Area Forecast Discussion
Issued by NWS Green Bay, WI

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FXUS63 KGRB 231941

Area Forecast Discussion
National Weather Service Green Bay WI
241 PM CDT TUE AUG 23 2016

Forecast discussion for routine afternoon forecast issuance

.SHORT TERM...Tonight and Wednesday
Issued at 241 PM CDT Tue Aug 23 2016

The latest RAP analysis and satellite/radar imagery show a shortwave
trough gradually lifting northeast over southeast South Dakota and
northeast Nebraska.  A relatively small cluster of showers and
storms is accompanying the shortwave, along with low clouds and
light showers spreading north over southern Iowa and northern
Missouri.  Starting to see high clouds ahead of the shortwave move
into central WI. Farther west, a cold front is moving east over the
central Dakotas, but is mostly inactive.  As the shortwave lifts
into the region late tonight, precip trends are the main forecast

Tonight...The shortwave trough over eastern South Dakota/Nebraska
will slowly lift northeast into Wisconsin late tonight.  Should only
see mid and high clouds arrive ahead of the system during the
evening, which should remain mild and breezy.  Then models point
towards low stratus developing ahead of the shortwave overnight when
increasing low level moisture arrives.  Additionally, models also
support showers and storms spreading from southwest to northeast
across the area late tonight.  Refined timing of precip chances a
little, but did not make many changes in regards to probabilities,
since concerns about coverage remain, given the low instability
progged for tonight. Models do show increasing shower/storm coverage
this evening over the northern Mississippi Valley, so this concern
may be unwarranted. With increasing clouds and higher dewpoints
expected, low temps will be warmer into the middle 60s.

Wednesday...The shortwave will continue to move across the region
during the morning, which will continue the chance of showers and
storms.  Concerns about coverage will carry over through the
morning, so capped precip chances in the likely range.  Between the
showers, could also see some drizzle or mist.  Drying will occur in
the mid-levels behind the shortwave as it exits during the
afternoon.  However, a cold front will be arriving during the the
afternoon, so will not be able to rule out additional showers
entirely, but only thinking isolated shower activity at best.  Low
clouds will be stubborn to improve ahead of the front.  With the
rain and clouds, muggy highs in the mid to upper 70s.

.LONG TERM...Wednesday Night Through Tuesday
Issued at 241 PM CDT Tue Aug 23 2016

Model solutions are a little better now in pushing
the showers and thunderstorms out of our area by Wednesday late
evening. The upper flow remains cyclonic Thursday even though a
surface high is starting to move in from the west. A scattered
shower is not out of the question but will keep the forecast dry.

Dry and seasonable weather expected for Thursday night through at
least part of Saturday. Medium range models keep rain west of the
forecast area through midday, with showers and thunderstorms
Saturday afternoon or evening ahead of a weak cold front. Should
be dry Sunday afternoon and Monday before another system arrives
in the fast zonal flow along the U.S. Canada border.

The models continue to have large run to run and model to model
differences regarding a possible hurricane for the southeastern
United States early next week.

.AVIATION...for 18Z TAF Issuance
Issued at 1211 PM CDT Tue Aug 23 2016

Low level moisture will push northward ahead of an upper disturbance
slowly moving northeast over the central Plains.  Though southwest
winds will be breezy, should have good flying weather through most
of the evening until this upper disturbance and low level moisture
move closer to the region.  This upper disturbance looks to arrive
overnight, bringing scattered showers and storms, along with quickly
deteriorating ceilings.  Both upstream observations and statistical
guidance point towards widespread IFR cigs arriving late tonight
through Wednesday morning, so was considerably more aggressive
dropping cigs in the tafs.  Showers and storms will be exiting to
the east by late morning, but ceilings will be much slower to

Beach Hazards Statement through Wednesday evening FOR WIZ022-040-


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