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Area forecast discussion 
National Weather Service La Crosse WI
540 am CST Thursday Nov 26 2015

Short term...(today through Friday night)
issued at 239 am CST Thursday Nov 26 2015

Water vapor imagery coupled with rap 500mb analysis showing a long
wave trough digging into the western Continental U.S.. this was sending
moisture northeastward into the region in the form of clouds and
scattered pockets of light rain. Radar mosaic showing most of this
rain activity was confined across southern Wisconsin into central
Iowa/northern Illinois...within band of moisture transport/convergence ahead
of a surface cold front extending from western Upper Michigan
through western WI into central Iowa. Otherwise... fairly good
temperature difference across the area...ranging from middle/upper
30s across southeast Minnesota to the middle/upper 40s across
southwest/central WI.

For today into tonight...cold front moves very little today while a
weak area area of low pressure ripples northeast out of the Southern
Plains and across this baroclinic zone into southeast WI by late
this afternoon. Increasing isentropic lift/moisture transport ahead
of this wave combined with strengthening 850-500mb frontogenesis
will increase precipitation coverage through the day. Thermal
profile in place across the area will cause a wintry mix of
rain/sleet/snow for portions of northeast Iowa/southeast Minnesota into north
central WI by later this morning...transitioning to all snow by
later this afternoon. The rest of the area will see rain through the
day..transitioning to wintry mix/snow this evening. High pressure
building in from the northern plains pushes this precipitation east
of the area by sunrise. Before the precipitation moves out...could
see loss of cloud ice for some freezing drizzle/rain and light

Bottom of now...looks like 1 to locally 3 inches of snow
is possible mainly this afternoon into tonight northwest of a line
from Charles City Iowa to Winona Minnesota and Neillsville WI...with a
dusting expected across the rest of the area. Based on this and
glazing potential...will keep current Winter Weather Advisory in
place and have dayshift evaluate if expansion eastward is needed
based on precipitation type trends/intensity with 12z model run.

Dry/colder weather is then on tap for Friday into Friday night as
high pressure builds in across the upper Mississippi River valley
region. Look for highs Friday in the upper 20s to the middle 30s and
lows Friday night in the teens to lower 20s.

Long term...(saturday through wednesday)
issued at 239 am CST Thursday Nov 26 2015

Colder high pressure remains in control through the weekend with
highs in the 30s.

Snow/snow shower chances return to the area Monday through Tuesday
night with both the GFS/European model (ecmwf) showing a closed low moving out of the
plains and across the forecast area. Could see some
accumulations...but not going to nail down amounts at this point due
to uncertainty of focused forcing. Otherwise..slightly below normal
temperatures to continue with highs in 30s.


Aviation...(for the 12z tafs through 12z Friday morning)
issued at 540 am CST Thursday Nov 26 2015

LIFR/IFR ceilings expected today into this evening...with minor
improvement later tonight as the system starts to pull to the east.

Precipitation types are challenging as a simple degree change aloft and/or at
the surface will have significant impacts in what falls...and how visibilities
react. As it looks all starts as rain...a few hour mix of
sleet before transitioning to all snow. Loss of ice in the cloud
toward the end of the precipitation event would result in fzdz/rain for a
couple hours...if that occurs. Expect updates as observation and radar
trends lend some clarity to how soon/delayed some of the precipitation types
will be. Expecting snow accumulations at krst of 1 to 2...mostly on
grassy surfaces. An inch more wouldn/T surprise. Klse should stay
under an inch...dealing with liquid longer.


Arx watches/warnings/advisories...
WI...Winter Weather Advisory from noon today to midnight CST
tonight for wiz017-029-033-034.

Winter Weather Advisory from 9 am today to midnight CST
tonight for wiz032.

Minnesota...Winter Weather Advisory from noon today to midnight CST
tonight for mnz088-095.

Winter Weather Advisory from 9 am today to midnight CST
tonight for mnz079-086-087-094.

Iowa...Winter Weather Advisory from noon today to midnight CST
tonight for iaz009-018-019.

Winter Weather Advisory from 9 am today to midnight CST
tonight for iaz008.



Short term...das
long term...das

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