Area Forecast Discussion
Issued by NWS Central Illinois

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FXUS63 KILX 282002

Area Forecast Discussion
National Weather Service Lincoln IL
302 PM CDT WED SEP 28 2016

.SHORT TERM...(This evening through Thursday)
ISSUED AT 302 PM CDT Wed Sep 28 2016

Upper low continues to meander southeastward toward central Indiana
this afternoon. Next batch of scattered showers is starting to move
into areas around Bloomington and Champaign as the next trough
rotates into central Illinois. Most of these will fade with sunset,
but the northeast CWA will see some showers linger into evening, as
it is more downwind of Lake Michigan and its associated lake-effect
showers. Areas further west from the low toward the Illinois River
valley will see some clearing take place this evening, as clouds are
more diurnal in nature in that area.

Upper low will drift south into central Kentucky on Thursday, with
showers on the increase by mid morning across mainly the eastern
half of the CWA. Have kept the mention of isolated thunder over
areas along and east of I-57, where mid-level lapse rates will be a
bit steeper with the 500 mb cold pool in closer proximity. Once
again, clouds will be in no hurry to move out, although the Illinois
River valley may see enough sunshine to boost temperatures into the
lower 70s. Elsewhere, upper 60s should prevail.


.LONG TERM...(Thursday night through Wednesday)
ISSUED AT 302 PM CDT Wed Sep 28 2016

What you see is largely what you get over the next several days
across central and southeast Illinois. A pesky upper-level low will
continue to wobble over the Midwest through Sunday. It will be
accompanied by unseasonably cool temperatures, considerable cloud
cover, and scattered showers. The clouds and showers should exhibit
diurnal peaks. The model agreement is quite good in this scenario.
Any warming over the next few days should be quite gradual,
primarily through airmass modification.

The upper low will finally lift away from the area early next work
week, to be replaced by strong ridging and much warmer temperatures.
The next chance of appreciable rainfall will occur around the middle
of next week as strong cold front pushes into the area.


.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1212 PM CDT Wed Sep 28 2016

Extensive MVFR cloud deck associated with upper low over northwest
corner of Indiana has started to lift some, and central Illinois
TAF sites should be in VFR territory by 20-21Z. Clouds expected to
erode some with loss of daytime heating, but another deck of
ceilings at or below 2000 feet expected to push westward later
tonight, as the low will only drift across Indiana. Some
uncertainty as to how far west this will reach. Have only
mentioned TEMPO periods of MVFR ceilings at KPIA/KSPI, but sites
further east should see the lower ceilings moving in during the
09-11Z time frame, sticking around the remainder of the morning.
Gusty winds today will settle a bit late in the afternoon and
gradually turn more northerly overnight.


.ILX Watches/Warnings/Advisories...


SHORT TERM...Geelhart
AVIATION...Geelhart is the U.S. government's official web portal to all federal, state and local government web resources and services.