233
FXUS63 KILX 091054
AFDILX

Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
554 AM CDT Thu May 9 2024

.KEY MESSAGES...

- Cooler weather is on tap for the end of the week with overnight
  lows dipping into the 40s tonight through Saturday night.

- The next significant chance for widespread showers and
  thunderstorms will hold off until early next week.

&&

.SHORT TERM...(Today through Friday)
Issued at 334 AM CDT Thu May 9 2024

Low pressure currently centered over central Illinois will track
slowly eastward today. Despite rising surface pressures, a trailing
upper trough extending from the Great Lakes into the Plains will
sink southward...providing synoptic lift for scattered showers.
May see a couple thunderstorms as well, as NAM MUCAPE values
exceed 1000J/kg from late morning through the afternoon. High
temperatures will mainly be in the middle to upper 60s, but will
reach the lower to middle 70s along/south of I-70 where partial
sunshine will be observed. Widely scattered showers will persist
tonight as the trough drops into central Illinois. Overnight lows
will dip into the 40s. As the wave gradually departs, synoptic
subsidence on its back side will provide partial clearing and dry
weather on Friday with highs remaining in the middle to upper 60s.

Barnes

.LONG TERM...(Saturday through Wednesday)
Issued at 334 AM CDT Thu May 9 2024

Another short-wave trough evident on latest water vapor imagery
over northern Alberta/Saskatchewan will drop southeastward into
the Great Lakes Friday night into Saturday. While the strongest
lift will remain N/NE of central Illinois, scattered showers will
be possible across the N/NE KILX CWA Friday night...with the
showers pushing further east into Indiana by Saturday. Generally
dry weather is expected over the weekend...with highs around 70
on Saturday climbing into the middle to upper 70s by Sunday.

A cut-off upper low spinning over the Great Basin will gradually
get shunted northeastward early next week, with models showing
typical timing differences at this range. Based on consensus,
think the low will slowly approach from the southwest and begin to
impact the weather across central Illinois by late Monday. As the
feature gets closer and deep-layer moisture increases, showers and
thunderstorms will become likely Monday night into Tuesday.

Barnes

&&

.AVIATION...  (For the 12z TAFs through 12z Friday Morning)
Issued at 554 AM CDT Thu May 9 2024

Low pressure centered near KBMI at 1030z/530am will track slowly
eastward today. Winds to the south of the low track at the I-72
terminals will initially be W/SW early this morning, then will
veer to NW and gust 15-20kt by midday as the low moves further
away. Meanwhile at KPIA/KBMI light/variable winds will veer to
N/NE. Scattered showers/thunder associated with a trailing upper
trough will develop southward as the day goes on, so have included
VCSH at all sites during the afternoon into the early evening.
Ceilings have become MVFR across the board this morning, but may
scatter at both KSPI and KDEC toward midday as per HRRR guidance.
Any ceiling improvement will be short-lived however, as MVFR
clouds will return once winds become more northerly this
afternoon.

Barnes

&&

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

$$