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Area forecast discussion 
National Weather Service Green Bay WI
524 PM CST Monday Feb 8 2016

Updated aviation portion for 00z taf issuance

issued at 311 PM CST Monday Feb 8 2016

Colder with occasional light snow and flurries the next couple
days. Heavier snow showers in the Lake Superior snowbelt.

The large scale pattern will continue to be dominated by a ridge near
the West Coast and a trough over eastern noam. The pattern is currently
quite amplified. The amplitude of the pattern will fluctuate a bit
during the week...before a more substantial flattening occurs
during the upcoming weekend and early next week.

The northwesterly upper flow will direct cold air from Canada across the forecast area.
Temperatures will quickly settle to below normal levels...then remain there
for most of the rest of the forecast period. The coldest temperatures
are likely to occur early in the weekend...when a reinforcing
push of cold air from very high latitudes surges across the area. The
pattern favors considerable light snow and flurries...but with
limited moisture...amnts will be light. The exception will be the
Lake-Superior snowbelt...where headlines may be required at times.

Short term...tonight and Tuesday
issued at 311 PM CST Monday Feb 8 2016

Snow is the main concern during this part of the forecast. Surface
low pressure centered north of Lake Erie and an upper level
cyclone southeast of Lake Superior were slowly making their way
away from Wisconsin. Moisture and cyclonic flow on the back side
of the departing systems were bringing snow showers to the
forecast area today...especially across north central Wisconsin
where there were bands of lake effect snow showers at times. Winds
were increasing and temperatures falling on northwest winds in the
tight surface pressure gradient between the departing low and a
ridge over rockies/High Plains.

Aside from the lake effect in the north...snow showers were more
numerous over eastern than central Wisconsin. Quantitative precipitation forecast from 12z model
runs indicated that snow would slowly end from west to east...and
be finished in all but the far eastern counties. The exception is
in north central Wisconsin where winds remain favorable for lake
effect for quite some time and 12z GFS time/height plot had
measurable snow going at Iron wood all the way through 6 PM
Saturday. Based on the few totals we received in Vilas
County...snow accumulation during any one period should not be
very high. Also...did not see any reports of blowing snow
occurring in Upper Michigan or northern Wisconsin. Have left the
Winter Weather Advisory as it was for Vilas County. Will let the
evening shift decide whether it needs to be extended or not.

Expect colder temperatures overnight...with lows only in the
single digits and teens. It will not warm up much on Tuesday.
Highs should be mostly in the teens.

Long term...Tuesday night through Monday
issued at 311 PM CST Monday Feb 8 2016

Not much to latch onto to help with forecast details in the long
term part of the forecast. Lingering moisture and cyclonic flow
will keep lake-effect snow showers in the snowbelt through
Wednesday night. Flurries elsewhere will gradually end. Trended
more pessimistic with flow across Lake Superior is
likely to keep SC drifting across the forecast area at times. Raised
mins over north-c WI Tuesday night with the expectation of having more clouds.
Stuck with colder mins Wednesday there is a better chance of
getting more substantial breaks in the clouds by then. Trended
toward a blend of European model (ecmwf)-derived guidance products for maximum those have been verifying well lately.

A reinforcing surge of cold is likely to sweep into the area
Friday...and linger for at least the start of the weekend. The
medium range models were pretty modest with precipitation with the shortwave
preceding the cold anticyclone. Would not be surprised to see a
trend toward a bit more precipitation as we near the event.

No sig changes were needed to extended forecast initialization grids
generated from a broad-based blend of guidance products.

Aviation...for 00z taf issuance
issued at 524 PM CST Monday Feb 8 2016

Ceilings across the area varied between VFR and MVFR...with visibilities from
VFR to IFR in snow showers. Snow showers were most widespread in
eastern Wisconsin and in the Lake Superior snowbelt this evening.
Expect coverage to maintain itself early this evening....before
things winds down in all but the snowbelt. Gusty northwest winds
will calm down a bit after sunset...before increasing again on
Tuesday after sunrise. A steady MVFR ceiling is expected to settle
in across the taf sites later tonight and into Tuesday.

Grb watches/warnings/advisories...
Winter Weather Advisory until midnight CST tonight for wiz005.


short term.....Mg
long term......skowronski

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