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Area forecast discussion 
National Weather Service La Crosse WI
1150 PM CDT Thursday Mar 26 2015

Short term...(this evening through friday)
issued at 322 PM CDT Thursday Mar 26 2015

At 3 PM...a Canadian cold front extended from Green Bay to the
Twin Cities to Aberdeen South Dakota. This front was producing a
scattered to broken deck of 2500 to 4500 foot cloud deck across
the upper Mississippi River valley. Soundings show that subsidence
will be found north of Interstate 94 by 9 PM...north of Interstate
90 by 12 am...and across the remainder of the area by 3 am.
Concerned that the clouds may be decreasing too fast in the will have to watch this trend closely this evening.
Also it is interesting that the NSSL WRF synthetic visible
satellite product indicates that several bands are coming off of
Western Lake Superior and these bands continue to move south
across southeast Minnesota and northeast Iowa during the evening
and overnight. This is just something else to watch tonight. With
skies forecast to become mostly clear and north winds between 5 to
10 miles per hour...expect temperatures to cool rapidly overnight. The
coldest temperatures /in the single digits/ will be found in The
Bog areas of central Wisconsin. Meanwhile the remainder of the
area will see low temperatures in the teens.

On Friday...skies will be mostly to partly sunny...but the air
mass will be very cold with 925 mb temperatures between -4c and
-8c. This will cold air along with some snow on the ground in some
places will keep high temperatures in the lower and middle 30s.

Long term...(friday night through thursday)
issued at 322 PM CDT Thursday Mar 26 2015

On Friday night...the 26.12z models continue to show that a short
wave trough will move quickly southeast through western Minnesota
and western Iowa. Soundings continue to show that there will be
some moisture found between 550 and 450 mb. This is Colorado-located
with some weak there is a possibility that some of the
middle and high clouds from this system may creep into the areas west
of the Mississippi River river during the evening and early
overnight. With mostly clear skies expected much of the
overnight and light will be another cold night across
the area. Light tonight...the coldest temperatures /in the single
digits/ will be found in The Bog areas of central Wisconsin.
Meanwhile the remainder of the area will have low temperatures in
the teens.

From late Saturday night into Sunday...the models continue to
struggle with the timing of a short wave trough through the
region. The GFS...Gem...and NAM bring precipitation into the area
between 06z and 12z. Meanwhile the European model (ecmwf) keeps the area dry until
Sunday. With these time differences kept the precipitation chances
in the 20 to 50 percent range for Saturday overnight and Sunday
afternoon...and raised the precipitation chances to likely on
Sunday morning where the best consensus was found. Like previous
runs...the models suggest that there may be a brief wintry mix
north of Interstate 90 at precipitation onset and then change over
to rain. With the clouds and precipitation lingering throughout
the day...the European model (ecmwf) and Gem are about 10 degrees colder than the
model consensus. Due to this lowered the high temperatures by a
couple of degrees.

Beyond this time period...the models continue to show a general warm
up...but there could be some issues from time to time as northern
stream short waves bring bouts of cooler temperatures at times.
Another issue is that there are differing opinions on the track
and timing of these systems and this greatly influences the
precipitation timing.


Aviation...(for the 06z tafs through 06z Friday night)
issued at 1150 PM CDT Thursday Mar 26 2015

Expect clear skies overnight at krst/klse as VFR cloud deck slides
to the south. Some thermal cumulus are possible late Friday
morning and continuing through the afternoon in the 3000 to 3500
feet above ground level layer...but given dry subsident airmass...will not introduce
any ceilings at this time. Northerly winds tonight will become
light and variable Friday as surface high pressure drifts across
the region.


Arx watches/warnings/advisories...


Short term...boyne
long term...boyne

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