Area Forecast Discussion
Issued by NWS Central Illinois

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FXUS63 KILX 041142

Area Forecast Discussion
National Weather Service Lincoln IL
642 AM CDT WED MAY 4 2016

.SHORT TERM...(Today)
ISSUED AT 320 AM CDT Wed May 4 2016

A band of showers and a few thunderstorms is diving across central
and southeast Illinois early this morning. This convection lies just
ahead of a strong cold front, that is driven by a vigorous upper
wave diving into the Midwest. The rapid movement of this
front/precipitation will have the rainfall completely out of the
forecast area by mid-morning. It will be noticeable cooler across
the region today behind the front, with many areas only seeing high
temperatures in the 50s. Northerly post-frontal winds gusting to 30
mph at times will also make it feel cooler. Peak afternoon heating
and very chilly air aloft will combine to produce steep lapse rates
later today. This should allow a few showers or a thunderstorm to
pop this afternoon. However, coverage should not be significant and
have limited Slight Chance afternoon PoPs to roughly the eastern
half of the forecast area.

.LONG TERM...(Tonight through Tuesday)
ISSUED AT 320 AM CDT Wed May 4 2016

Upper ridging currently along the Rockies will be edging eastward
the next couple days, but pattern overall will be rather blocky,
with closed lows on either side of it. No real breakdown expected
until this weekend, when an upper wave will drop southeast from
Hudson Bay and finally boot the eastern low out of the way. However,
the western one will remain in the picture until Monday, with a
surface boundary extending eastward into the Midwest.

Longer range models are in decent agreement with pushing the front
through the area by Saturday evening, with scattered showers and
thunderstorms during the day and evening hours, before diminishing.
After that, the boundary becomes parallel to the upper flow between
what`s left of the ridge and shortwaves rotating through the Great
Lakes region. The GFS hangs onto this until late Monday night before
the front and associated rain chances lift back north. Meanwhile,
the ECMWF is much more aggressive in pushing it back beginning
Sunday evening as the lingering ridge axis slides overhead. Leaned
more toward the latter solution, although not quite as wet, and have
chance PoP`s over most of the forecast area Sunday night and Monday.
With the remnants of the western low only into the central Plains by
Tuesday, rain chances will be steadily increasing with time early
next week.

A warming trend will commence on Thursday, with highs mostly in the
mid 60s. As the thermal ridge builds east late in the week, a couple
days are expected with temperatures reaching near 80 degrees, before
the front pushes through. However, with the main troughing remaining
near the Great Lakes, temperatures behind the front should not be
especially cooler.


.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
Issued at 635 AM CDT Wed May 4 2016

Predominantly VFR conditions expected across the central Illinois
terminals today, although a few patches of stratus/fog will be in
the area for the next hour or two. Low end VFR CIGS will develop
around midday and possibly result in a few showers, especially
toward the Indiana border. Gusty northerly winds are expected to
develop shortly, and linger until this evening.


.ILX Watches/Warnings/Advisories...


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