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Area forecast discussion 
National Weather Service La Crosse WI
950 PM CST Sat Dec 27 2014

Updated...
issued at 755 PM CST Sat Dec 27 2014

Clearing from west to east with drier air being brought in with the
clearing has resulted in some rapid drops in surface temperatures. Rst had a 10
degree drop from 4 to 7 PM. With fresh snow cover across most of the
northern 1/2 of the forecast area...and generally a lighter wind
regime for most...radiational cooling is good. Have lowered temperatures for
tonight as a result. Locations that decouple could fall an
additional 5 degrees.

Short term...(this evening through sunday)
issued at 230 PM CST Sat Dec 27 2014

Clouds will continue to decrease across much of the forecast area
late this afternoon into this evening as a weak ridge of high
pressure moves through. Plan on overnight lows ranging from around
11 across southeast Minnesota to 15-20 over southwest into central
Wisconsin. A cold front slides south across the forecast area Sunday
afternoon into Sunday evening and may generate some light snow or
flurries. There will be better chances for seeing some light
accumulations over northeast Iowa into far southwest Wisconsin.
It/S interesting to note that the NAM suggest light accumulations
are possible while the GFS and European model (ecmwf) are dry. Will keep a slight
chance of snow going in these areas and introduce flurries over
southeast Minnesota through central Wisconsin. Clouds will
increase along and behind the front as Arctic air advances into
the region. Highs on Sunday will range from the lower 20s over
north central Wisconsin to the middle 20s to around 30 across
northeast Iowa.

Long term...(sunday night through saturday)
issued at 230 PM CST Sat Dec 27 2014

Much colder air builds over the region in the wake of the front.
Monday night...we will see some of the coldest air we have felt
so far this season....at least since November...with lows falling
into the single digits to single digits below zero. Persistent
northwest winds will create wind chill concerns late Monday night
into Tuesday morning across the open areas of northeast
Iowa...southeast Minnesota...and north central Wisconsin where wind
chill values will fall into the -15 to -25 degree range. A Wind
Chill Advisory may be needed. Tuesday will be a cold day across the
region with highs mainly in the single digits above zero. Tuesday
night and Wednesday morning are looking rather cold as well with
temperatures falling into the single digits below zero. Again wind
chill values could plummet into the -15 to -25 degree range and a
Wind Chill Advisory may be needed. Temperatures recover a little on
Wednesday but it won't feel that much warmer thanks to southwest
winds of 12 to 20 miles per hour with gusts approaching 30 miles per hour in open areas.
Flow aloft looks to turn westerly by late next week into next
weekend with temperatures recovering to near normal values by
Friday...but this appears short-lived as another Arctic surge looks
to impact the region early next weekend.

&&

Aviation...(for the 06z tafs through 06z Sunday evening)
issued at 950 PM CST Sat Dec 27 2014

A cold front will drop southward across the region later on
Sunday...and along with a wind shift will come more MVFR ceilings Post
the boundary. Models favor a relatively narrow band of low
stratus...that likely drops south of the taf sites before 12z
Monday.

&&

Arx watches/warnings/advisories...
WI...none.
Minnesota...none.
Iowa...none.
&&

$$

Updated......rieck
short term...wetenkamp
long term....wetenkamp
aviation.....Rieck

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