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fxus63 kilx 080527 

Area forecast discussion
National Weather Service Lincoln Illinois
1127 PM CST Sat Dec 7 2019

issued at 318 PM CST Sat Dec 7 2019

Mild and dry conditions will be on tap across central Illinois for
Sunday with high temperatures topping out in the upper 40s and
lower 50s. Rain will develop Sunday night into Monday...followed
by sharply colder weather by Tuesday.


issued at 831 PM CST Sat Dec 7 2019

South winds and increasing cloud cover should help maintain a slow
temperature fall overnight. While thin cirrus is in place
currently, starting to see expanding stratus just south of St
Louis that should work into portions of central Illinois
overnight. Going forecast is in good shape this evening with no
major changes planned.


Short term...(this evening through sunday)
issued at 318 PM CST Sat Dec 7 2019

Mostly clear skies will prevail this evening before clouds
increase overnight. An area of low-level moisture currently in
place across far southern Illinois/western Kentucky will
gradually advect northward as southerly boundary layer flow
increases. Models do not have a good handle on the moisture, but
based on current satellite trends think clouds will develop/spread
northward across the eastern half of the kilx County Warning Area after midnight.
Hrrr hints at this, indicating overcast conditions along/east of
I-55 by dawn Sunday.

A short-wave trough over British Columbia and a deep upper low
spinning off the coast of northern California will phase over the
northern rockies...then will dig into the plains/Midwest early
next week. As this process unfolds, downstream ridging will push
temperatures into the upper 40s and lower 50s across central
Illinois on Sunday. While deep-layer moisture will initially be
lacking, several cams suggest scattered light showers will develop
along/west of the Illinois River by mid to late afternoon.

Long term...(sunday night through saturday)
issued at 318 PM CST Sat Dec 7 2019

Once the airmass moistens sufficiently, showers will become
widespread late Sunday night into Monday as stronger forcing
approaches from the west. Warm conditions will continue on Monday
as highs once again top 50 degrees: however, once a strong cold
front passes, temps will take a nosedive Monday night. 12z Dec 7
models continue to indicate that most of the precip will end
before the cold air arrives, so only a brief period of very light
snow is expected Monday night.

The coldest conditions will arrive Tuesday into Wednesday when
highs remain in the 20s and overnight lows plunge into the single
digits and teens. The lowest wind-chills from 0 to -5 will occur
late Tuesday night into Wednesday morning. After that, all signs
point to a rapid warm-up by the end of next week as the upper
trough lifts northeastward and a zonal flow pattern re-establishes
itself across the Continental U.S..


Aviation...(for the 06z tafs through 06z Sunday night)
issued at 1124 PM CST Sat Dec 7 2019

High pressure has moved to the upper Ohio River valley leaving
south winds across central Illinois. IFR/MVFR stratus is in place
across much of the lower to mid Mississippi Valley with some
patchy development near St Louis and SW Illinois. This stratus is
expected to expand northward across central Illinois overnight
resulting in low MVFR or possibly IFR conditions. There may be
improvement back to VFR during the day Sunday along with the onset
of gusty winds to around 20 kt or so, then MVFR may return again
after sunset Sunday evening.


Ilx watches/warnings/advisories...



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