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FXUS63 KILX 231632

Area Forecast Discussion
National Weather Service Lincoln IL
1032 AM CST Tue Jan 23 2018

Issued at 1032 AM CST Tue Jan 23 2018

Clouds remain over the area and based on satellite loops, extend
back through MO and into KS. So looks as though cloud cover is not
going to be going away this evening. Models tend to be too
optimistic with this anyway. So will be adjusting cloud cover
through this evening and hang onto clouds longer than current
forecast tonight. Update to reflect this will be out shortly.


.SHORT TERM...(Today and tonight)
ISSUED AT 322 AM CST Tue Jan 23 2018

08z/2am surface analysis shows 997mb low over Michigan...with a 
cold front extending southward through Ohio into eastern Kentucky.
Even though the main synoptic front is well to the east, a 
surface trough is triggering an area of light precip across
central Illinois early this morning. As deep-layer cold air is
slowly drawn into the area, the rain has been changing to light
snow from SW to NE...with latest obs showing snow being reported
as far east as I-57. Radar trends suggest this main area of precip
will shift east into Indiana by 12z: however, plenty of low clouds
and flurries are noted upstream across Iowa. Think scattered
flurries will persist through the entire morning and perhaps into
the afternoon across the E/SE. Forecast soundings show the clouds
holding firm through the balance of the day, with partial clearing
taking place west of the Illinois River by early evening. High
temperatures will be in the middle to upper 30s, while brisk
northwesterly winds gusting 25-30mph will produce wind-chills in
the 20s. Clearing will gradually work its way eastward across the
remainder of the area by mid to late evening: however, a short-
wave trough currently over Montana will spread additional clouds
and a few flurries back into the area overnight. 

.LONG TERM...(Wednesday through Monday)
ISSUED AT 322 AM CST Tue Jan 23 2018

After a few lingering flurries across the eastern half of the CWA
Wednesday morning, skies will become mostly sunny across the board
by afternoon as the upper wave tracks into the Ohio River Valley.
It will be another cool day, with highs in the middle to upper 
30s. Once the wave departs, upper heights will rise markedly by
the end of the week...signaling a return to warmer conditions. 
High temperatures will reach the upper 40s and lower 50s on 
Thursday, then will climb well into the 50s by Saturday.

00z Jan 23 models continue to be in good agreement regarding the
timing of the next approaching system...with all solutions showing
a cold front passing through central Illinois on Saturday. The
airmass ahead of the front will be warm enough to support rain
Friday night into Saturday before colder air changes any lingering
showers to snow flurries Saturday night. After that, a period of
cool and dry weather will be on tap for Sunday and Monday before
conditions once again warm up by the middle of next week.


.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 553 AM CST Tue Jan 23 2018

IFR ceilings prevail at the central Illinois terminals early this
morning. Based on forecast soundings, it appears ceilings will
gradually rise to MVFR after 14/15z. After that, MVFR ceilings
will persist through the afternoon before slowly scattering from
west to east this evening. After a brief period of partial
clearing, an approaching wave will spread a mid-level overcast
back into the area overnight. W/NW winds will gust 20-25kt today
before subsiding to less than 10kt tonight.




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