
clipper system steers the core of the colder air off to the east.
&&
.AVIATION...for 18Z TAF Issuance
Issued at 1139 AM CST Fri Jan 16 2026
Initial round of snow has exited to the east late this morning,
leaving a low MVFR/IFR stratus deck and a lull in snow activity
in its wake. Light to moderate lake effect snow is set to continue
in/near RHI through the end of the TAF period due to sustained
northwest winds, with light snow filling back in elsewhere later
this afternoon and evening. For ground operations, an additional 1
to 2" of snow is expected at most terminals, with 2 to 4 across
north-central WI. Periodic light snow and MVFR/IFR conditions
will persist through Saturday morning, though confidence remains
low regarding the timing of category changes. Vsby reductions to
IFR will be possible within areas of heavier snow, especially
across the western sites. Winds will be predominantly out of the
northwest, with surface gusts between 15 and 20 knots.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until noon CST Saturday for WIZ005.
&&
$$
DISCUSSION.....Goodin
AVIATION.......Goodin