Area Forecast Discussion
Issued by NWS Green Bay, WI

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000
FXUS63 KGRB 231644
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
1144 AM CDT MON MAY 23 2016

Updated aviation portion for 18Z TAF issuance

.SHORT TERM...Today...Tonight...and Tuesday
Issued at 325 AM CDT Mon May 23 2016

Most locations will start out sunny today with dry warm conditions.
Some mid to high level clouds may spill over the western two
thirds of the state today as a frontal system extending over the
northern and central plains approaches.

Progs have been consistent with holding off the precipitation
overall until tonight. Reaching Central and North Central
Wisconsin this evening and then Eastern Wisconsin well after
midnight. Precipitation primarily along and ahead of the 850
trough swinging through. The 850 boundary weakens overnight and
will also be encountering the initially dry air mass while
tracking eastward...so will keep pcpn chances on the lower side
over Eastern Wisconsin late tonight and then chance cat for
Tuesday. Upper heights rise later Tuesday to the west to diminish
or end the precipitation over at least North Central Wisconsin
earlier in the day. Some timing issues with respect to this 850
trough and surface front show up with the latest nam run the
slowest. Blend of the rest of model runs trend toward a
progressive end to the convection from northwest to southeast
during the afternoon.

As far as strength of storms tonight into Tuesday, the main
portion of the llj works into the northwest part of the state this
evening and it is possible a few near severe storms could work
into North Central Wisconsin this evening. SPC marginal risk of
severe storms appears reasonable this evening. The llj weakens
overnight and then is working with marginal instability overnight
into tuesday morning. The gfs does produce 1000 j/kg capes for
tuesday afternoon over eastern wisconsin. The NAM and SREF
produce values half of the gfs readings.

.LONG TERM...Tuesday Night Through Sunday
Issued at 325 AM CDT Mon May 23 2016

Upper level flow is expected to become southwest by the start of
the long term forecast, resulting in a rather warm and wet pattern
that is expected to last through the weekend. Timing of the
precipitation chances depends on timing of short waves in the
upper flow, and the location of a frontal boundary that will move
into Wisconsin tonight/Tuesday.

00z models suggested a lull in the precipitation for Tuesday
night with weak surface and upper level ridging across the area,
so kept both POPS and QPF relatively low for that period. There is
a better chance for showers and storms on Wednesday as an upper
level short wave moves into Wisconsin. Confidence in timing of
precipitation was on the low side, even for the early couple of
periods, and it decreases throughout the latter half of the week
and weekend. Have left the blended model solution along for the
rest of the forecast for that reason. Unfortunately this also
results in a chance for showers and storms through the end of the
forecast.

High temperatures should be at or above normal through the end of
the forecast. Overnight lows will be considerably warmer than
normal.
&&

.AVIATION...for 18Z TAF Issuance
Issued at 1138 AM CDT Mon May 23 2016

Very warm this afternoon with gusty southerly winds. Portions
of central into north-central and far northeast Wisconsin could
wind gusts of 30 to 35 kts. Much more stable air is expected near
the Great Lakes, where wind gusts around 20 knots are expected.
The chances of showers and thunderstorms will increase across
central into north-central Wisconsin later this evening and
continue overnight. The combination of the slow moving front and
dry air across eastern Wisconsin should allow for a much slower
arrival of the rain. The rain is not expected to reach the
lakeshore until after sunrise. Models indicated a band of showers
and storms moving across the area overnight into Tuesday morning.
There should be a break in the action, but secondary boundary
dropping south out of Upper Michigan could bring another
chance of showers and storms Tuesday afternoon into Tuesday
evening.

&&

.FIRE WEATHER...
Issued at 325 AM CDT Mon May 23 2016

One more dry day today with warm temperatures. Gusty south winds
combined with the warm temperatures and low afternoon relative
humidity will produce critical fire weather conditions through 8
pm. Headlines already in effect for today.

Increasing dewpoints with showers and storms tonight into Tuesday
will remove the critical conditions.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 8 PM CDT this evening FOR WIZ005-010>013-
018>021-073-074.
&&

$$

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



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