Area Forecast Discussion
Issued by NWS Green Bay, WI

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39
000
FXUS63 KGRB 171702
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
1202 PM CDT WED AUG 17 2016

Updated aviation portion for 18Z TAF issuance

.SHORT TERM...Today...Tonight...and Thursday
Issued at 343 AM CDT Wed Aug 17 2016

Doppler radar and water vapor satellite imagery show a shortwave
currently tracking through northeast Wisconsin early this morning.
This feature will provide a few more hours of showers and
thunderstorms before a lull in the action later this morning.
Another weak shortwave will then track through the western Great
Lakes later this afternoon and this evening, providing the chance,
albeit smaller, for additional showers and thunderstorms. This
shortwave will take advantage of 1000 to 1500 J/kg of MUCAPE,
however the shortwave itself will be fairly weak along with a very
weak wind field depicted on model soundings, therefore severe
weather is not anticipated with the convection today or tonight.

Rain chances will diminish later tonight as the aforementioned
second shortwave tracks east, leaving partially clearing skies in
its wake. Light winds and breaks in the clouds will likely lead to
some fog development later tonight, especially across areas that
get rain later today and this evening. The region will be in
between systems on Wednesday as a low pressure system develops
across the upper Mississippi Valley. Convection on Thursday is
expected to remain to the west, however a continued warm airmass
will once again allow high temperatures to soar well into the 80s.

.LONG TERM...Thursday Night Through Tuesday
Issued at 343 AM CDT Wed Aug 17 2016

The main forecast concern continues to be the precipitation potential
late this week into the weekend.

A mid level trough is forecast to amplify over then central CONUS
as a cold front moves across the region. This will bring a chance
for thunderstorms as the front approaches, and then passes
through, the forecast area. The chance for showers and storms
should arrive in central Wisconsin Thursday evening and spread
across the east later in the night. Models were showing a surface
low moving along the cold front from the Plains toward Wisconsin.
This will help to keep a chance for thunderstorms going through
Saturday night, and some showers remain possible on Sunday as the
low passes southeast of the forecast area.

Severe storm potential remains unclear, though the SPC day 2
(18/12Z - 19/12Z) outlook showed a marginal risk of severe storms
across part of central Wisconsin. Expect much warmer than normal
highs on Friday, before cooler air moves in with the cold front
and associated clouds and rain.
&&

.AVIATION...for 18Z TAF Issuance
Issued at 1201 PM CDT Wed Aug 17 2016

Isolated showers are again possible this afternoon though should not
be as widespread as yesterday.  Greater concern revolves around fog
potential late tonight.  Low temps are forecasted to fall below the
crossover temp by a degree or two early overnight.  With little
change in the airmass and recent rainfall, this should lead to
patchy to areas of fog developing.  Think vsbys should bottom in the
1 to 3 miles at most locations except for those low lying areas or
cold spots, like RHI and CWA where vsbys should fall to 1/2 to
3/4SM. Once the fog burns off, good flying weather will resume for
the rest of the day.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM.....Kurimski
LONG TERM......MG
AVIATION.......MPC



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.