Area Forecast Discussion
Issued by NWS Green Bay, WI

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FXUS63 KGRB 192315

Area Forecast Discussion
National Weather Service Green Bay WI
615 PM CDT Mon Mar 19 2018

Updated aviation portion for 00Z TAF issuance

Issued at 203 PM CDT Mon Mar 19 2018

Quiet weather is expected for the rest of the work week.

The large scale flow across North America is expected to remain
at least somewhat split throughout the forecast period. For the
most part, the area is likely to remain positioned between the
main branches of the flow. This favors generally quiet weather
with little precipitation. Temperatures will undergo daily
fluctuations, but overall should be near or a little below

.SHORT TERM...Tonight and Tuesday
Issued at 203 PM CDT Mon Mar 19 2018

Blustery northeast winds and much colder temperatures were noted
across the region this afternoon. Temperatures were in the 30s,
except lower 40s at Waupaca and Wautoma.

The Hudson Bay high pressure system will dominate the weather
pattern through Tuesday afternoon. Clouds will be the main concern
tonight and Tuesday. First, the mid clouds across central and
north-central Wisconsin should erode over the remainder of the
region and early this evening, then move back eastward later
tonight into Tuesday. Along the Lake Michigan shoreline,
northeast fetch off the relatively warmer waters should allow for
low clouds to develop and move onshore. Medium confidence this
will happen due to the amount of dry air over Lake Michigan at the
moment. However, 850mb temperatures should get cold enough late
tonight for cloud formation to occur. With the clouds, there will
be a chance of flurries near the shoreline. Due more clouds
expected, took a blend of the warmer mav and cooler met guidance
for highs on Tuesday.

.LONG TERM...Tuesday Night Through Monday
Issued at 203 PM CDT Mon Mar 19 2018

The weather across the area will be dominated by a series of
anticyclones ridging south from the Hudson Bay area. Northeast
winds could still generate some flurries near Lake Michigan,
though the incoming air mass will be dry and work against that.

Some moderation in temperatures is likely during the middle to
latter part of the week as the northeast flow relaxes. The
northeast flow will strengthen again late in the week as another
anticyclone begins to ridge south from Canada while a cyclone
heads east across the Plains. The medium range models have begun
the expected trend of shunting precipitation with the cyclone
south of the area. That was nicely reflected in the forecast
initialization grids today, with just chance PoPs across the
southern part of the area late Friday night through Saturday

There are signs the overall pattern could become more favorable
for precipitation beyond the end of the forecast period. Ridging
is forecast to increase over the southeast CONUS, which would lead
to a southwest flow and make Gulf moisture available to systems
affecting the area. But that`s pretty far out in the forecast and
a distinct departure from the persistent pattern of the past few
weeks. So at this point it`s just something to watch in the coming

.AVIATION...for 00Z TAF Issuance
Issued at 615 PM CDT Mon Mar 19 2018

VFR conditions expected tonight with just some high
clouds. Lake effect clouds with bases of 3000 to 4000 feet may
form over Lake Michigan towards daybreak and move inland reaching
SUE and MTW. It is possible some of these clouds could get as far
west as GRB, ATW and OSH Tuesday morning. Just middle and high
clouds are expected elsewhere Tuesday and Tuesday night.



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