190
FXUS63 KILX 281946
AFDILX

Area Forecast Discussion
National Weather Service Lincoln IL
246 PM CDT Sat Jun 28 2025

.KEY MESSAGES...

- Very warm and humid conditions persist through Monday, then a
  cold front will usher in seasonable temperatures and humidity
  levels.

- Isolated showers and thunderstorms are possible into early
  evening south of I-72. A better chance for precip exists area-
  wide late Sunday night into Monday (50-80% chance) as a cold
  front moves in. A few strong to severe storms with gusty winds
  could occur.

&&

.DISCUSSION...
Issued at 245 PM CDT Sat Jun 28 2025

A weak boundary lingered over central parts of IL/IN with isolated
convection south of I-72. Unstable airmass over central/se IL with
SB CAPES 2500-3500 j/kg south of I-74 while MLCapes were 1-2k j/kg.
PW values were 1.5-1.9 inches from Shelbyville to Paris south
where deeper tropical moisture was. More widespread convection was
over southern IN into western half of KY/TN and sw of St Louis
metro over central and south central MO into north central AR.
Very warm and humid conditions prevailed over CWA with temps
86-92F and heat indices in the 90s, with SPI, DEC, LWV and HUF
reaching 99 heat index.

Isolated convection will linger south of I-72 until sunset, though
severe storms not expected. Patchy fog is possible again later
tonight and early Sunday morning south of I-72. Muggy lows in the
lower 70s overnight across the CWA.

Isolated to scattered convection to redevelop over central IL on
Sunday from sw to ne in tropical airmass. Very warm and humid
again on Sunday with highs in the upper 80s to around 90F (warmest
I-74 north) and heat indices peaking in the mid to upper 90s. Better
coverage of convection will be during Sunday night into Monday as
cold front moves in during Monday. SPC Day2 outlook has marginal
risk of severe storms Sunday night for damaging winds over the IL
river valley in nw CWA, with slight risk over much of Iowa and
north central and nw MO. SPC Day3 has marginal risk of severe
storms for damaging winds from the IL river se on Monday as cold
front moves through. Highs Monday in the mid 80s central IL and
upper 80s in southeast IL with heat indices 90-95F. Chance of
showers and thunderstorms lingers se of I-55 Monday evening and
goes longer in the evening Monday over southeast IL.

Weak high pressure drifts into the area Tue night and Wed bringing
dry conditions with more seasonable temperatures and humidity
levels. Highs in the mid to upper 80s Tue and Wed but dewpoints
lowering from 70s Monday to 60s Tue and Wed.

Upper level ridge building back over the Eastern Plains and MS
river valley late next week to bring back some more heat and
humidity, though not quite as hot as this past week. Have isolated
convection chances Thu and Fri afternoon with 20-40% chance of
showers and thunderstorms next Saturday. Highs in the upper 80s to
near 90F Thu, around 90 Fri and lower 90s next Saturday as heat
indices climb back into the mid 90s to near 100F next Fri/Sat.

07

&&

.AVIATION...  (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1255 PM CDT Sat Jun 28 2025

A boundary was south of I-72 at early afternoon extending along a
Taylorville to Lovington to Charleston to Chrisman line and has a
few convective cells recently developing along it in NE Shelby
and western Moultrie counties. This boundary and more unstable
air mass to slowly sag southward this afternoon and evening,
keeping convection chances mainly south of I-72 but will be close
to SPI and DEC airports next few hours. Scattered to broken
cumulus clouds this afternoon with bases 2.5-3.5k ft early this
afternoon to slowly lift into VFR category during mid/late
afternoon. More isolated convection to return into sw IL Sunday
morning, but should stay sw of central IL airports until after
18Z/1 pm Sunday. South to SE winds near 5 kts this afternoon to be
light and variable tonight and be south at 5 kts after 15Z/10 am
Sunday.


07

&&

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

$$