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Area forecast discussion 
National Weather Service Lincoln Illinois
336 am CDT Wednesday may 27 2015

Short term...(today)
issued at 336 am CDT Wednesday may 27 2015

A weak front will slide southeast through the County Warning Area today. Showers and
thunderstorms can be expected along this front during the day and
radar loop shows that some have already developed and are moving
east-northeast. Over most of the area they will be scattered...but
over the southern part of the state they should be more widespread.
Will have higher probability of precipitation in out southeast with probability of precipitation lowering as you go
northwest. Believe north half of the County Warning Area will be dry by this
afternoon. Winds will be southwest ahead of the front but then
gradually switch to more west-northwest by late afternoon...after
the front moves through. With partly sunny skies...should be plenty
of sunshine to allow temperatures to reach to between 80 and 85.


Long term...(tonight through tuesday)
issued at 336 am CDT Wednesday may 27 2015

Brief break in the precipitation for much of central Illinois tonight and least until later in the day. Some low probability of precipitation still in
the south tonight as the front settles into the region, otherwise
some weak ridging building in the wake of the exiting wave.
However, just as quickly, southwesterly flow reestablishes itself
over the country. The low digging in over the western half of the
Continental U.S. However is a bit weaker in the last few runs and The Heights
not quite responding accordingly in the models. Although the upper
pattern may not pan out to be exactly as depicted, Midwest still in
line for another unsettled end of the week with shower chances
coming back in tomorrow night and remaining in place through the
first half of the weekend. Front moving into the region Friday
night/Sat associated with a distinct upper low moving across southern
Canada and the Great Lakes... will usher in cooler and drier air for
the end of the weekend and first portion of next week with temperatures
briefly dropping into the 60s and 70s through Monday.


Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 1105 PM CDT Tuesday may 26 2015

Coverage of showers across the forecast area and affect on ceilings
for the remainder of the night...with the potential for some
MVFR visibilities in fog by Wednesday morning. Little change from previous
forecast discussion with a weak cold front settling southeast
into the area by dawn Wednesday coupled with a rather weak upper
level wave which will produce widely scattered-scattered showers
and isolated thunderstorms and rain. Based on the latest local objective analysis
it appears the focus for any scattered convection will shift
into central and then southern portions of the forecast area.
Coverage still appears too limited at this time to include
much more than a thunderstorms in the vicinity.

There may be a brief period of MVFR fog in pia...bmi and cmi but
it appears the scattered to broken clouds (vfr) and south to
southwest winds around 10 kts will prevent any widespread
formation. Models also show a narrow band of MVFR ceilings pushing
along the weak front in the 10z-15z time frame from northwest to
southeast but each model run has had varying solutions with
respect to coverage over our area. For now will introduce a
scattered cloud deck at around 1500 feet at pia and bmi tomorrow
morning. Surface winds will remain from a south to southwest
direction overnight with speeds of 8 to 13kts and then veer more
into a westerly direction on Wednesday at 10 to 15 kts.


Ilx watches/warnings/advisories...


Short term...auten
long term...hjs

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