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Area forecast discussion 
National Weather Service Green Bay WI
614 am CDT Sat Mar 28 2015

Updated aviation portion for 12z taf issuance

Short Sunday
issued at 355 am CDT Sat Mar 28 2015

Surface high will drift off to the east today while a weak upper
ridge edges in from the west. Weak warm advection should produce
temperatures 5 to 10 degrees warmer than Friday with mostly sunny
skies. Middle and high clouds will increase tonight and a steady
south winds will keep temperatures from falling much. Light snow
may arrive by daybreak in the far western part of the forecast
area. An upper trough and associated Pacific cold front will bring
several hours of precipitation in broad warm advection pattern
Sunday. Evaporative cooling should permit a few hours of wet snow
before freezing levels increase enough to change it to rain. Not
expecting much accumulation. Maybe an inch north of Highway 29
with less to the south. Whatever might fall will melt quickly in
the afternoon as gusty southwest winds bring in milder air from
the plains states.

Long term...Sunday night through Friday
issued at 355 am CDT Sat Mar 28 2015

Main concerns during this part of the forecast are timing...type
and location of precipitation.

A system that will impact the area in the short term should be have only included a chance for rain and snow in
north central Wisconsin 00z-06z Monday. Dry conditions should
prevail during the day on Monday as a surface ridge passes across
Wisconsin. The 00z versions of the European model (ecmwf) and Gem-New Hampshire had
quantitative precipitation forecast...associated with an upcoming system...farther to the
northeast than on previous runs. The 00z NAM was close to the 00z
GFS with location of quantitative precipitation forecast...which was farther northeast than the
ec and Gem...but was a bit slower than the other models. Recent
trends lead one to believe that the GFS has a better handle on the
situation...but there are still enough differences among the
models to keep confidence lower than one would like. Did not go higher
than chance probability of precipitation because of the differing model solutions. Have
nearly an inch of accumulation in northeast Wisconsin close to the
Upper Michigan border Monday night with little accumulation
farther to the southwest. A period of dry weather can be expected
Tuesday and Tuesday night.

A warming trend can be expected ahead of an approaching frontal
boundary and upper level short wave. This should result in much
above normal highs Wednesday and Thursday but will also bring
showers...mainly Wednesday and Wednesday night. Cooler
temperatures should prevail for late in the week. Other than
that...not enough consistency among models to discern much more

Aviation...for 12z taf issuance
issued at 613 am CDT Sat Mar 28 2015

VFR expected through late tonight with increasing clouds tonight.
Low level wind shear possible after 09z tonight with southwest
winds at 40 knots at 1000 feet above ground level and south winds around 10 knots
at the surface. Wet snow and IFR conditions will likely arrive
early Sunday. The snow will change to rain by midday. An inch of
snow or slush possible which should all melt as temperatures
climb above freezing in the afternoon.


Grb watches/warnings/advisories...


Short term.....Rdm

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