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FXUS63 KILX 240952

Area Forecast Discussion
National Weather Service Lincoln IL
352 AM CST Sat Feb 24 2018

.SHORT TERM...(Today and tonight)
ISSUED AT 311 AM CST Sat Feb 24 2018
Deep trough over the southwestern portions of the country
continues the southwesterly flow into the Midwest aloft. Above
normal temperatures and continued rain chances through tonight in
the forecast. That being said, in the shorter term, precip 
moving in northwest of the IL River Valley this morning where the 
temps are still below zero...keeping the winter headline for
potential of light icing/bad early morning travel. Beyond that, 
areas in the south and eastern portions of the state the most 
susceptible to flooding due to where the rain has already fallen 
this week...and being under the highest qpf through tonight. 
Expanded the Flood Watch a line of counties north as the qpf 
forecast has shifted slightly to the north. 

For the showers this morning, the next wave is moving into the
region now, spreading that precip further north again. Pretty
decent continuity between models in a break in the activity from 
mid morning into early afternoon. Also in agreement that a front
will move in and with another round going into the evening hours,
scour the precip out of the region and set up for a break in the
rainy weather that has been in place this week. However, details
are missing as the position of the low is still a bit amorphous
with an elongated trough associated with this wave. Thunder likely
to accompany the afternoon/evening storms with better lift in a
stronger wave. Anything surface based will have a rather narrow
opportunity for development, looking for clearing within the lull
between waves. Severe threat will also be hinging on that
instability to a certain extent, even if the shear is pretty
decent. For now, much of the forecast area is in a Marginal Risk,
and the southeast in a Slight Risk, with the best chances to see
some warmer temperatures.  


.LONG TERM...(Sunday through Friday)
ISSUED AT 311 AM CST Sat Feb 24 2018
Front moving through the region tonight/tomorrow morning will move
the precip out, but not necessarily associated with a lot of cold
air. Through Sunday, h5 pattern remains southwesterly, with a
quick wave passing through the region dry which is a shift from
previous forecast runs. Forecast soundings quite dry through
Monday, with weak high pressure on the surface. Flow aloft sets up
in a more zonal pattern until midweek when the next wave develops
over the Rockies and brings an end to the brief dry period.
Tuesday night, precip returns to the forecast, even as the model
solutions diverge. The ECMWF splits a system that the GFS phases
and looks to deepen out of balance in comparison to the axis
orientation aloft. The blend of the two, as a result, is fairly
widespread pops midweek. Expect major changes to the forecast, but
the pops will likely remain in there mid week. Temperatures
throughout the forecast much milder than normal as the temp
profile really does not take much of a shift with the frontal
passage tonight.


.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1122 PM CST Fri Feb 23 2018

Overrunning ahead of wave pulling out of high plains trough
continues to produce heavy rainfall over southern Missouri and
will move northeast into the terminals over the next several 
hours. Was a little concerned with mix precipitation at PIA with
the onset, but despite brief clearing temps this evening have 
remained in the mid 30s so it appears that precip will be 
generally liquid. IFR to occasionally LIFR cigs can be expected 
through the day Saturday. There may be a lull between waves 
between late morning and middle afternoon in the rain, but Cigs 
will likely improve little given the forecasted inversion and 
northeast winds. Elevated thunderstorms will be possible as the 
main front pushes through during the late afternoon and evening. 
Winds will become quite gusty near and in the wake of the front 
and LLWS appears possible.


Flood Watch through this evening for ILZ056-057-061>063-066>068-

Winter Weather Advisory until 9 AM CST this morning for ILZ027-


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