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Area forecast discussion 
National Weather Service Lincoln Illinois
1103 am CST Wednesday Nov 25 2015

issued at 1058 am CST Wednesday Nov 25 2015
high pressure sliding off to the east while the next storm system
spins up over the Southern Plains. A quick wave moving up through
the upper Midwest bringing some light sprinkles with some of the
clouds this morning. Not measurable, but possibly enough to wet
pavement. Cloud bases relatively high this morning, but steadily
moving into the area. Not a lot of changes for the forecast
overall, but a mention of sprinkles moving up the I-55 corridor
for the rest of today ahead of the approaching showers later


Short term...(today)
issued at 330 am CST Wednesday Nov 25 2015

The County Warning Area is in between the high pressure to the east and the
developing weather system in the plains. In this position, breezy
southerly winds and warmer temperatures are to be expected today.
With the increasing waa ahead of the developing system, an increase
in low level moisture is occurring, which is will bring an increase
in cloud cover to the area. The increasing clouds could retard the
warming trend this afternoon, but believe the strong waa should be
able to compensate. So, am expecting skies to become mostly cloudy
today with highs in the 50s and southerly winds of 15 to 25 mph.

Long term...(tonight through tuesday)
issued at 330 am CST Wednesday Nov 25 2015

00z models are similar with cold front moving east into the Illinois River
valley Thu night and across eastern Illinois Friday afternoon. Aloft,
strong 538 dm 500 mb low over northern California into NW Nevada will move
across the central rockies on Thu and remain near The Rockies this
weekend and eject NE into the Midwest and Great Lakes on Monday
night and Tue. This will likely bring an extended unsettled weather
pattern to Illinois with daily rain chances through early next week.

Chances of light rain showers moves into the Illinois River valley this
evening and deeper into central Illinois overnight while southeast Illinois
remains dry. Milder lows tonight in the upper 40s to around 50f with
clouds and breezy south winds. Clouds and breezy south winds
continue Thu with highs in the upper 50s and lower 60s. Rain chances
also increase to 60-80% NW of the Illinois River by Thu afternoon and 40-
50% over heart of central Illinois while only 20-30% in southeast Illinois and
near the in border. Rainfall amounts even NW of the Illinois River appear
fairly light on Thu with highest amounts near a quarter inch by

Increased lift with approaching cold front and deeper moisture to
bring highest rain chances Thu night into Friday along with heaviest
rainfall ranging from 1-1.5 inches with rain chances likely
lingering over southeast Illinois Friday night where storm total rainfall
of 1.50-1.75 inches. This may cause some rivers and streams to go
back to near flood especially at Clay City on the Little Wabash
River. Flash flood guidance is 1.5-2 inches per hour and 2-3 inches
in 6 hours so these rainfall amounts are still less than that and
will hold off on a Flood Watch.

Surface low pressure to lift NE along frontal boundary just
southeast of the Ohio River into NW Kentucky by Sunday morning. This will
likely lift showers back NE into central Illinois during this weekend
especially Sat night into Sunday morning. Highest rain chances will
be over southeast Illinois along with heaviest rainfall amounts. Even
though temps cool by this weekend, they still appear warm enough to
support rain over our area. Lingered 20-30% chances of light rain
showers early next work week as upper level low moves into the area
and keeps it cloudier and cooler.


Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 524 am CST Wednesday Nov 25 2015

Clear skies will give way to clouds around 5kft moving into the
area this morning. The clouds will begin in the west at spi and
pia, then spread east and reach cmi last. Based on satellite
trends and upstream observations, looks like heights will remain
VFR levels, around 3.5kft. The clouds will continue through the
day and into the night ahead of the next weather system. Hrrr and
nam12 bring some light/scattered pcpn into the area beginning
late this afternoon and into tonight. Given the waa and all the
clouds, though not that low, will go with vcsh at all taf sites in
the new forecast for late this afternoon and into this evening.
Winds will be southerly through the period with daytime gusts to
around 25kts. Winds will decrease some during the evening, but
expecting gusts to continue.


Ilx watches/warnings/advisories...


short term...auten
long term...07

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