994
FXUS63 KILX 011735
AFDILX

Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
1235 PM CDT Tue Oct 1 2024

.KEY MESSAGES...

- Breezy conditions will continue behind a departing cold front
  this afternoon. Northwest winds will gust between 20 and 30 mph
  through early afternoon.

- As winds subside, low temperatures tonight will dip into the
  lower to middle 40s.

- An extended period of dry weather is expected today through next
  Monday.

&&

.UPDATE...
Issued at 1036 AM CDT Tue Oct 1 2024

A dry cold front continues to push out of the area this morning,
with winds already shifted to northwesterly at Lawrenceville and
becoming gusty as pressure gradients and brisk winds aloft build
into the area behind the front and ahead of a high pressure
center currently over Nebraska. Gusts in the 20 mph range with a
few exceeding 30 mph look on track for late this morning into
early afternoon, then should start weakening by late afternoon as
the high rapidly approaches. Temperatures will be down several
degrees for most areas north of I-72, with highs near 70, and to
the south highs will range up to near 80 for early afternoon
highs south of I-70. No significant updates were needed this
morning as the morning forecast package incorporates these
features well.

37

&&

.SHORT TERM...(Today through Wednesday)
Issued at 321 AM CDT Tue Oct 1 2024

08z/3am surface analysis shows a cold front approaching the Illinois
River. Based on timing tools, the front will reach I-55 by 6am and
I-57 by around 8am. Winds ahead of the front are SW at around
5mph:however, they veer to NW and increase markedly immediately behind
the front...with gusts of 25-30mph common across Iowa. Forecast
soundings indicate post-frontal mixing up to around 4000ft later
this morning into the afternoon, suggesting the potential for even
higher gusts. The 00z Oct 1 LREF shows nearly a 100% chance of
wind gusts over 25mph everywhere north of the I-70 corridor and a
high probability (50-70%) chance of gusts in excess of 30mph
along/north of a Macomb to Bloomington line. Thanks to strong CAA
courtesy of the gusty NW winds, temperatures will be several
degrees cooler than yesterday with afternoon highs ranging from
around 70 degrees in the Illinois River Valley to 80 degrees far
southeast at Lawrenceville.

High pressure will build into the region tonight, resulting in
clear skies and diminishing winds. With the ridge axis directly
overhead by 12z Wednesday, optimal radiational cooling conditions
of the very dry airmass will allow overnight lows to dip into the
lower to middle 40s. Probabilities for readings cooler than 40
degrees have decreased from previous model runs...with only a few
pockets of less than 10% probs north of the I-72 corridor. After a
chilly start to the day, full sunshine will efficiently heat the
atmosphere into the lower 70s by Wednesday afternoon.

Barnes

.LONG TERM...(Thursday through Monday)
Issued at 321 AM CDT Tue Oct 1 2024

Quiet weather will prevail throughout the extended as a zonal flow
pattern establishes itself across the CONUS. Once surface high
pressure shifts off to the east, increasing southwesterly boundary
layer flow will allow temperatures to quickly rebound into the
upper 70s to around 80 degrees Thursday through Sunday. After
that, another short-wave trough traversing the U.S./Canada border
will push a dry cold front through central Illinois Sunday
night...dropping temps back into the lower 70s by next Monday.

Barnes

&&

.AVIATION...  (For the 18z TAFs through 18z Wednesday Afternoon)
Issued at 1235 PM CDT Tue Oct 1 2024

VFR conditions will continue for the upcoming 24 hours as a cold
front pushes farther east of the area, and high pressure settles
over the area tonight. NW winds 12-18 kts with gusts 20-26 kts
early this afternoon, decreasing to light and variable by 06Z.

37

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$