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Area forecast discussion
National Weather Service La Crosse WI
543 PM CST Wed Nov 13 2019

Short term...(tonight through Thursday night)
issued at 151 PM CST Wed Nov 13 2019

GOES water vapor imagery showing mid-level vorticity center
responsible for snowfall overnight into today rotating eastward
across eastern WI. Surface observations showing deformation snow
falling across portions of north central Minnesota into east central Minnesota and
a secondary frontogenetically forced area from northeast Iowa into
southwest WI. Generally trace to 2 inch amounts reported so far
across the area through early this afternoon, highest across
portions of northeast Iowa. Otherwise, temperatures across the
forecast area were still on the cold side with readings at 1 PM
ranging from the teens across north central WI, and 20s elsewhere.

The mid-level wave exits east this evening with some breaks in cloud
cover expected after midnight as ridging builds in from the northern
plains. Overnight lows are expected to dip into the 10-20 degree
range with northwest winds generally less than 10 mph.

High pressure drops into the mid-Mississippi River valley Thursday
as a cold front drops to along the Minnesota/Canadian border. This will
produce southwest winds and some warm air advection across our area.
Look for highs pushing up the mid 20s to lower 30s, which is still
some 10 to 15 degrees below normal.

A weak mid-level trough and surface cold front drops through the
area Thursday night but should remain dry. Plan on overnight lows in
the mid-upper teens.

Long term...(friday through wednesday)
issued at 151 PM CST Wed Nov 13 2019

Mid-level ridge builds in with fervor Friday into Saturday, bringing
some moderation in temperatures to the area. Highs Friday and
Saturday are expected to top off well into the 30s, maybe a few
lower 40s? With this warm air advection/melting snow, expect an
increase in stratus unfortunately on Saturday.

Will have to watch for a chance of snow or rain/snow mix Saturday
night into Sunday as both the latest GFS/European model (ecmwf) show a fairly
vigorous mid-level trough moving eastward across the area.
Clouds/pockets of precipitation Sunday will hold temperatures down in
the 30s.

Another mid-level trough/closed low rotates through the area Monday
into Tuesday for another shot at some mixed rain/snow.

European model (ecmwf) and GFS are at odds for Wednesday. European model (ecmwf) shows another mid-
level wave/surface low moving through while the GFS builds mid-level
ridging into the central Continental U.S./Upper Mississippi River valley
region. With this uncertainty, will have to go with a model
consensus which yields a small-end chance of rain or rain/snow mix.
Either way, still looking milder with near highs normal in the
30s/lower 40s.


Aviation...(for the 00z tafs through 00z Thursday evening)
issued at 543 PM CST Wed Nov 13 2019

Light snow will taper off this evening but MVFR stratus will
linger over the taf sites through the overnight hours. Another
weak system moving through between 06z and 10z could produce some
flurries. Otherwise, high pressure builds in Thursday morning and
the stratus will scatter out with a return to VFR conditions from
mid morning into early Thursday afternoon.


Arx watches/warnings/advisories...


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