328
FXUS63 KILX 301539
AFDILX

Area Forecast Discussion
National Weather Service Lincoln IL
Issued by National Weather Service Chicago IL
1039 AM CDT Tue Apr 30 2024

.KEY MESSAGES...

- Above normal temperatures will prevail across the area through
  next Tuesday May 7th, with Thursday being the warmest day with
  highs in the low to mid 80s and windy with southerly winds
  gusting 25-35 mph by Thu afternoon.

- There is a chance of showers and thunderstorms late this evening
  and overnight, mainly over the IL river valley where a marginal
  risk of severe storms for gusty winds and hail west of the IL
  river from 10 pm to 2 am tonight. More widespread showers and
  thunderstorms with heavier rains expected Thursday afternoon
  into Friday morning.

&&

.UPDATE...
Issued at 1038 AM CDT Tue Apr 30 2024

Fog over southeastern portions of the CWA has burnt off and
allowed dense fog advisory to expire as scheduled. Current
forecast is in good shape with no updates planned for this
afternoon`s forecast. Will be assessing the threat of showers
and storms for tonight with the afternoon forecast.

- Izzi

&&

.DISCUSSION...
Issued at 400 AM CDT Tue Apr 30 2024

A weakening cold front had pushed southeast of IL early this
morning with its convection now mainly southeast of Indiana over
western Ohio, central KY and mid TN. Lingering stratus clouds
lifting NNE over Wabash river valley of southeast IL se of a
Danville to Flora line. Widespread fog from Danville to
Shelbyville southeast with dense fog common from Paris to
Charleston/Mattoon to Shelbyville southeast where dense fog
advisory continues through 9 am today. The fog should lift by mid
morning in southeast IL with the stratus clouds scattering out
over the Wabash river valley during this morning. Weak high
pressure over IL early this morning to drift east over the Ohio
and TN river valley this afternoon, with south to SW winds
increasing and approaching breezier levels later today over the IL
river valley. A very nice day expected overall with ample sunshine
with highs in the mid to upper 70s and more comfortable dewpoints
in the 50s.

A weather system over MT and WY early this morning to track
eastward into the upper MS river valley by midnight and have a
cold front approaching nw IL, and moving through central IL
overnight as it weakens. Have a better chance of showers and a few
thunderstorms by late evening over the IL river valley, with these
chances diminishing at it shifts into east central IL overnight.
SPC day1 outlook has marginal risk of severe storms late this
evening and early overnight from the IL river west for gusty
winds and hail, while tornado threat and greater risk of severe
storms is west of IL this evening. Southeast IL will likely stay
dry tonight. Lows overnight in the upper 50s to around 60F.

Another weak high pressure ridge over IL on Wed with upper level
ridging into the Ohio and TN river valleys. This to bring fair wx
and lighter winds on Wed with skies becoming partly sunny. Warm
highs Wed in the upper 70s central IL and lower 80s in southeast
IL. A warm front lifting northward over central IL overnight Wed
night into Thu morning could bring isolated convection Wed night
into Thu morning especially from I-55 west. Will see higher
chances of showers and thunderstorms later Thu west of the IL
river ahead of approaching storm system from the central plains.
Breezy southerly winds develop in warm sector on Thu with gusts
25-35 mph likely by Thu afternoon. This to bring warm highs in the
low to mid 80s, a bit shy of record highs in the lower 90s on May
2nd. Surface low pressure developing over southeast CO by sunset
Wed to eject ne toward the MN/WI/IA border by sunset Thu and pull
a cold front east through central IL during Thu night, and thru
southeast IL Fri morning. This front to likely bring showers and
thunderstorms eastward over the IL river valley late Thu afternoon
into Thu evening and across rest of central IL during Thu night.
Best chances for convection in southeast IL is late Thu night into
Friday. SPC day3 outlook for Thu/Thu night keeps marginal risk
west of CWA, except reaching near Galesburg by Thu evening. WPC
has slight to marginal risk of excessive rainfall over IL Thu
night with higher rainfall amounts expected over the IL river
valley where over 1 inch expected.

Convection chances to diminish behind the cold front from west to
east during Friday, with chance of showers possibly lingering into
Fri evening over southeast IL. Highs Friday in the lower 70s in
central IL and mid 70s in southeast IL. Models still not in the
best agreement with the weekend forecast as blended models now
giving a chance of showers and isolated thunderstorms on Saturday
afternoon and Sat night which was dry with yesterdays runs. And
latest trends for chances of shower and thunderstorms on Sunday
have lowered and shifted southward. Highs this weekend in the 70s
with southeast IL near 80F on Saturday.

07

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1036 AM CDT Tue Apr 30 2024

(For the 12z TAFs through 12z Wednesday Morning)
Issued at 555 AM CDT Tue Apr 30 2024

Patchy fog just developed at CMI airport with vsby 1.5 miles. This
patchy ground fog should lift in next 1-2 hours, with generally
VFR conditions forecast to prevail across the central IL airports
through 12Z/7 am Wed. A cold front approaching tonight will bring
a band of showers and isolated thunderstorms to PIA/IL river late
this evening, to I-55 by 05-06Z and possibly as far as DEC and CMI
by 07Z as it weakens. Could briefly be MVFR conditions if
thunderstorms occur which look more favorable at PIA from 04-06Z.
Light and variable winds early this morning to become SW near 10
kts by late morning/afternoon and increase to 10-15 kts with gusts
18-23 kts later this evening and overnight.

07

&&

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

&&

$$