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Area forecast discussion 
National Weather Service Green Bay WI
419 am CDT Monday Mar 30 2015

Forecast discussion for routine morning forecast issuance

Short Tuesday
issued at 418 am CDT Monday Mar 30 2015

Northwest upper flow will prevail through the period with strong
jet streaks producing vertical motion later today through tonight.
The models are not in great agreement given the fact that whatever
precipitation we get will arrive this afternoon and evening.
Believe the differences are chiefly due to the initialization of
a strong jet streak that was coming ashore over British Columbia
at 00z. It looks to be better initialized by the European model (ecmwf) than the
other models and also looks better based on aircraft wind
observations at 06z. Not sure that this makes the further south
track of the European model (ecmwf) correct but hedged a bit that way and brought
higher probabilities of precipitation further south.

Precipitation type is also an issue as 925mb temperatures are initially
well above freezing though they cool during the late evening and
overnight due to evaporation and vertical motions. Think there could
be a half inch or inch of slush on grassy surfaces roughly north of
Highway 29. The jet streak exits the area by early Tuesday morning
with generally dry weather Tuesday.

Temperatures today and lows tonight should be about 5 degrees above
normal with slightly below normal temperatures Tuesday.

Long term...Tuesday night through Sunday
issued at 418 am CDT Monday Mar 30 2015

After the short term system departs there should be a period of
dry weather with a surface ridge passing across Wisconsin and the
arrival of a middle level ridge.

Strong warm advection ahead of a midweek system will bring enough
warm air into the area to keep any precipitation in liquid form.
The 00z European model (ecmwf) had most of the quantitative precipitation forecast on Wednesday remaining north of
Wisconsin while the 00z GFS...and 12z Gem-NH...had quantitative precipitation forecast across
almost the entire forecast area. Chance probability of precipitation across northern...and
part of central...Wisconsin Wednesday afternoon seemed a
reasonable compromise and fit well with surrounding forecast
grids. Looks like a pretty good bet that there will be showers
across the area Wednesday night and middle level lapse rates are
expected to be quite have also mentioned some thunder
Wednesday night. Kept a chance for showers lingering into Thursday
morning but not too confident in this since the GFS looks like it
ends the rain about 6 hours faster than the ec. Expect much above
normal high temperatures until after the system passes...then
highs are expected to be close to or below normal for the rest of
the period. Probability of precipitation remain slight chance at highest through the
upcoming weekend.

Aviation...for 06z taf issuance
issued at 1115 PM CDT sun Mar 29 2015

VFR conditions should continue into Monday afternoon. Attention
then turns to the next weather maker for Monday afternoon and
Monday night. Suprising low confidence with this system only being
less than a day away due to timing and path of the system. Not sure
where band of heavier precipitation will set up Monday night...but some
locations could see some more snow. For the 06z tafs...trended
toward the more southern solution and slower arrival of the
precipitation until Monday evening. Midnight shift can take
a look at the Canadian and European model (ecmwf) models to fine tune the forecast
with the 12z taf issuance.

Grb watches/warnings/advisories...


Short term.....Rdm

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