Area Forecast Discussion
Issued by NWS Central Illinois

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FXUS63 KILX 281143

Area Forecast Discussion
National Weather Service Lincoln IL
543 AM CST Tue Feb 28 2017

.SHORT TERM...(Today and tonight)
ISSUED AT 331 AM CST Tue Feb 28 2017

First round of showers and thunderstorms moving out to the northeast
this morning, setting up for a brief break over Central Illinois
before development later today.  Major forecast issues surround the
next 24 hours, with temperatures climbing to above normal highs
again today, and likely a bit over guidance as well with strong warm
air advection setting up.  Southerly flow ushering in warm and humid
air to prime the environment for potential severe weather later
tonight. However, in the warm sector, could see some scattered
showers/thunderstorms during the day, but likely to remain somewhat
limited by a cap in place early. SPC has expanded the enhanced risk
area to Central IL mainly south of the IL river valley, particularly
for later this afternoon and tonight. As the front drops into the
region later tonight, convection will move down and through the
region as well... mainly after sunset and into the overnight hours.
Timing and placement of convective initiation is still troublesome
in the models. Potential for discrete supercells ahead of the front
and transition to a more linear environment is the general concern.
Mid level flow increasing through the afternoon providing ample
shear in addition to steep lapse rates and an increasingly unstable
environment as a moisture rich airmass advects northward from the
southwest. The threat will continue into the overnight hours as the
cold front begins to move through the region. Damaging winds and
large hail accompany the well as a tornadic threat,
particularly with supercell potential.

.LONG TERM...(Wednesday through Monday)
ISSUED AT 331 AM CST Tue Feb 28 2017

Cold front will be clearing areas south of I-70 early Wednesday
morning, with much of the precipitation pulling out of the area by
midday. Have maintained some 20-30% PoP`s into the afternoon across
the central and northeast CWA, as the upper wave crosses the area.
Temperatures will be steady or drop off over the CWA during the
morning, before making some modest afternoon recovery.

Longwave upper trough to cross the Midwest through Wednesday night,
as pattern shifts toward a series of fast moving waves dropping down
from the northwest. Clipper system remains progged to reach our area
by Thursday afternoon and will be out of the area by early evening.
Main impacts still look to mainly be along the I-74 corridor with
some light rain showers, which may change over to some flurries near
the Indiana border before ending. This pattern will quickly shift to
the east late in the week, as a broad upper ridge slides eastward
across the central U.S. This will result in a nice warmup for the
weekend, with highs returning to the 60s. Scattered snow showers
will be possible Friday night in the warm air advection ahead of the

Late weekend, the longer range models have quite a bit of
disagreement with the development of a storm system over the Plains
and Mississippi Valley. The GFS is much quicker in developing
showers Sunday afternoon and night, while the ECMWF largely keeps
things dry until the main cold front pushes eastward into the area
on Monday. This part of the forecast has lower confidence as a


.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 541 AM CST Tue Feb 28 2017
MVFR now and holding through mid day. Guidance would suggest
another solution, but with the enhanced low level moisture,
keeping the low deck in place. GUsty winds today in advance of
showers and thunderstorms for later in the day. A slow improvement
in the morning, but being conservative for now.


Issued at 331 AM CST Tue Feb 28 2017

Record highs for today:

Bloomington........ 70 in 1972
Champaign.......... 71 in 1972
Charleston......... 74 in 1972
Decatur............ 76 in 1972
Galesburg.......... 70 in 1972
Jacksonville....... 73 in 1981
Peoria............. 70 in 1972
Springfield........ 74 in 1972




LONG TERM...Geelhart
CLIMATE...Geelhart is the U.S. government's official web portal to all federal, state and local government web resources and services.