Area Forecast Discussion
Issued by NWS Green Bay, WI

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
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 40 41 42 43 44 45 46 47 48 49 50

FXUS63 KGRB 161141

Area Forecast Discussion
National Weather Service Green Bay WI
541 AM CST Sat Dec 16 2017

Updated aviation portion for 12Z TAF issuance

.SHORT TERM...Today...Tonight...and Sunday
Issued at 301 AM CST Sat Dec 16 2017

A weak clipper system will continue to produce light snow over
most of the area this morning. The snow should lift north and
diminish in the afternoon as the system departs. Additional snow
accumulation should be an inch or less. Highs will be close to

Surface high to our northeast will provide easterly flow across
lake Michigan tonight. This will keep low level moist and could
produce some every light snow or freezing drizzle near the lake
and bay. Clouds and winds off the water will keep lows about 10
degrees above normal.

Some very light snow or freezing drizzle is possible near the lake
and bay early Sunday, but it should be generally dry, with
temperatures about 5 degrees above normal.

.LONG TERM...Sunday Night Through Friday
Issued at 301 AM CST Sat Dec 16 2017

Upper air pattern will flatten for a time this weekend into the
middle of next week, before buckling occurs once again as western
ridge becomes re-established over about 130W. As the pattern re-
amplifies, models continue to suggest that a cyclone will impact
the state during the second half of the week. Until then, low
amplitude split flow will lead to small precip chances and temps a
bit above normal.

Forecast was a general blend of the 16/00Z ECMWF and GFS. Both
models on the 00Z run are reasonably close with storm system next
Thursday-Friday, given we`re still 120+ hours out. Indications
are that several inches of snow could fall across much of the
forecast area. Colder air still looks likely for the holiday
weekend as arctic air begins to move into northern U.S.

.AVIATION...for 12Z TAF Issuance
Issued at 541 AM CST Sat Dec 16 2017

Mostly MVFR ceilings today with VFR at times, especially
north of a Rhinelander to Marinette line. Scattered light snow or
flurries is possible through midday. Ceilings will lower into
MVFR range across the region tonight, with local IFR possible.
MVFR conditions expected Sunday with some very light snow or
freezing drizzle near the lake and bay.



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