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FXUS63 KILX 220930

National Weather Service Lincoln IL
330 AM CST SUN NOV 22 2015

.SHORT TERM...(Today)

A very chilly start is on tap today due to the new snowfall.
Traditional cold spots from Altona to Lacon will see below zero
temps around sunrise. A 1028mb surface high pressure center will
pass just southwest of IL this morning. The ridge axis will progress
east of IL by 18z/Noon, allowing for surface winds to become
southerly this afternoon. Typically that means slightly warmer high
temps, but the new snow cover will keep temps a tick below potential
due to insolation going into melting the snow instead of sensible
heating. A band of altocumulus clouds is projected to move across
our northern counties today as well, with moisture mainly in the 850-
700mb layer per RAP and HRRR soundings. So a combination of snow pack
and cloud cover will limit highs north of I-74 to at or just below
freezing today. Southern areas with snow less than an inch should
see the sun help to melt off what feel on Saturday. High temps south
and southwest of Lincoln to Mattoon should reach the mid to upper
30s under sunny skies.


.LONG TERM...(Tonight through Saturday)

Surface high pressure ridge from eastern Texas into the Ohio river
valley at sunset will shift se into the Gulf Coast States Monday.
Meanwhile upper level trof over the OH/TN river valleys at sunset to
track east to the Atlantic Coast Monday morning, while another short
wave track northeast of central IL tonight into early Monday
morning. This feature may produce some mid level clouds over mainly
ne areas tonight and diminish by Monday morning. SSW winds 8-15 mph
to starts to modify temperatures. Lows tonight in the mid to upper
20s with some lower 20s over far northern CWA (Knox, Stark &
Marshall counties) where deeper snow pack of 6-10 inches is. Highs
Monday range from upper 30s to near 40F over northern CWA where snow
pack lingering while upper 40s SW CWA and into southeast IL.

Upper level ridge into IL Tue and into the eastern states Wed to
continue fair weather with temperatures continuing to modify. Lows
Monday night in the mid to upper 20s again with SW CWA near 30F. May
need to watch for patchy fog possibly developing over snow pack of
northern CWA later Monday night into early Tue morning as wind gets
lighter and have snow melt on Monday. Highs Tue range from lower 40s
from I-74 north to lower 50s sw CWA. Highs Wed around 50F northern
CWA and mid 50s sw CWA. Have slight chances of showers over the IL
river valley west of I-55 by Wed afternoon. Even milder highs Thu in
the upper 50s to around 60F.

Strong cutoff upper level low/trof digs over the Rockies during Wed
and Thu while surface low pressure to eject ne from the Texas
panhandle into the western great lakes Thu night and brings a cold
front east across IL in the Thu night to Fri time frame. 00Z models
still differ on timing of this front but generally show increasing
chances of showers from nw to se during Wed night and Thu with
likely pops Thu night into Friday. Rainfall amounts of 1-1.50 inches
during that time. Then cooler and drier weather follow late this


.AVIATION...(For the 06Z TAFS through 06Z Sunday night)

VFR conditions are expected this forecast period. High pressure
will drift across the region through Sunday morning bringing very
cold conditions to the forecast area. A band of mid level clouds
over north central Iowa was tracking southeast and should be
tracking across west central Illinois after 10z and further east
after 13z. Bases of the clouds should range from 6000-9000 feet
into the afternoon hours but precip is not expected with this
weak upper level wave that will push across the forecast area
during the day. Westerly winds at 8 to 15 kts tonight will back
into a south to southwest direction on Sunday at 7 to 12 kts


.ILX Watches/Warnings/Advisories...


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