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Area forecast discussion
National Weather Service Green Bay WI
231 am CST Sat Nov 25 2017

Forecast discussion for routine morning forecast issuance

issued at 228 am CST Sat Nov 25 2017

Cooler today, but quiet weather with above normal temperatures
expected through the end of next week.

A broad band of progressive westerlies with low to moderate
amplitude will remain across southern Canada and the northern
and central Continental U.S. Through next week. The westerly upper flow will
keep the forecast area dominated by air masses of Pacific origin,
resulting in above normal temperatures. The primary storm track
will remain across Canada. That's unfavorable for generating an
inflow of Gulf moisture into the region, and will result in below
normal precipitation for the period.

Short Sunday
issued at 228 am CST Sat Nov 25 2017

Cooler air will overspread the area today. Temperatures will fall
until about 15z, then should remain nearly steady, and perhaps
gain a degree or two during the afternoon. Satellite suggests
clouds are dissipating faster than indicated by the guidance. But
the arrival of cooler air over Lake Superior will probably
eventually result in some lake-effect clouds. Those will affect
mainly the northeast 1/2 of the forecast area. Some sprinkles or
flurries are possible in that area as well.

Clearing skies and diminishing winds will allow temperatures to
drop off substantially tonight. But moderation will begin already
on Sunday. Trended temps toward the recent top performing
guidance products.

Long term...Sunday night through Friday
issued at 228 am CST Sat Nov 25 2017

The latest medium range models show relatively low amplitude flow
for this upcoming week, with split flow for the first half. Models
continue to have differences with the track of a southern stream
shortwave midweek, and have a slight preference for the ECMWF.

Sunday night through Monday night...a weak front will continue to
drop south across central and northeast WI on Sunday night. Little
to no moisture will accompany the front, so will stick with a dry
forecast. North of the front, high pressure will settle over the
area for a brief time, before shifting to the east on Monday. Winds
will return to the southwest as this occurs, with warm advection
precip remaining well north of the region over Lake Superior. Should
see another warm day and will raise temps. Then a stronger cold
front will move across the region on Monday night. Moisture remains
limited, but could see scattered to broken clouds accompany the

Rest of the forecast...more seasonable weather returns behind the
front for Tuesday and Wednesday as high pressure builds into the
region. Confidence remains low for Wednesday night into Thursday,
when a southern stream low pressure system, followed by northern
stream energy moving towards or over the area. This period will
probably be our next best chance of precip, though lack of moisture
will keep any precip light. Behind these systems, quiet weather
returns into early next weekend with seasonable temps.

Aviation...for 12z taf issuance
issued at 228 am CST Sat Nov 25 2017

Although cloud bases across much of the area have edged back into
the VFR category, they will probably drop back to MVFR over about
the northeast half of the area later this morning. Otherwise,
generally good flying conditions are expected through tomorrow.

Grb watches/warnings/advisories...


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