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Area forecast discussion 
National Weather Service Lincoln Illinois
520 am CST Wed Jan 28 2015

Short term...(today)
issued at 509 am CST Wednesday Jan 28 2015

Latest surface analysis indicates high pressure just off to our east
which is expected to shift further away from our area during the
day. The next weather system is forecast to push into the Central
Plains today and the tightening pressure gradient between the
departing high and approaching storm will help to increase surface
winds later this morning over west central Illinois and further east
into the remainder of the forecast area this afternoon. Models
indicating an increasing southeast to south flow today with the
better low level warm advection pointed towards west central
Illinois where afternoon temperatures will approach 50 degrees in
our far western and southwestern counties. Meanwhile, over far
eastern Illinois, with more of a southeasterly trajectory in the
surface flow, temperatures will struggle to reach 40 this afternoon.
Rap and hrrr forecasts showing gusts of 30 to 35 mph possible in the
west later this morning and this afternoon, and over all but far
southeast Illinois this afternoon.


Long term...(tonight through tuesday)
issued at 509 am CST Wednesday Jan 28 2015

Surface low pressure close to 1005 mb tracks east-northeast near southern Iowa/MO
border this evening, into northeast Illinois by dawn Thu, and into eastern
lower Michigan by 18z/noon Thu. This to bring a cold front east across Illinois
overnight and into central Indiana by midday Thu. Strong low level
jet with 850 mb winds 40-50 kts to continue gusty winds tonight, then
gusty south winds turn west-northwest behind cold front Thu. Not much moisture
to work with so still think just small chances of light rain over
central and eastern Illinois overnight into Thu morning. Lows tonight in
mid to upper 30s with coolest readings in eastern Illinois. Highs Thu in
upper 30s from I-74 north and mid 40s in southeast Illinois with temps
likely slipping behind cold front during afternoon.

1035 mb Canadian high pressure drops down into the western Great
Lakes region by sunset Friday and brings cooler and drier weather
from Thu night through Saturday morning as winds diminish. Highs
Friday 30-35f with coldest readings from I-74 north. Lows Thu night
and Friday night in upper teens and lower 20s (except mid 20s in
southeast Illinois Thu night).

00z models continue to trend of phasing northern and southern stream
system and toward a potentially high impact and fairly long duration
weather event from Saturday night through Sunday evening. Surface
low pressure to deepen northeast from south Texas into the eastern
Ohio River valley Sunday night. Most of Saturday looks dry with just
small chances of light precipitation west of I-55 Sat afternoon. Best
chances of snow spreads NE across central/se Illinois Saturday night and
Sunday and then diminishes from the west during Sunday night. Added
a mix of precipitation in far southeast Illinois near Highway 50 Sat night
and Sunday. Potential is there for several inches of snow over parts
of County Warning Area especially se of the Illinois River with qpf of half to three
quarter inches and heaviest in southeast Illinois. Arctic air to follow
this low pressure system early next week with temperatures well
below normal, which we have not experienced since Jan 14th. Highs
Mon/Tue may stay in the teens over northern counties with lows
Monday night reaching near or just below zero from I-74 north.


Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 515 am CST Wednesday Jan 28 2015

Main concern today will be with gusty southeasterly winds as a
storm system approaches from the west. Last of the MVFR cigs
has pushed north of the taf sites so am expecting mainly VFR
conditions today. Forecast soundings suggest the potential for
few-sct clouds at 2500 to 3500 feet, with some higher level
clouds 20000-25000 feet streaming southeast into the area from
time to time. Look for southeast winds to increase to between
15 to 20 kts later this morning into this afternoon with a few
gusts around 30 kts at times into this evening. Winds should
tend to become more southerly this evening as the low pressure
system moves across the area, and then southwest after 03z.
No precip is expected thru the forecast period with some threat
for light rain and possibly MVFR cigs just after this forecast
period Thursday morning.


Ilx watches/warnings/advisories...


Short term...Smith
long term...07

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