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afdilx

Area forecast discussion
National Weather Service Lincoln Illinois
1038 am CST Fri Nov 24 2017

Update...
issued at 1033 am CST Fri Nov 24 2017

Low pressure system moving into the Great Lakes this morning, and
a cold front is approaching the Midwest. Ahead of the boundary,
however, winds remain out of the south/southwest. Winds are
expected to be a little breezy today with an increasing pressure
gradient under the deepening low. Sunshine in advance of the
front, in concert with the warm air advection in the region will
result in a rather warm day, and highs will climb into the 60s.
Forecast in general is doing well and no major updates are
anticipated.

&&

Short term...(today and tonight)
issued at 330 am CST Fri Nov 24 2017

A mild and windy day is ahead of central and southeast Illinois with
mostly sunny skies as some high clouds pass by. South-southwest winds
increasing to 15-20 mph will gust 25-35 mph by afternoon, with
1020 mb high pressure over the southeast states and strong 987 mb
low pressure over west central Ontario tracking toward the
southern tip of James Bay Canada by sunset. This will help warm
temps into the upper 50s east of I-57 and mid to upper 60s from
Peoria and Springfield west toward the MS River Valley.

As the low pressure moves into northern Quebec tonight, it will
sweep a cold front se through Illinois tonight. The brunt of moisture
and lift still appears to pass NE of central IL, and just have
mention of sprinkles this evening, and lingering over southeast Illinois
early overnight. Lows in the upper 30s and lower 40s overnight.

Long term...(saturday through thursday)
issued at 330 am CST Fri Nov 24 2017

High pressure to settle into the Central Plains on Saturday while
upper level trof shifts east of IL, into the central Great Lakes
and eastern Ohio River valley by sunset Sat. After a period of
clouds with cold front tonight, expect return of mostly sunny
skies on Saturday. Cooler highs of 50-55f with coolest readings
from I-74 NE. These readings are still above normal highs in the
mid to upper 40s for late November. Lows Sat night mostly in the
lower 30s, with a few upper 20s northern County Warning Area. High pressure
extends from Texas into the mid MS River Valley on Sunday and
provides ample sunshine again with highs back in the low to mid
50s, with upper 50s in west central Illinois.

High pressure sprawled across the southeast states on Monday while
986 mb low pressure moves east over the central Canadian prairies.
Another breezy day on Monday and south-southwest winds to help moderate temps
back up into the upper 50s and lower 60s and similar readings on
Tue, maybe a degree or two cooler over NW County Warning Area as a cold front
moves into the Illinois River valley late in the day Tue. Isolated light
rain showers possible northern County Warning Area late Tue afternoon into Tue
evening but most of County Warning Area should stay dry thru Tue night.

ECMWF, GFS and Gem models eject a mid/upper level low/trof into
the Central Plains by midday Wed and moving near Illinois Wed night.
Models still have some differences with handling position of this
system as Gem model is further south while European model (ecmwf) model continues
to be slowest with this wx system. Stayed close to consensus for
slight pops of rain showers Wed afternoon over all but east
central Illinois. Then have 20-30% pops of mainly rain showers Wed
night, though could be mixed with light snow overnight Wed night
NW of Illinois River. Have 20-30% pops from I-55 east Thu morning then
dry. Temps cool closer to normal during 2nd half of next week with
highs in the mid to upper 40s Wed-Fri, except lower 50s in
southeast Illinois Wed/Thu.

&&

Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 555 am CST Fri Nov 24 2017

VFR conditions are expected to continue across the central Illinois
terminals through 12z/6 am Saturday. 1019 mb high pressure
stretching from the mid Atlantic states SW into southeast Texas
will stay over the southeast states next 24 hours, while 986 mb
low pressure over west central Ontario tracks east into NW Quebec
overnight tonight. This will pull a cold front over the northern
plains se through central Illinois from 04-08z tonight. Scattered cirrus
clouds will occur today, with scattered mid and broken high
clouds this evening and possible sprinkles, then decreasing
behind cold front overnight. Low level wind shear will be confined to areas NW of
the Illinois River/pia into mid morning. South-southwest winds 5-10 kts at dawn will
increase to 15-20 kts by late morning and gusts 22-29 kts by
midday and through the afternoon. Winds veer SW and decease to 10-15
kts after dark and could still be gusty early this evening. Winds
shift NW behind the cold front at speeds of 7-12 kts overnight.



&&

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

$$

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