Area Forecast Discussion
Issued by NWS St. Louis, MO

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000
FXUS63 KLSX 031000
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
400 AM CST WED FEB 3 2016

.SHORT TERM:  (Through Late This Afternoon)
Issued at 311 AM CST Wed Feb 3 2016

Wrap-around type low level cloudiness will advect southeastward
through the entire forecast area this morning, southwest of
surface low moving northeastward through the Great Lakes region.
Although the radar echoes over western MO were weakening, there
may still be patchy drizzle or a few flurries this morning across
northeast and central MO and west central IL as embedded
shortwaves move through the upper level trough extending from MN
southwest into the Plains. Strong and gusty winds can be expected
today due to the tight surface pressure gradient between the
surface low over the Great Lakes region and the strong surface
ridge building eastward into the Plains. With low level cloudiness
and cold air advection temperatures will be nearly steady today,
much colder than yesterday.

GKS

.LONG TERM:  (Tonight through Tuesday)
Issued at 311 AM CST Wed Feb 3 2016

The low level clouds will shift east of our forecast area
tonight. This along with diminishing winds will lead to colder
lows tonight, although close to normal values for early February.
A warming trend will begin on Friday as the upper level trough
moves east of the region, and the surface ridge shifts southeast
of the area. A southern stream upper level trough may bring a
little patchy light snow to parts of the area late Friday night
and Saturday morning. More significant will be the deepening upper
level trough over the northern Plains on Sunday which will send a
cold front southeastward through our area Sunday night. Much
colder temperatures are expected Monday and Tuesday after a
relatively mild weekend with periods of light snow as the upper
level trough continues to deepen over or just east of our forecast
area. Although both the GFS and ECMWF models are similar with the
pattern, the GFS is deeper with the upper level trough/low over
the Great Lakes and Ohio Valley regions on Tuesday and forecasts
colder 850 mb temperatures down to -20 degrees C or less over
parts of our forecast area.

GKS

&&

.AVIATION:  (For the 06z TAFs through 06z Wednesday Night)
Issued at 1111 PM CST Tue Feb 2 2016

Focus will be on arrival of MVFR cigs. Expect cloud deck to spread
ewd across the area tonight. Winds will also increase thru the
night and gradually veer. Cigs will be slow to lift on Wed, but
shud reach low VFR by the afternoon hours. Expect clouds to sct
out during the late afternoon into evening hours. Winds shud
diminish late Wed afternoon into evening hours as well.

Can not rule out some light precip at UIN, possibly at COU. Some
uncertainty regarding what type of precip it will be. If clouds
are not deep enuf, any precip may be a light rain or drizzle. If
ice crystals are present, any precip shud be snow.

Tilly

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX


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