Area Forecast Discussion
Issued by NWS Central Illinois

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FXUS63 KILX 301932

Area Forecast Discussion
National Weather Service Lincoln IL
232 PM CDT FRI SEP 30 2016

.SHORT TERM...(This evening through Saturday)
ISSUED AT 232 PM CDT Fri Sep 30 2016

No change in the location of the upper low since the last report,
still located near Louisville KY early this afternoon. Showers have
been increasing across areas east of I-55 this afternoon, with a few
thunderstorms tracking westward toward Danville and Champaign, as
well as just north of Lawrenceville. This low should finally start
drifting northward toward midnight, with most of the models
projecting it to reach the northeast Indiana area by late Saturday
afternoon. Until it exits the area, scattered showers will continue
into Saturday afternoon, most numerous over eastern parts of the
state. Overnight, this may trend toward more of a drizzle scenario
as cloud heights lower to a few hundred feet off the ground.
Temperatures will not be too far off of what we have been seeing,
with lows tonight mostly in the upper 50s and highs Saturday in the
upper 60s.


.LONG TERM...(Saturday night through Friday)
ISSUED AT 232 PM CDT Fri Sep 30 2016

A 5620 M cut-off 500 mb low remains nearly stationary over southern
Indiana and is expected to lift northeastward into northeast Indiana
by Saturday evening. Bands of showers wrapping around the system
into central/SE Illinois will taper off west to east Saturday
evening as it does so. Continued shower chances in areas roughly I-
55 eastward Saturday evening...then dry conditions forecast late in
the night.

High pressure will subsequently build into the region Sunday through
Tuesday producing fair and warmer weather. Highs will trend steadily
upward from the lower 70s Sunday to the upper 70s Tuesday...while
lows should be in the mid 50s through the period.

The next weather feature will be a large trough progressing eastward
via the western US. 12Z model runs are currently in relatively good
agreement through Tuesday...then details of the trough
evolution...associated surface low...and cold front diverge for
Wednesday and Thursday. Nevertheless...chances for showers and
thunderstorms develop Wednesday into Thursday as this feature
spreads in moist warm advection and an eventual cold front. Cooler
temperatures will ensue for late in the week following the cold
front. Highs should peak around 80 for Wednesday...then decrease
Thursday into Friday with highs ranging from the upper 60s to mid


.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1224 PM CDT Fri Sep 30 2016

Windows for VFR conditions are small and limited to only this
afternoon, as a fairly widespread area of ceilings 2000 feet or
less cover most of Illinois. While some modest increase in
ceilings is possible this afternoon, they should begin tanking
again this evening and widespread IFR/LIFR conditions are likely
by 06Z. Showers continue to be widely scattered and this trend
will continue tonight, making it tough to go more any more
specific than VCSH most of the time. Have added a VCTS mention for
KCMI this afternoon, as some lines of storms track west out of
central Indiana. By late in the period, MVFR conditions should
start to prevail, as the pesky upper low finally starts to lift
out of the region.


.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.