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Area forecast discussion 
National Weather Service Lincoln Illinois
255 PM CDT sun Oct 4 2015

Short term...(tonight)
issued at 255 PM CDT sun Oct 4 2015

Upper low storm system over the southeastern this afternoon still
driving the moisture into the Midwest. Although the low and mid
level clouds persisted through the overnight, a wide swath of drying
spread through Ohio and Indiana and is slowly eroding the eastern
side of the cloud shield. Tonights forecast centers on how far
those clouds can erode before sunset and llvl moisture gets trapped
below the inversion. Clear areas to the east may end up seeing more
in the way of patchy fog and cooler temps, but a lot will hinge on
the xover temps and how far back to the east/southeast the stratus redevelops
tonight. Have trended the forecast to the hrrr which has been
handling the erosion of the clouds quite well.


Long term...(monday through sunday)
issued at 255 PM CDT sun Oct 4 2015

Mostly clouds skies will still be lingering over most of central and
parts of eastern Illinois tomorrow, as the upper level low pressure area
in southeast US finally shifts out to sea. This will allow high
pressure ridge to build into the area for the first half of the
week. Winds will remain northeast but begin to decrease in speed
tomorrow and Tuesday, and then become more light and variable for
Wednesday. Dry weather is expected through the short-term period,
and with, hopefully, more sunshine than today, temps should quickly
warm into the 70s for tomorrow through Wednesday.

The next major weather system to bring pcpn to the area will be
later in the week, Thursday through Friday afternoon. The GFS and
European model (ecmwf) have come into better alignment with the timing of the front,
and it should move through the area Thursday night. So am expecting
light pcpn thur morning in the west/northwest, with it then
spreading east during the day, and then continuing across the County Warning Area
Thursday evening. Pcpn should begin ending from west to east late
Thursday night and then continue through Friday morning. Temps will
be above normal for Thursday, but once the front and pcpn move
through, temps will fall back into the 60s across most of the area.
This, however, will temporary as 70s should return for the end of
the weekend.


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1239 PM CDT sun Oct 4 2015

Hrrr is very optimistic in clearing the conditions across central
Illinois, considering the continued northeasterly fetch to the
winds. However, it is also handling the clearing in the southeast
properly. Inclined to follow along at least as far as the early
afternoon. Main concern is how much mixing can occur to help erode
cloud cover before sunset and the inversion traps the moisture in
the low levels. Keeping it conservative for now... with VFR this
afternoon in the east, dropping to IFR overnightfor bmi pia and
spi deeper into the moisture. Confidence is low and changes are
anticipated as the sun sets and with the 00z sounding.


Ilx watches/warnings/advisories...


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

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