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Area forecast discussion 
National Weather Service Lincoln Illinois
256 PM CDT Tuesday Aug 30 2016

Short term...(this evening through wednesday)
issued at 256 PM CDT Tue Aug 30 2016

Weak cold front is slowly approaching central Illinois, with
slightly cooler and drier air behind it. However, the boundary will
continue its slow approach, not expecting the drier air until
tomorrow evening. Instead, the warm and muggy airmass that is in
place today will remain through the overnight, bringing the chances
for periodic showers and patchy fog. Models are having a hard time
dealing with the current convection, and is overly done. Reduction
in the overnight pops as a result overall...keeping the mention more
scattered than not. Much of the lift provided for any overnight
showers will be in the form of mesoscale outflows or small waves
within the swrly plume of moisture streaming into the plains and the
Midwest along and ahead of the boundary.


Long term...(wednesday night through tuesday)
issued at 256 PM CDT Tue Aug 30 2016

Models agree on a substantial cold front pushing southward
through the area Wednesday, reaching at least I-70 by Thursday
evening. Keeping a slight chance of thunderstorms to the south of I-
70 as a result of frontal timing, but conditions should be all dry
across the forecast area by 9 p.M. With dewpoints falling into the
50s overnight, down from the humid 70s prior to the frontal passage.

Thursday through the weekend...dry conditions can be expected as the
cool and dry air mass slowly moderates through the period and strong
high pressure to around 1026 mb develops over the Great Lakes
region. Expect highs in the upper 70s Thursday and Friday gradually
rising to the mid 80s by Monday and Tuesday. Dewpoints should be in
the 50s to lower 60s through Saturday, increasing to around 70 by

As troughing slowly works its way eastward into the central U.S.
And a cold frontal zone with several disturbances tracking along it
develops in the plains...chances for precipitation look to start
again northwest of the Illinois River on Labor Day Monday...spreading
throughout central Illinois by Tuesday.

A tropical depression with 35 mph winds 300 miles west of Key West
Florida is projected to slowly turn northeastward toward Florida over the
next day...strengthening to a tropical storm. This tropical system
should keep its rainfall well southeast of Illinois. But if traveling to
Florida or the southeast Atlantic coastal region, monitor later
forecasts and statements from the National Hurricane Center (nhc)


Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 1243 PM CDT Tue Aug 30 2016
forecast a little tricky this afternoon with ongoing precip with
sct ts at the moment, and models poorly depicting this
afternoon/evening activity as another round moves into central Illinois.
Chances better for pia and bmi...a little earlier for spi and Dec,
and cmi a bit of a wild card. Hrrr concentrates qpf/shower
activity across the north, on or just north of pia, and ending
most of the precip btwn 00-03z. Taf follows that trend with low
cigs with the cbs, like this morning. Vis drop after midnight with
llvl moisture enhanced by the precip and light and variable winds.
MVFR for cmi spi and Dec...IFR for pia and bmi.


Ilx watches/warnings/advisories...


Short term...hjs
long term...Onton

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