Area Forecast Discussion
Issued by NWS Central Illinois

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FXUS63 KILX 160947

Area Forecast Discussion
National Weather Service Lincoln IL
347 AM CST Fri Feb 16 2018

.SHORT TERM...(Today and tonight)
ISSUED AT 347 AM CST Fri Feb 16 2018

09z/3am surface map shows a cold front along the Ohio River...with
rain showers lingering behind the boundary as far north as the
I-70 corridor. Based on forward speed of front, have held on to
PoPs across the SE KILX CWA through 15z/9am. Meanwhile further
north, light radar echoes are spreading across west-central and
northwest Illinois in association with an approaching short-wave
trough. Have seen a few obs of light snow upstream across Iowa,
but none thus far in Illinois. Have included scattered flurries
for the next few hours along/north of a Beardstown to Hoopeston
line accordingly. Skies will initially be overcast this morning,
but will become mostly sunny by mid to late afternoon everywhere
along/west of I-57. Highs will range from around 30 degrees far the lower 40s south of I-70. Skies will clear
across the board this evening, followed by increasing cloudiness
overnight as the next short-wave approaches from the west. Lows
will range from the teens northwest to the upper 20s far


.LONG TERM...(Saturday through Thursday)
ISSUED AT 347 AM CST Fri Feb 16 2018

Upper wave will traverse the region on Saturday, but will have
limited deep-layer moisture to work with. Have therefore kept PoPs
in the chance category and have focused them mainly from late
morning through the afternoon. The atmosphere may be cold enough
to support a brief rain/snow mix as the precip begins, but that
will quickly transition to all light rain as high temperatures top
out in the 40s.

Mild and dry weather will be on tap for Sunday before an active
weather pattern takes hold next week. Southwesterly flow will
establish itself across the central/eastern CONUS...setting up a
period of warm and unsettled weather Monday through Wednesday.
00z Feb 16 models remain in very good agreement initially...with
surface low pressure tracking from the Plains into the southern
Great Lakes on Monday. This places central Illinois in the warm
sector of the system, allowing temperatures to soar well into the
60s and perhaps even reaching 70 degrees across the S/SW CWA.
Thanks to ample deep-layer moisture and strong upper forcing,
widespread showers will occur. Instability becomes strong enough
to support thunder as well...particularly from Monday afternoon
through Tuesday. Model solutions diverge somewhat after that,
with the GFS showing a trailing cold front edging eastward and
precip coming to an end from west to east Tuesday night into
Wednesday. Meanwhile, the ECMWF is slower with the eastward
progression of the front and features much more post-frontal
precip lingering across the area through Wednesday. At this point,
will hit PoPs hardest Monday through Tuesday night, then will
begin lowering precip chances on Wednesday. Total rainfall next
week could be significant...with early indications suggesting in
excess of 1 inch across all of central Illinois...and perhaps over
3 inches south of the I-70 corridor. The heaviest rainfall axis
and exact totals will likely be adjusted with time, so stay tuned
for the latest forecast for details on this potential heavy rain


.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 1119 PM CST Thu Feb 15 2018

DEC and CMI will start with MVFR conditions due to the light rain
that is moving across both sites. However this will not last long
and have conditions improving quickly by 7z at both sites. Cigs
will also be coming up into the mid range, so VFR condtions for
these two sites expected most of the night. PIA/BMI/SPI will also
see VFR conditions most of the night. Models forecast a lower MVFR
deck between 1.5kft and 3kft to move over the sites late tonight
and early tomorrow morning. This has been indicated for several
runs so will keep in TAFs for all sites. These MVFR cigs will last
til around the noon hour at all sites and then become scattered
for the afternoon hours. Then expecting scattered to clear
conditions tomorrow later afternoon through evening. Winds will be
northwest through the period with some gustiness at time of MVFR
clouds moving across the area.




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