Area Forecast Discussion
Issued by NWS Central Illinois

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FXUS63 KILX 261943

Area Forecast Discussion
National Weather Service Lincoln IL
243 PM CDT TUE APR 26 2016

.SHORT TERM...(Tonight)
ISSUED AT 243 PM CDT Tue Apr 26 2016

A cold front near I-72 will accelerate southward across southeast IL
by early this evening. Large MCS over central/ne MO and western IL
(west of PIA and SPI) will spread widespread showers and scattered
thundestorms eastward across central and east central/southeast IL
rest of this afternoon and then diminish and past east into IN by
early evening. Strongest part of line is a bow echo moving toward St
Louis metro and areas south, and to track eastward aross southern
IL. Severe thunderstorm watch til 7 pm for Scott, Morgan, Sangamon,
Christian, Shelby, Effingham and Clay counties. Isolated to
scattered showers/thunderstorms recently develop ahead of MCS in
moderaterly unstable warm sector south of I-72 with Capes 2000-2600
J/kg. Bulk shear is 30-38 kts so a few of these thunderstorms could
become strong to even severe with damaging winds and large hail.
Brunt of CWA should be dry by mid evening, but this will be short
lived. 999 mb surface low pressure over central KS to deepen to 993
mb as it moves into southeast Nebraska by Wed morning and pulls
frontal boundary back northeast toward southwest IL. Showers and
scattered thunderstorms to spread ne into central and southeast IL
overnight especially late tonight into Wed. Lows tonight range from
around 50F from Peoria and Bloomington north to around 60F in
southeast IL from I-70 south.


.LONG TERM...(Wednesday through Tuesday)
ISSUED AT 243 PM CDT Tue Apr 26 2016

Energy rounding base of upper-level low centered over central
Rockies will be our next weather maker starting early Wednesday.
While this system will bring periods of showers/storms to the area
into Thursday, the severe threat should stay south of the area given
mainly sub 1000 j/kg CAPE values, and modest bulk shear values (30-
35 kts).

A lull in the rainfall threat is anticipated later Thursday into
Friday as Wednesday`s system departs, and as southwestern U.S.
troffing reloads. The next in our recent series of disturbances will
arrive for the weekend, along with a renewed threat of
showers/storms. While there are still differences in the details of
the weekend system, it is still looking wet overall. The slow moving
weekend system will depart by early next week, bringing another lull
in the rainfall.

Temperatures will trend downward heading into midweek, but still
hang near seasonal normals. So, it appears we have seen the last of
the 80 degree highs for at least a week or two.


.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1259 PM CDT Tue Apr 26 2016

Major adjustments to earlier forecasts with large MCS over
central/ne MO, southeast IA and west central IL tracking ESE
across central IL during this afternoon. This MCS is tracking further
northward and quicker than earlier forecasted by high res models.
Thunderstorms with MVFR conditions will be possible during mid and
late afternoon and exiting ESE of DEC and CMI by 00Z/7 pm. SPC
keeps the threat of severe storms sw of SPI this afternoon as a
strong to severe bowing line heading east toward St Louis metro
and to affect areas south of SPI and DEC during mid and late
afternoon. Low stratus deck of cloud from 500-1500 ft over
northern IL north of I-80 could be advected southward into central
IL overnight into Wed morning on increasing ne winds behind a cold
front that is currently near I-72. Cold front projected to track
into southeast IL late this afternoon and early evening. Currently
have fairly light and variably winds over central IL and these
winds to become NE and increase to 10-16 kts and gusts of 18-23
kts later tonight into Wed morning as winds veer east. Another
area of showers and thunderstorms to spread ne into central IL
later tonight and especially Wed morning with MVFR conditions
prevailing and possibly even IFR.


.ILX Watches/Warnings/Advisories...


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