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Area forecast discussion 
National Weather Service Lincoln Illinois
308 am CDT Wednesday Jul 27 2016

Short term...(today and tonight)
issued at 307 am CDT Wed Jul 27 2016

The stationary front will remain just southeast of IL, roughly along
the Ohio River valley. A relatively weak pressure gradient north of
the front under a weak surface high will set the stage for patchy
fog to develop, especially in low lying areas. Locally dense fog has
already begun to form from Salem to Robinson, and those conditions
will linger through an hour or so after sunrise. Once the fog
clears, skies will be partly cloudy with diurnal cumulus forming in
much of the area. A plume of moisture streaming north of the
stationary front will keep rain and storm chances going for our
counties along and south of I-70 today. Storm chances will expand in
coverage to include the remainder of our counties later tonight,
with slight chance pops north of I-70 and chance pops along and S of I-
70. The potential for severe wind and/or hail remains low.


Long term...(thursday through tuesday)
issued at 307 am CDT Wed Jul 27 2016

On Thursday, another wave ripples through the nwrly flow and dives
into the Midwest, interacting with what remains of the boundary,
spreading showers and thunderstorms through Friday. Once the system
moves to the east a bit, showers will become more widely spread, but
likely linger through Saturday. High pressure ridge builds into the
Midwest and have continued to trend back on the pops from the
blended forecasts as well, but Monday starting to show some
consistency with small disturbance moving into the region with
another round of precip, particularly to the south. Will need to
watch that trend.

Temps trending slightly cooler through the first half of the weekend
with the more northwesterly flow and the precip influence. 850mb
temps not moderating quite as much, and holes/breaks in the cloud
cover for the next couple days could result in some isolated warmer
temps. After the first half of the weekend, the building heat in the
western half of the Continental U.S. Begins to shift, putting another warming
trend in place for central Illinois into the first of next week.


Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 1232 PM CDT Tue Jul 26 2016

Main concern this taf period is for potential of MVFR conditions
in fog later tonight. Guidance numbers are hitting fog pretty hard
at all taf sites, but have tempered that back to just tempo/S for
MVFR from 11z-13z. Mixing will start shortly after sunrise,
helping to clear out any fog. High pressure will continue to build
into Illinois on Wednesday, with lower dewpoints hopefully mixing
out some of the residual moisture. Few to scattered cumulus will develop
tomorrow morning, with less cumulus in the east than west. Winds will
remain light east-southeast tomorrow, with speeds less than 10kts.


Ilx watches/warnings/advisories...


Short term...shimon
long term...hjs

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