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Area forecast discussion
National Weather Service Lincoln Illinois
628 am CDT Fri Sep 22 2017

Short term...(today and tonight)
issued at 207 am CDT Fri Sep 22 2017

Main story for this first day of fall remains with the heat.
An upper level ridge remains firmly in place over the Midwest
this morning, and 850 mb temperatures are above the 90th
percentile for this time of year. Temperatures likely to again
reach into the 92-94 degree range in much of the forecast area,
with a few record highs possible. Cu-rule suggests some scattered
cumulus development over mainly the east half of the forecast
area. Several of the high-resolution models are hinting at some
isolated showers forming in this area by early afternoon. However,
given the strength of the ridge and little in the way of forcing,
will keep the forecast dry for now.

Long term...(saturday through thursday)
issued at 207 am CDT Fri Sep 22 2017

No real change in the forecast philosophy through this period.
Through early next week, the strong upper ridge over the eastern
U.S. Remains the driving force, with high temperatures remaining
in near record territory in the lower 90s. Temperatures start
easing off a bit on Tuesday with more cloud cover, but I would not
be surprised to see that day trending upward as well.

Upper pattern finally starts to break down around midweek, as a
strong shortwave ejects northeast out of The Rockies into the
upper Mississippi Valley. Main question remains with the speed of
the cold front passing through Illinois. The European model (ecmwf) fades out any
associated rainfall as it passes Tuesday evening, while the GFS
keeps showers going with a Wednesday passage. The Canadian model
is the odd one out, holding the ridge much longer until Thursday.
In any event, rain chances are not especially high, but the
highlight will be a significant cooldown.


Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 628 am CDT Fri Sep 22 2017

VFR conditions expected for the next 24 hours as high pressure
dominates the weather pattern across central Illinois. Afternoon cumulus
development expected with cloud cover becoming few-sct060. Winds
S-southeast 4-8 kts.


issued at 200 am CDT Fri Sep 22 2017

Record highs through the weekend:

Location Fri Sat sun
-------- ------- ------- -------
Bloomington 94/1930 92/1937 94/1933
Champaign 95/1891 94/1891 94/1891
Charleston 95/2005 93/2010 93/1933
Decatur 94/2005 92/2007 93/1933
Galesburg 92/1988 89/1937 90/2007
Olney 96/2010 94/1960 94/2010
Peoria 93/1930 92/1937 92/2007
Springfield 95/2005 93/2007 93/2007


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