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Area forecast discussion 
National Weather Service Lincoln Illinois
321 am CDT Sat Oct 25 2014

Short term...(today)
issued at 319 am CDT Sat Oct 25 2014

Main concern in the short term will be the dense fog again early
this morning, mainly in the northwestern parts of the County Warning Area. Unlike
last night, the dense fog has not developed yet in the County Warning Area and is
still located along and west of the Mississippi River. However, hrrr
model still forecast dense fog to move into the area. So will
continue the dense fog advisory as is, and will not extend in time or
area. Fog will be in areas east of the Illinois River, but not
dense. After the fog dissipates this morning, mostly clear skies
will be the rule for the area. Should be lots of sunshine to allow
temps to rise into the lower to middle 70s by this afternoon, which
is well above normal for the later part of October. Northwest winds
will only bring in a drier airmass for the day and beyond.


Long term...(tonight through friday)
issued at 319 am CDT Sat Oct 25 2014

1020 mb high pressure over over the northern High Plains, near the
eastern Montana and western Dakotas border, to settle into Illinois by
sunrise Sunday and weaken a bit to 1018 mb, then drift into
eastern Kentucky by sunset Sunday. This will continue fair weather
through Sunday night. 850 mb temps cool to 12-14c tonight into
Sunday morning before rising back up to 14-16c by sunset Sunday.
Lows mostly in the middle 40s tonight (fog limited overnight
tonight over central Illinois with drier air advecting in). Highs
Sunday mostly 70-75f, except upper 60s to near 70f from I-74

Strong low pressure of 1000 mb to eject NE from western Kansas Sunday
evening into Lake Michigan Monday night and bring a cold front east across
Illinois overnight Monday night and across the Wabash River valley in
eastern Illinois Tue morning. Breezy SSW winds Monday ahead of this storm
system to bring in warm air with highs approaching 80f. Have a
slight chance of showers and thunderstorms late Monday afternoon
far northwest County Warning Area by Galesburg. Best chances of showers and isolated
thunderstorms spread east across Illinois during Monday night (mainly
after midnight Monday night in eastern il) and Tue morning, then
diminish Tue afternoon from the west. Highs Tue range from lower 60s
from I-55 NW to upper 60s to around 70f from I-70 se. Temperatures
steady or slowly falling Tue afternoon behind the cold front. Slight
chance of showers early Tue evening near the Wabash River, otherwise
dry weather returns Tue night through Wed night as another high
pressure system settles over Illinois by Wed afternoon. Near normal highs
Wed/Thu in the upper 50s/lower 60s.

A weak northern stream short wave to dive se into upper level trof
over the eastern states and bring another cold front into Illinois by Thu
afternoon/evening. Have just slight chance of showers Thu due to
limited moisture. European model (ecmwf) model shows strong cutoff upper level low
near Illinois on Halloween along with showers, but other models like GFS
are drier. Models due agree that even colder air arrives on
Halloween with highs in the lower 50s central Illinois and mid 50s se of
I-70, while low temperatures near freezing next Friday night over
central Illinois and mid 30s in southeast Illinois.


Aviation...(for the 06z tafs through 06z Saturday night)
issued at 1150 PM CDT Friday Oct 24 2014

Mainly VFR conditions continue across central/southeast Illinois late
this evening as a shortwave trough and weak cold front moves
across the region, bringing cigs just above 3 kft above ground level. This
feature will move off to the east overnight, then clearing of the
cloud cover will allow fog to develop overnight. Given a similar
air mass to last night and winds expected to become light/variable
in the vicinity of the trough, vsbys between 1 and 3 miles
included for most central Illinois taf locations, with LIFR
category included for kpia. Gradual clearing with winds northwest 8-10
kts expected after 14z.


Ilx watches/warnings/advisories...
dense fog advisory until 9 am CDT this morning for ilz027>029-



Short term...auten
long term...07

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