Area Forecast Discussion
Issued by NWS Central Illinois

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FXUS63 KILX 300841

Area Forecast Discussion
National Weather Service Lincoln IL
341 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 06Z TAFS through 06Z Sunday night)
Issued at 1240 AM CDT Sun Apr 30 2017

Not much of a shift in the forecast, nor in the conditions.
IFR/LIFR is the rule across Central IL, and any improvements in
category are short-lived. With the frontal boundary invof DEC,
some variability in wind directions to be expected...and the shra
will continue... with some embedded thunder within the storm.
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 overnight. For
tomorrow...expect more of the same until later in the
afternoon/evening when a slow improvement is expected as the
surface low lifts to the NE.


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

Flash Flood Watch through Monday evening for ILZ051.



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