022
FXUS63 KGRB 191830
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
130 PM CDT Tue May 19 2026

Forecast discussion for routine afternoon forecast issuance

.KEY MESSAGES...

- Frost or freeze headlines may be needed Wednesday night as lows
  fall into the low to mid 30s over the Northwoods.

- Below normal temperatures continue throughout the week, warming
  back up during the weekend.

- Scattered showers (30 to 60% chance) arrive Friday afternoon,
  lasting through Saturday.

&&

.DISCUSSION...
Issued at 1246 PM CDT Tue May 19 2026

GOES imagery and current obs show the cold front over eastern
Wisconsin as of this afternoon, with winds having largely shifted
to the northwest in its wake. Shower activity associated with the
front has begun to erode as drier air feeds in from high pressure
to the northwest. However, isolated showers will remain possible
through this evening due to steepening lapse rates within CAA
regime, though thunder chances will be little to none as any
daytime instability wanes.

Rain chances... Next chance (30 to 60%) for scattered showers
arrives Friday afternoon in tandem with decent shortwave energy,
lasting through much of Saturday. Moisture influx during this
time will be modest as we set up under marginal return flow, with
PWATs approaching one inch Friday evening. However, most
instability looks to remain holed up to our south in proximity to
the warm front, resulting in little to no severe weather
potential. Furthermore, lack of upper-level dynamics and surface
forcing mechanism would suggest very little thunder potential in
general. Synoptic flow then flattens out early next week before
ridging eventually builds over much of the eastern CONUS, keeping
us mostly dry through the middle of next week.

Temperatures... Below normal post-FROPA temperatures persist
through the weekend, with highs struggling to reach 60 degrees in
some areas through the end of the work week. As high pressure
sits and spins overhead, frost/freeze headlines may be needed at
times as lows dip down into the low to mid 30s. Current thinking
is that Wednesday night would be the better setup for frost
development over the Northwoods due to light winds and windows
for clearing. Tonight`s frost potential seems more marginal under
mostly overcast skies, and would be confined mainly to Vilas
county regardless. As such, have opted against a Frost Advisory
for tonight. Highs then gradually moderate back to near normal by
the end of the weekend and into early next week.

&&

.AVIATION...for 18Z TAF Issuance
Issued at 1123 AM CDT Tue May 19 2026

MVFR stratus deck has persisted over most of the forecast area
this afternoon as the cold front continues to progress to the
east. Downsloping northwest winds may help scatter out some of the
lower clouds later this afternoon and evening, with GRB, ATW, and
MTW expected to lift to VFR within the next few hours. BKN MVFR
cigs will likely stick around in/near RHI for the majority of the
TAF period, though windows for improvement to VFR will be
possible.

Winds have already shifted to the west/northwest as of this
afternoon, with the east-central sites expected to shift within
the next hour or two. Gusts between 20 and 25 knots will be
possible through this afternoon, before winds subside this evening
and overnight with the loss of daytime mixing.

&&

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

&&

$$

DISCUSSION.....Goodin
AVIATION.......Goodin

NWS GRB Office Area Forecast Discussion