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Area forecast discussion 
National Weather Service La Crosse WI
500 PM CST Wednesday Dec 24 2014

Short term...(this evening through thursday)
issued at 314 PM CST Wednesday Dec 24 2014

Isolated flurries and sprinkles will end early this evening as
low pressure exits the region and a surface ridge builds in from
western Minnesota/Iowa. Persistent stratus in place across the
upper Mississippi River valley should help keep low temperatures
above much of the forecast guidance values. Plan on lows tonight
ranging from the upper 20s to around 30s. The sref is suggesting
there could be some patchy fog tonight mainly north of Interstate
90 as winds become light. Will have to keep an eye on this
potential. Forecast confidence was not high enough to include it
in the forecast at this time.

The ridge slides east on Christmas day as low pressure develops
over the plains. A vigorous trough will dive into The Rockies
Thursday into Friday and eventually carves out a large trough over
much of the central and western Continental U.S.. across the local area quiet
weather is expected with winds switching around to the southwest.
Overall it will be a pleasant Christmas day with mostly cloudy
skies expected and high temperatures ranging from the lower 30s
over north central Wisconsin to the upper 30s across northeast

Long term...(thursday night through wednesday)
issued at 314 PM CST Wednesday Dec 24 2014

The surface low over the plains will lift towards the upper
Mississippi River valley Friday night into Saturday and will
interact with a middle level trough pushing east out of the northern
plains. This system looks to spread light rain or snow across the
region late Friday morning into Friday afternoon with most of the
precipitation switching over to snow Friday night into Saturday
morning. NAM forecast soundings suggest that there may not be ice
aloft Friday night and locations that are below freezing could
see freezing drizzle. The precipitation type will likely start out
as drizzle Friday afternoon into Friday evening then we should see
a switch over to snow as the middle level trough moves in. Will have
to keep a close eye on the freezing drizzle potential especially
over southeast Minnesota through north central Wisconsin where
surface temperatures could be cold enough to support it.

Winter then makes a return Saturday into Sunday with highs cooling
into the 20s and lows falling into the teens and possibly the single
digits. Much colder air then settles into the region. Another trough
then dives into the western Continental U.S. Sunday night into Monday and will
bring much colder temperatures to the area. Some light snow is
possible into Tuesday as the trough pushes in but then rather chilly
temperatures move in Tuesday into Wednesday. Low temperatures
Tuesday night look to fall into the single digits below zero across
much of the forecast area. On new years appears highs will
struggle to get out of the single digits above zero with
temperatures falling single digits below zero for the evening and
overnight hours. Plan on having to bundle up for the new years evening


Aviation...(for the 00z tafs through 00z Thursday evening)
issued at 500 PM CST Wednesday Dec 24 2014

Extensive IFR/MVFR stratus still in place across the region early
this evening...per latest fog/stratus satellite imagery and surface observation.
Models hinting that the clouds could break into a scattered deck on
xmas...moreso the GFS than the NAM. Even the pessimistic NAM though
would bring its quasi-clearing line up to I-90 toward 00z xmas
night. Will keep the low cloud trend for now...but the next set of
tafs may need to introduce a period of scattered conditions. Clouds would
quickly return later Thursday night as an upper level shortwave trough
works into the plain states.


Arx watches/warnings/advisories...


Short term...wetenkamp
long term...wetenkamp

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