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Area forecast discussion 
National Weather Service Lincoln Illinois
617 am CDT Sat may 23 2015

Short term...(today)
issued at 342 am CDT Sat may 23 2015

High pressure centered well east of the area will still have
some influence on the weather across the area today...with dry and
warm conditions. Upper level low pressure area in the southwest US
will keep southwest flow across the plains and middle level ridging
over the Midwest. Middle and upper level moisture associated with any
little wave in the southwest flow will lift northeast but remain
west of the area. Clouds associated with any of these waves will
continue to spread across the County Warning Area today. Clouds usually keep temperatures
on the cooler side...but with southerly winds to compensate for the
clouds...and 850mb temperatures same as yesterday...expecting high temperatures
today to be around the same as yesterday...upper 70s to around 80.

Long term...(tonight through friday)
issued at 342 am CDT Sat may 23 2015

High pressure ridge losing ground to approaching system from the
west. Tonight expected to be a little warmer as cloud cover and a
southerly component to the winds overnight limit the amount of
cooling. Precipitation from the approaching storm has been wavering with
its arrival time going slower on 00z runs and faster with the 12z
runs of operational models. Tonight was no different slowing the
onset of precipitation in the far western portions of the County Warning Area until right
around 12z Sun morning. Southerly flow continues to feed warm air
and moisture up into the region and the models keep the precipitation in
for a while with a more active southwesterly flow aloft. Better
chances for precipitation accompany the main energy moving into the Midwest
Sun night and into Monday. Models have pretty good continuity with
a dry slot developing Monday afternoon and into the overnight hours,
and have pulled back the probability of precipitation for that time frame accordingly,
though not entirely ready to pull them out completely with the
potential for any clearing reenergizing the atmosphere for afternoon
convection on any mesoscale boundary.

In the longer term, forecast continues warm and rainy with
unsettled weather on the edge of weak southwesterly flow aloft.
Midwest remains in the path of several vorts moving out of the
deeper low/trough sitting over the southwestern Continental U.S.. deep layer
shear still limited with weak flow aloft, but hot and muggy airmass
will continue to feed into the region and models are more than
generous with the convection through the end of the forecast. That
being said, Wednesday night through Thursday night remain the lowest probability of precipitation in
the forecast with a weak ridge briefly moving in between systems.

&&

Aviation...(for the 12z tafs through 12z Sunday morning)
issued at 617 am CDT Sat may 23 2015

VFR conditions will prevail at all taf sites next 24hrs. Broken
middle clouds have overspread the area and will continue into the
afternoon. Scattered lower clouds around 5kft will advect into the
area this afternoon and then become overcast this evening around
00z and then last until 12z tomorrow. Could be some precipitation moving in
late tonight but 06z models have slowed onset of precipitation at western
taf sites until after 12z tomorrow. Winds will be light this morning
and then become southerly around 10kts. This evening winds will
shift to southeast.

&&

Ilx watches/warnings/advisories...
none.
&&

$$

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

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