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Area forecast discussion 
National Weather Service Lincoln Illinois
605 PM CDT Fri Oct 31 2014

Short term...(tonight)
issued at 304 PM CDT Friday Oct 31 2014

Increased pressure gradient behind the cold front has created a
blustery day across central Illinois. In combination with colder
air moving into the region, wind chills are dropping in the 30s.
Although the winds are expected to slowly decrease after
will be very slow and accompanied by dropping temperatures as well.
As a result, going into Halloween night, trick or treaters will
encounter temperatures in the upper 30s and lower 40s...with winds
still in the 20 to 25 mph range and occasionally very gusty early.
Wind chills at or below freezing for the few hours around sunset.
Temperatures tonight will drop mainly into the 20s and provide a
significant hard freeze for the end of October. Though there is
some spread in the MOS for this event, vast majority keep the 20s in
place. Some remaining lake effect snow/rain will dwindle into the
overnight hours, mainly impacting the extreme eastern Illinois/in border
with flurries and light rain. Accumulations are not expected.


Long term...(saturday through friday)
issued at 304 PM CDT Friday Oct 31 2014

Cold high pressure will settle over Illinois during the day Saturday
bringing much lighter winds, continuing through Saturday night. The
light winds and dry air mass will allow for another night of sub
freezing temperatures due to good radiational cooling. Temperatures
will moderate somewhat Sunday, but still remain much below average
with highs mainly in the upper 40s.

More unsettled weather is on track Monday to Wednesday as moist
southwesterly flow develops ahead of a strong upper level trough
digging into the southern rockies. A frontal boundary will set up
from the Southern Plains NE into the Ohio River valley Monday night
through Wed to bring chances for showers, especially Monday night
and Tuesday. Milder temperatures can be expected in this time
period, with highs in the upper 50s and lows mainly in the 40s.
Model data indicates weak instability with this system, meaning
thunderstorms are unlikely. Drier weather is expected Wed night thru
Friday as dry west northwesterly flow trails the system. Expect
seasonable highs generally in the mid to upper 50s.


Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 600 PM CDT Friday Oct 31 2014

Most areas should see VFR conditions this period. The only
exception will be kbmi and kcmi where some clouds moving
south-southwest off of Lake Michigan may affect those two
sites for most of this evening, and possibly during the
early morning hours. Broad north to northeast flow off the
warm waters of Lake Michigan will continue to stream clouds
into parts of east central Illinois into Saturday morning
before the flow shifts the bulk of the clouds east of our
area. Surface winds will gradually diminish overnight,
especially the gusts from the north and northwest. By
morning, areas along and east of i55 will see northerly
winds at 10 to 15 kts, and further west, winds should be
northerly at around 10 kts most of the day.


Ilx watches/warnings/advisories...
freeze warning from midnight tonight to 9 am CDT Saturday for



Short term...hjs
long term...Onton

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