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Area forecast discussion 
National Weather Service Lincoln Illinois
652 am CDT Friday may 22 2015

Short term...(today)
issued at 331 am CDT Friday may 22 2015

A beautiful Spring day expected today across Illinois with a fair amount
of sunshine and fairly light winds and mild highs in the middle 70s. A
weak frontal boundary near I-88 in northern Illinois early this morning
will drop southward across central Illinois during this morning and
through southeast Illinois during the afternoon. Little if any lift or
moisture to work with so expect this front to shift be accompanied
by a weak wind shift from the SW to the northwest. Cirrus clouds to
increase from the west later this morning and afternoon as sunny
skies this morning become partly to mostly sunny in the afternoon.
Nudged highs up slightly today into the middle 70s across much of the
area with areas from I-74 NE slightly cooler.

Long term...(tonight through thursday)
issued at 331 am CDT Friday may 22 2015

Nice weather to continue across Illinois during the first half of the
Memorial Day weekend as dry conditions persist through Saturday.
High pressure drifts southeast from Lake Superior into the Middle Atlantic
States Saturday while upper level ridge noses into the MS River
Valley. This to maintain dry conditions tonight and Saturday across
central and southeast Illinois. Middle and high clouds continue to increase
tonight and Saturday with skies trending toward partly to mostly
cloudy. Lows tonight in the low to middle 50s with highs Sat in the middle
to upper 70s.

Large upper level trough/low digging over The Rockies during this
weekend to eject short waves NE into the Central Plains Sat night
and into the upper MS River Valley on Sunday. Surface low pressure
emerges over the Central Plains Sunday and lifts up into the upper
MS River Valley and northern plains Monday. A warm front to lift
northward across central Illinois Sunday morning. This to bring a chance
of showers and thunderstorms to western areas overnight Sat night
and then likely chances west of I-57 Sunday and Sunday night and 40-
50% chance over eastern Illinois Sunday from I-57 east. More humid on
Sunday as warm front lifts north with southerly flow developing as
dewpoints elevate into the middle 60s by Sunday afternoon with highs in
the upper 70s central Illinois and near 80f in southeast Illinois. Storm Prediction Center keeps
marginal risk of severe storms SW of central Illinois Sunday afternoon and
evening where better instability will be during peak heating.

Extended models continue an unsettled weather pattern through much
of next work week with daily chances of showers and thunderstorms as
frontal boundary stays northwest of Illinois through at least Wednesday and possibly
longer. Continue likely chances of showers and thunderstorms Monday
with highs around 80f and dewpoints in the middle to upper 60s. Breezy
conditions expected Monday similar to Sunday in the warm sector.
Continued good chance of showers and thunderstorms during middle of
next week and warm highs in the lower 80s and lows in the middle to
upper 60s. CPC 8-14 day outlook from may 29 through June 4 continues 40-
50% chance of above normal temperatures and precipitation. So a
warm and wet pattern looks to continue into the first week of


Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 652 am CDT Friday may 22 2015

VFR conditions are expected at all taf sites next 24hrs as
predominant subsidence resides over central Illinois with high pressure
building into the area. Winds will be variable...then become NE at
4-8 kts after a weak dry cold front pushes through the area from
the north.


Ilx watches/warnings/advisories...


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

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