046 
FXUS63 KILX 291707
AFDILX

Area Forecast Discussion
National Weather Service Lincoln IL
1107 AM CST Fri Nov 29 2019

.SYNOPSIS...
Issued at 331 AM CST Fri Nov 29 2019

Cloudy and cool conditions will prevail across central Illinois
today...with high temperatures only reaching the upper 30s and
lower 40s. Widespread showers and a few thunderstorms will develop
tonight into Saturday as a strong storm system approaches from 
the west. 

&&

.SHORT TERM...(Today and tonight)
ISSUED AT 331 AM CST Fri Nov 29 2019

Despite dry easterly boundary layer flow, a weak short-wave 
trough moistened the profile sufficiently to bring a few very
light showers to central Illinois last evening into early this
morning. 09z/3am radar imagery shows the showers mostly confined
to locations east of I-55 and north of I-70 as the wave tracks
toward Indiana. Additional subtle short-wave energy embedded in
the southwesterly flow pattern will provide enough lift to trigger
sprinkles or patchy drizzle for the remainder of the morning and
perhaps into the early afternoon. Any significant rainfall will
likely remain just W/SW of the KILX CWA until late this afternoon.
Due to extensive cloud cover and continued easterly winds,
afternoon high temperatures will struggle to reach the upper 
30s/lower 40s.

As low pressure rapidly deepens over eastern Colorado and lifts
northeastward into Nebraska, a surge of WAA precip will arrive
across central Illinois tonight. Thanks to deep-layer
southwesterly flow aloft, copious amounts of moisture will be
transported into the region...with NAM precipitable water values 
exceeding 1.25, which is in the 99th percentile for this of year. 
Given strong forcing approaching from the west, think widespread 
showers will develop from southwest to northeast this evening.
In addition, MUCAPE values increase to 100-200J/kg across at least
the southern CWA...supporting thunder mention overnight. 

.LONG TERM...(Saturday through Thursday)
ISSUED AT 331 AM CST Fri Nov 29 2019

Showers and a few thunderstorms will continue on Saturday as a
warm front lifts northward through central Illinois. After early
morning lows in the upper 30s, increasing southerly flow by late
in the day will allow highs to range from the upper 40s
along/north of I-74...to the middle 50s along/southwest of a
Rushville to Effingham line. As the surface low tracks into Iowa,
an occluded front will pass from west to east Saturday evening.
Scattered convection will be possible along/ahead of the boundary,
with dry conditions returning in its wake.

The parent upper low will meander eastward across north-central
Illinois on Sunday, resulting in windy and cooler weather with
scattered rain showers. The rain showers may occasionally mix 
with snow across the far north during the day, then will mix with 
or change to snow further south across the remainder of the area 
Sunday evening. Little or no snow accumulation is expected as
temperatures remain above freezing until late Sunday night. Once 
the low departs, a return to cool/dry weather is anticipated for 
Monday through Thursday. 

&&

.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1101 AM CST Fri Nov 29 2019

A couple of showers and possibly a few thunderstorms will impact
the region through Saturday. Scattered showers lifting from
Missouri this afternoon will spread northeast across central
Illinois this evening. Coverage should initially be low, but more
widespread areas of rain will arrive overnight. There is some
instability that develops overnight and could result in a few
hours of scattered embedded thunderstorm activity. Meanwhile,
ceilings are already low MVFR and at times IFR across west 
central Illinois and these lower conditions will steadily spread 
east across the terminals through the afternoon with IFR becoming 
likely by late evening and continuing overnight. Southeast winds 
should prevail through the period, gradually increasing in 
strength and eventually becoming gusty during the day Saturday.

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...Barnes
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Deubelbeiss