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fxus63 kilx 200416 
afdilx

Area forecast discussion
National Weather Service Lincoln Illinois
1116 PM CDT Thu Oct 19 2017

Update...
issued at 845 PM CDT Thu Oct 19 2017

Pleasant weather conditions to continue through tomorrow as high
pressure at the surface and aloft hold across the region. A weak
frontal boundary slipped into the far northern part of the
forecast area this afternoon with only a minor wind shift noted.
That boundary will shift back north as the upper level heights
start to build over the Midwest. This will bring a continuation
of the nice weather to our area tomorrow into Saturday before
rain chances increase Saturday night into Sunday. We may see a
bit more in the way of high level clouds stream northeast across
the area on Friday, but that shouldn't have any affect on
afternoon temperatures as readings climb close to the 80 degree
mark over most of our area.

Have made only minor adjustments to the hourly temperature grids,
mainly across the area, but not enough to affect the expected
overnight lows at this point. As a result, no evening zone forecast product update
will be needed.

&&

Short term...(this evening through friday)
issued at 300 PM CDT Thu Oct 19 2017

Nearly ideal fall harvest weather expected to continue across
central and southeast Illinois through Saturday as dry conditions and
above normal temperatures continue. Sunny skies prevailed this
afternoon with lighter winds near 10 mph or less and mild
temperatures in the mid to upper 70s. 1025 mb high pressure was
over the southeast US and ridging into IL/in. Meanwhile an upper
level ridge was building into Illinois from 590 dm 500 mb high over the
north central Gulf of Mexico. Surface high pressure will stay se
of Illinois through Friday while upper level ridge shifts slowly east
over the Ohio River valley. Fair weather will continue with some
passing thin cirrus clouds. Lows tonight mostly in the lower 50s
with winds staying light and some upper 40s from I-57 east. A bit
stronger southerly winds of 8-14 mph with gusts 15-20 mph by
Friday afternoon combined with ample sunshine to warm temps into
the upper 70s most locals with a few cities reaching 80f.

Long term...(friday night through thursday)
issued at 300 PM CDT Thu Oct 19 2017

Strong upper level ridge will be over the eastern states Saturday
while deep upper level trof over The Rockies. Another dry and warm
day on Saturday as skies become partly sunny with highs in the
mid to upper 70s and a few cities near 80f again. 12z models bring
a cold front east toward the Iowa/Illinois border by sunrise Sunday and
have chances of showers and thunderstorms over the Illinois River valley
Sat evening and likely to categorical pops spreading east over County Warning Area
during overnight Saturday night. Cold front to sweep east across
Illinois during Sunday and continues showers, with isolated thunderstorms
south of I-74 Sunday morning. Cooler highs Sunday range from low
to mid 60s over the Illinois River valley, to the upper 60s and lower
70s across eastern Illinois east of I-55.

A cutoff upper level low forms over the southern MS River Valley
Sunday night and then tracks NE into Tennessee/Ohio River valley Monday
keeping chances of showers around the area Sunday night and
Monday especially east of the Illinois River. Highs Monday mostly in the
upper 60s. A deepening upper level trof then digs south-southeast into Illinois
later Monday night and Tue bringing more cooler air along with
continued chances of showers. Highs Tue only in the mid to upper
50s central Illinois and lower 60s in southeast Illinois. Even cooler on Wed
with highs in the low to mid 50s. Tue and Wed nights will be
coolest with lows in the upper 30s to around 40f. Strong upper
level trof starts shifting east of Illinois during Wed but lingers
isolated light rain showers, with dry conditions returning Wed
night and Thu of next week. Highs next Thu moderate into the upper
50s and lower 60s with return of partly to mostly sunny skies.

&&

Aviation...(for the 06z tafs through 06z Friday night)
issued at 1106 PM CDT Thu Oct 19 2017

VFR conditions are expected through Friday night. High pressure at
the surface and aloft will govern our weather for the next 24 to
36 hours. Scattered cirrus will push across the area at times
through the period as a storm system gathers strength well out
to our west and southwest, but no significant cloud cover or
vsby restrictions are expected through tomorrow night. Southerly
winds tonight of less than 10 kts will increase to between 8 and
13 kts on Friday

&&

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

$$

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