Area Forecast Discussion
Issued by NWS Central Illinois

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FXUS63 KILX 301057

Area Forecast Discussion
National Weather Service Lincoln IL
557 AM CDT Sun Apr 30 2017

.SHORT TERM...(Today and tonight)
ISSUED AT 323 AM CDT Sun Apr 30 2017

Upper low deepening over the Southern High Plains this morning
driving the weather through the short term as it amplifies the
flow across the country. Stationary boundary stretching across
Central IL out ahead of the main surface low on the OK/KS border
this morning keeping a bit of convergence in the wind field and
plenty of focus for the rich moisture feeding into the region.
Heavy rainfall across the Midwest prolonging the flooding concern
for the region and no changes anticipated in the Flash Flood Watch
for ILX.

Other than flooding, and northern drift of the boundary as a warm
front making the daytime highs surge ahead of where they were
yesterday...the main concern is how much of a chance the airmass
over Central and Southeastern IL is able to recover in the breaks
in the precip this morning/midday. HRRR and NAM both coming in
with enough of a break to see the CAPE push back over 1000-1500
J/kg with max heating later this evening ahead of the low moving
NW of ILX and into the Great Lakes. Considering the rapid
intensification of the low, SPC has left most of IL in a slight
risk through today and this evening.

.LONG TERM...(Monday through Saturday)
ISSUED AT 323 AM CDT Sun Apr 30 2017

Monday will still maintain low pops, mainly in the northern half
of the state for some residual showers in cyclonic
flow/instability showers through the afternoon. Temperatures
considerably cooler again with highs in the 50s for Monday.
Westerly flow out of the warmer temps in the SW and plenty of
sunshine provides some warmer temps for Tuesday...then drop again
for Wed as another quick wave brings clouds/precip midweek
briefly. Models having a rough time with the details on the back
end of the precip Wed night/Thursday.  Temperatures start an
extremely slow warm up back to the mid 60s by the end of the week.
Pattern shift from mid week to the end of the week still a bit of
inconsistency in handling the next weather maker.


.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
Issued at 553 AM CDT Sun Apr 30 2017

Forecast for much of today will remain in the LIFR/IFR
range...with a bump to MVFR only after sunset. Forecast will be
chasing some changing cigs and limited vis. Some models are
hinting at the breaking up of some of the
convection....potentially resulting in some scattered areas with
better conditions...but not expected to be predominant and for the
most part, left out. Could have made argument for more
predominant RA instead of SHRA...but some holes in the radar
returns will allow for some intermittent breaks in the precip
through the day...very similar to yesterday.


Flash Flood Watch through Monday morning for ILZ031-037-038-

Flash Flood Watch through Monday evening for ILZ051.



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