686
FXUS63 KILX 071055
AFDILX

Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
555 AM CDT Sat Jun 7 2025

.KEY MESSAGES...

- SPC removed the severe weather risk for today across central and
  southeastern IL. Showers and thunderstorms are expected today,
  with localized heavy rainfall (especially south of I-70).

- Sunday has a marginal risk for the entire CWA with areas west of
  the I-155/I-55 corridor in a slight risk. SPC indicates as the
  storms move further east of the Mississippi River, they will
  lose their severe ability.

- A dry stretch of weather shows its face starting late Monday
  morning into Thursday as a high pressure system settles over the
  Ohio Valley.

&&

.DISCUSSION...
Issued at 232 AM CDT Sat Jun 7 2025

This morning is shaping up to be a foggy one for areas near and
south of the I-72 corridor. There is a Dense Fog Advisory out for
the southern half of the CWA this morning, expiring by 14z (9am) as
the sun erodes the fog. We could see some more fog tomorrow morning
as well with the moist grounds and light winds. How dense it gets
will depend on if there are any areas of sky clearing overnight
tonight. Highs today in the mid 70s.

More showers and thunderstorms are forecast to move through central
IL this afternoon, associated with a weak low pressure system. The
low center will progress eastward across southern / southeastern IL.
The SPC has removed the entirety of the CWA out of the marginal risk
for severe weather for today. The thunderstorms this afternoon into
evening should behave themselves. South of I-70 there is around 1000
J/kg of CAPE, little to no CIN, and ~20 knots of bulk shear. The
soundings have the appearance of a heavy rain event, more than a
severe shape. There are values of 1.6-1.8 of PWAT, long skinny CAPE
profile, and slow storm motions (15-30 knots). localized 1 inch
amounts or more are likely in stronger cells. They should exit just
after midnight tonight.

Tomorrow we have even more chances for showers and thunderstorms.
The difference being more of a severe risk with these storms, with
all hazards possible. This round is firing along a cold front that
will move through the CWA from late tomorrow afternoon into Monday
morning. SPC has us in a marginal risk for the entire CWA with
areas west of the I-155/I-55 corridor in a slight risk. SPC
indicates as the storms move further east of the Mississippi
River, they will lose their severe ability.

From Monday morning to early Thursday, a high pressure system
settles into the Ohio Valley. We finally see a period of drier
weather during this period. Temperatures will warm into the 80s
for highs by Wednesday and should stay there into the weekend.
Lows will warm into the mid to upper 60s.

The dry weather won`t stick around long. By Thursday afternoon, more
rain chances enter the forecast again into next weekend as a
disturbance or two traverse the region.

Copple

&&

.AVIATION...  (For the 12z TAFs through 12z Sunday Morning)
Issued at 555 AM CDT Sat Jun 7 2025

MVFR visibilities are in place over CMI/DEC and IFR vis at SPI
this morning associated with patchy dense fog. At times, SPI
will have LIFR vis & ceilings before the fog erodes with the
daylight.

Light winds will hangs around for much of the period, though some
stronger wind gusts are possible in any heavier showers or
thunderstorms this afternoon (along with some MVFR visibilities).
A system will push through bringing showers and thunderstorms to
the forecast sites after 20z this afternoon, moving east, exiting
CMI near 06z tonight. Behind the system, ceilings will lower to
MVFR overnight, then scattering out tomorrow morning.

Copple

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory until 9 AM CDT this morning for ILZ042>044-
047>057-061>063-066>068-071>073.

&&

$$