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Area forecast discussion 
National Weather Service Lincoln Illinois
310 PM CDT Wed Aug 27 2014

Short term...(this evening through thursday)
issued at 310 PM CDT Wednesday Aug 27 2014

Surface pattern is a little weak behind a now almost stationary
front over the central portions of the state. Warm weather and
humid conditions still in place and remnants of a decaying mesoscale convective system
working into the forecast area with the front providing focus for
the system. One thunderstorm in the Jacksonville producing a lot of
lightning and heavy rainfall. Models have varying solutions for the
progression of the boundary through the region and forecast
collaboration is resulting in a drier forecast than prev.
Concerened that the front is intitializing too far south...but will
back off the pops for now. Either way activity should recede
somewhat in the overnight hours as current convection is getting
more than a little support from diurnal heat. Once the sun sets,
the convective element reduces enough to allow the cooler air to
help progress the boundary to the south. The low then lifts just
west of the miss River Valley and brings the boundary back northward
as a warm front again, returning the chances for showers and
thunderstorms to the forecast area Thursday.


Long term...(thursday night through wednesday)
issued at 310 PM CDT Wednesday Aug 27 2014

The upper level ridge will be over the area again, but not as steep
as early this week. On the surface, southerly winds will bring the
return of moisture and warmer temperatures for Friday. The
associated surface front will be well northwest of the area, which
will slowly move east and southeast into the area for Friday night
through the weekend. As the front gets into the area, the chance of
thunderstorms will become likely, first in the northwest on Friday
night, then the whole area on Saturday, and then likely in the east
Saturday night. The chance of showers and thunderstorms will
continue through the rest of the weekend, but not as high as Fri
through Sat.

After the weekend system moves east, another system will be
approaching from the west and this will keep a chance of pcpn in
some portion of the County Warning Area through the rest of the weekend and into the
first part of next week. This system should move out of the area by
Tue night, so Wed currently looks to be dry forecast. However, with
the flow being very zonal and multiple boundaries will be in and
around the area through the period, the timing of pcpn chances will
likely vary from day to day.

Temps will warm a tad for Fri and Sat, but not as warm as what they
have been earlier this week. Then normal temps are expected for the
remainder of the forecast period. However, with pcpn on and off
through the period as well, humid/muggy conditions will likely


Aviation...(for the 18z tafs through 18z Thursday afternoon)
issued at 100 PM CDT Wednesday Aug 27 2014

Some low clouds building in along a stationary boundary in the
region. Broken/overcast cirrus blow off from the convective complex to the
west. Showers and thunderstorm development still anticipated along the
boundary as well through this afternoon and evening. Not
consistent representation of the llvl moisture in the models.
Concern that the overnight will see the low clouds hang around in
the MVFR category and may well be updating the overnight portions
of the tafs when new runs come in. Light flow throughout.


Ilx watches/warnings/advisories...


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

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