Area Forecast Discussion
Issued by NWS La Crosse, WI

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FXUS63 KARX 250910

Area Forecast Discussion
National Weather Service La Crosse WI
310 AM CST Sun Feb 25 2018

.SHORT TERM...(Today and tonight)
Issued at 310 AM CST Sun Feb 25 2018

25.09Z regional radars show the snow from last evening has moved
north and east of the forecast area. Surface winds have shifted to
the west, gusting between 25 to 30 kts. This is causing some blowing
and drifting snow, but overall impact appears minimal given the
heavy wet nature of the snow pack and visibility reductions mainly
in the 3 to 5 SM range. As a result, cancelled the remaining Winter
Weather Advisory at 3 AM CST. Difficult travel will continue into
Sunday morning for some areas until roads are treated and cleared.

For the rest of today into tonight, expect dry conditions and
clearing skies from south to north. Westerly winds will remain
quite breezy given a tight pressure gradient on the backside of
the departing surface low, but should begin to subside later this
evening and overnight. These winds could cause some additional
drifting of snow, especially along north-south oriented roads. As
a result, motorists should continue to watch for slick spots
through the day. Temperatures today will rise into the upper 20s
and 30s. Clear skies, lighter winds, and a fresh snow pack for
some areas will allow temperatures tonight to drop into teens to
low 20s.

.LONG TERM...(Monday through Saturday)
Issued at 310 AM CST Sun Feb 25 2018

Monday into Tuesday, the forecast area will be on the northwest
periphery of a broad surface high across the eastern CONUS. With
ridging aloft, temperatures will be warm with daily highs in the
upper 30s and 40s. Some locations may top 50 degrees Tuesday
afternoon, especially across the snow free areas of eastern IA into
southern WI. There is small chance for light rain across the eastern
and southern portions of the forecast area Tuesday afternoon into
Tuesday night as a weak cold front moves across the area, but any
accumulations look to be very light.

Focus then turns to a stronger storm system Wednesday night into
Thursday as a desert southwest short-wave ejects northeastward and
across the Upper Midwest. GFS/ECMWF ensemble means show the surface
low tracking from southwest MO into northern IL and eventually
the southern Great Lakes. That said, there is significant spread
between individual model members. QPF from GEFS plumes at La
Crosse range from zero to nearly two inches. Thermal profiles also
vary greatly with a hodgepodge of precipitation types. For what
it`s worth, 25.00Z GFS/ECMWF operational runs do hint at the
potential for warm air being wrapped into the system and this
would favor a wintry mix. For now, will hold to a model consensus,
which results in high POPs Wednesday night through Thursday and a
mix of rain, snow, or a rain/snow mix depending on surface
temperatures. Given such a large model spread, difficult to
provide anymore meaningful details at this time.

High pressure looks to build back into the region Friday into
Saturday, resulting in dry conditions and temperatures generally
in the 30s and lower 40s.


.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1030 PM CST Sat Feb 24 2018

Cigs/WX/vsby: ifr/mvfr cigs expected into the overnight hours as the
storm system exits east. The snow has ended for KRST, and looks to
exit east of KLSE by 06z. Trends favor clearing of the low deck
between 12-14z.

Winds: winds will be strong/gusty from the west/southwest through
the overnight and the better part of Sun. Expect some decrease Sun
evening as the pressure gradient relaxes.

The snow that has fallen is very wet in nature, and thus don`t think
blowing/drifting with be a significant concern at KRST.


Issued at 310 AM CST Sun Feb 25 2018

Little to no precipitation is expected through Wednesday. However,
strong warming Monday into the middle of the week could cause river
ice to break up, increasing the potential for ice jams. Persons near
rivers and streams should monitor ice conditions closely and report
rapid water level rises or flooding.




LONG TERM...Rogers
HYDROLOGY...Rogers is the U.S. government's official web portal to all federal, state and local government web resources and services.