Area Forecast Discussion
Issued by NWS Central Illinois

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FXUS63 KILX 250526

Area Forecast Discussion
National Weather Service Lincoln IL
1226 AM CDT Sun Jun 25 2017

Issued at 859 PM CDT Sat Jun 24 2017

A weak cold front trailing a shortwave over Wisconsin will bring a
few showers to areas just north of Knox, Stark, and Marshall
Counties this evening, but it looks like these will stay out of
the central IL forecast area. West to northwest winds have already
diminished to around 5 mph across most of the area, and will shift
more southwesterly just ahead of the feature. As it pulls away to
the northeast late tonight, winds should shift back to WNW. A
pressure gradient across the area should keep winds from becoming
totally calm overnight, therefore limiting lows to mainly mid 50s.
For Sunday, have bumped up afternoon wind speeds/gusts a few mph
with another weak shortwave moving through the area. Only minor
updates for hourly temperatures trends and wind features tonight
through Sunday.


.SHORT TERM...(This evening through Sunday)
ISSUED AT 300 PM CDT Sat Jun 24 2017

Cumulus clouds (more widespread south of I-72 at mid afternoon)
will dissipate around dusk/9 pm leaving fair skies tonight as
breezy WNW winds this afternoon diminish as well by sunset. Lows
in the low to mid 50s overnight expected with a few upper 40s
possible be Galesburg/Knox county.

Sundays weather looks like a repeat of today`s weather and used
persistence for the forecast. Breezy WNW winds expected to develop
again after 9 am Sunday with scattered cumulus clouds as weak
short wave drops se into area. Highs in the mid to upper 70s,
with coolest reading north of I-74 where more cumulus clouds
appear. A 555 dm 500 mb low near Minneapolis MN will track
eastward into southeast Ontario Sunday afternoon keeping its
convection north/NE of CWA.

.LONG TERM...(Sunday night through Saturday)
ISSUED AT 300 PM CDT Sat Jun 24 2017

Another seasonably cool night expected Sunday night with lows
50-55F and a few upper 40s again possible around Galesburg/Knox
county. A stronger northern stream short wave drops se into area
later Monday afternoon and could develop isolated convection over
central IL from mid to late Monday afternoon and shifting into
southeast IL with short wave Monday evening. Monday appears to be
the coolest day in the low to mid 70s with more cloud cover
expected especially Monday afternoon. Cool lows Monday night in
the lower 50s again.

Large upper level trof over the Great Lakes and Ohio river valley
on Monday will shift east toward the mid Atlantic states by sunset
Tue and temps to begin to modify with highs in the upper 70s Tue
(near 80F sw CWA) with a fair amount of sunshine expected.
Dewpoints stay low in the 45-55F degree range through Tue. Not
quite as cool Tue night with lows in the upper 50s eastern IL and
lower 60s western IL as southerly flow develops.

Temperatures warm closer to normal on Wed with highs in the low
to mid 80s and dewpoints rising to 60-65F Wed afternoon (highest
in western IL) with breezy SSW winds developing. Isolated
convection possible nw of the IL river Wed morning and pops
increase to 20-40% north of I-72 during Wed afternoon. This due to
surface low pressure tracking eastward over northern MN/WI by
sunset Wed and its cold front extending sw to a weaker surface low
pressure in western KS. Increasing WAA and weak short waves
ejecting eastward into the IL river valley. Pops increase during
Wed night north of I-70 with likely pops over northern CWA by
overnight Wed night as cold front pushes toward nw IL. Unsettled
wx expected across area Thu-Sat with frontal boundary near area
along with a warm/humid tropical air mass. Highs in the 80s
Thu/Fri and low to mid 80s Sat with dewpoints in the upper
60s/lower 70s and possibly higher at times.


.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1224 AM CDT Sun Jun 25 2017

Winds more southwesterly overnight...becoming more
west/northwesterly in the morning and gusty through the afternoon.
CU quick to develop yesterday and will see that again
tomorrow...with the more dense cu in the northern terminals. VFR




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