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FXUS63 KILX 052342
AFDILX

Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
642 PM CDT Wed Jun 5 2024

.KEY MESSAGES...

- A departing cold front will trigger scattered showers and
  thunderstorms across east-central Illinois this afternoon into
  early this evening...with the highest probability of rain
  focused along/east of I-57.

- Below normal temperatures will prevail through the entire
  forecast period. Daily high temperatures will remain in the
  75-80 degree range and overnight lows will drop into the 50s
  Thursday through Monday.

&&

.SHORT TERM...(Tonight through Thursday)
Issued at 220 PM CDT Wed Jun 5 2024

1830z/130pm surface analysis shows a cold front just east of I-55.
A narrow band of showers is trying to develop immediately along
the front, while scattered showers/thunder linger further east in
the Wabash River Valley. The front will continue to push slowly
eastward for the balance of the afternoon, with the areal coverage
of showers gradually increasing. Based on the latest satellite/radar
trends as well as the 17z HRRR, it appears coverage will become
greatest along/east of a Danville to Effingham line...with the
precip pushing into Indiana and exiting the far E/SE KILX CWA by
around 00z/7pm.

Once the front passes, skies will clear from west to east across
the area this afternoon/evening. Meanwhile a secondary cold front
analyzed upstream across the Northern Plains will dip into
Illinois tonight. CAMs continue to suggest isolated showers along
the boundary across the far north later this evening before
daytime instability wanes and any lingering showers dissipate
overnight. Have included slight chance PoPs along/north of a
Macomb to Bloomington line accordingly.

As high pressure builds into the Plains and the pressure gradient
tightens, gusty NW winds will develop in the wake of the secondary
front on Thursday. NAM forecast soundings suggest deep-layer
mixing up to 7000-8000ft, which will tap into winds of 40-45kt.
This will lead to surface gusts of 25-30mph. Aside from the winds,
it will be a sunny and pleasant day with highs in the upper 70s
to around 80 degrees.

Barnes

.LONG TERM...(Friday through Next Wednesday)
Issued at 220 PM CDT Wed Jun 5 2024

Abundant sunshine, mild temperatures, and low relative humidity
values will continue into Friday before the next potential
weather-maker spreads clouds and perhaps a few showers into the
region on Saturday. The synoptic pattern will be dominated by an
unseasonably deep upper-low anchored over Ontario and the Great
Lakes and a strong high over the Desert Southwest into the
Southern Plains. Central Illinois will remain sandwiched between
these two features embedded within deep-layer northwesterly flow.
Nocturnal MCS activity will fire along the N/NE periphery of the
upper high both Friday night and Saturday night: however, all
models continue to indicate this convection will remain well S/SW
of central Illinois from Kansas southeastward into the Ozarks.
Meanwhile further north, a weak short-wave trough pivoting along
the southern flank of the upper low may skirt close enough to
central Illinois to bring a few showers...particularly during peak
heating Saturday afternoon/evening. Have therefore added slight
chance PoPs for showers/thunder everywhere east of the Illinois
River.

All solutions suggest the upper trough will deepen further early
next week, ensuring the continuation of cool and largely dry
conditions. High temperatures will remain in the 70s and overnight
lows will dip into the 50s through Monday before upper heights
begin to rise and temps moderate back closer to normal by the
middle and end of next week.

Barnes

&&

.AVIATION...  (For the 00z TAFs through 00z Thursday Evening)
Issued at 636 PM CDT Wed Jun 5 2024

A cold front has pushed across central Illinois already today, but
another weak front currently over WI/IA will pass through central
Illinois late tonight. WNW winds currently in place will back to
the SW ahead of the approaching front, then veer to the WNW late
tonight as the second front passes through. Expect only mid-level
clouds with frontal passage with precip unlikely. NW winds will
gust to 20-25kt starting mid to late Thursday morning and continue
through sunset Thursday evening. VFR conditions will prevail
through the period.

Deubelbeiss

&&

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

$$