Area Forecast Discussion
Issued by NWS Green Bay, WI

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000
FXUS63 KGRB 221031
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
531 AM CDT SUN MAY 22 2016

Updated aviation portion for 12Z TAF issuance

.SHORT TERM...Today...Tonight...and Monday
Issued at 307 AM CDT Sun May 22 2016

Strong high pressure ridge will drift over the western Great
Lakes region today into Monday. Warm temperatures and light winds
anticipated today followed with mild readings tonight with a
southerly flow developing.

Increasing pressure gradient on Monday with the approach of a
central and northern plains frontal system will produce gusty
south winds in the afternoon. Progs have overall been trending
slower with clouds and precipitation reaching northwest Wisconsin
Monday afternoon. Best upper jet support and instability remain
well west on monday and will also be running into the dry air mass
which has dominated the area for several days.

.LONG TERM...Monday Night Through Saturday
Issued at 307 AM CDT Sun May 22 2016

Mid level flow is forecast to become southwest across Wisconsin
by Monday evening as a 500mb ridge axis passes east of the state.
This will bring chances for showers and thunderstorms back to the
area for the upcoming work week and into the weekend.

Determining the onset of precipitation is the first challenge.
00z Models all appear to be on board with QPF across north
central Wisconsin Monday evening, but are split on how far east to
bring it after 06Z Tue. The GFS and NAM both had QPF over almost
the entire state 06Z-12Z, while the ECMWF and Canadian kept it
across about the northwest half of Wisconsin. SPC day 2 outlook
(12Z Monday through 12Z Tuesday) had general thunder across all
but southeast Wisconsin, and also had a marginal risk for severe
in the far western part of the forecast area. Have at least a
slight chance for showers and storms over all but the lakeshore
counties but kept chance POPs generally west of a line from IMT to
OSH. Think the marginal risk is reasonable since MU-CAPE in the
west reach 800-1000 J/kg there but strong upper support appears to
be lacking.

Agree with the day shift that any substantial risk of severe
weather won`t be until later in the forecast period. Will have to
wait and see how thing look on subsequent model runs.

High temperatures should remain above normal throughout the work
week, but they are expected to be closer to normal for the
weekend. Expect above normal lows due to clouds and, at times,
rain.
&&

.AVIATION...for 12Z TAF Issuance
Issued at 530 AM CDT Sun May 22 2016

Vfr conditions to continue through Monday. Few-sct
high based cumulus clouds expected this afternoon. South winds
will be on the increase Monday.
&&

.FIRE WEATHER...
Issued at 307 AM CDT Sun May 22 2016

Elevated fire weather conditions will continue into Monday
evening. Max temperatures today should climb into the upper 70s
and lower 80s away from the Bay of Green Bay and Lake Michigan.
Afternoon relative humidity readings will drop down in the upper
teens and 20s at most places with the lowest readings over sand
regions. afternoon relative humidity will be in the 30s along the
bay and lake. Did note some gusty northeast winds over some
Central Wisconsin observations sites Saturday afternoon. Glance
at past soundings indicated deeper mixing likely occurred. Winds
aloft expected to be lighter over central wisconsin today...so
the threat of gusty winds in that location should also be less
today. Best potential of gusty north winds over far eastern
Wisconsin this afternoon but this is also in a region of relative
humidity minimums in the 30 percents.

Conditions will be similar on Monday with respect to temperature
and humidity, however south winds will be on the increase by late
morning and afternoon with sustained winds of 10 to 15 mph and
gusts to 20 to 25 mph.
&&

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

$$

SHORT TERM.....TDH
LONG TERM......MG
AVIATION.......TDH
FIRE WEATHER...TDH



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