524
FXUS63 KILX 121754
AFDILX

Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
1254 PM CDT Sat Jul 12 2025

.KEY MESSAGES...

- Thunderstorms will move across southeastern IL this afternoon.
  Areas of heavy rainfall are the main threat for isolated
  flooding, especially if it falls in urban and poor drainage
  areas. SPC has a marginal risk of damaging winds as well.

- Hot and humid conditions will be in place again today and again
  early next week. Temperatures look to trend slightly cooler by
  the end of next week.

&&

.DISCUSSION...
Issued at 210 AM CDT Sat Jul 12 2025

The trailing stratiform rain region is slowly deteriorating this
morning. It has mostly hung along and west of the I-55 corridor. The
barely existant line of showers is now moving east of the I-57
corridor. Not much convection is left and lightning has been
limited. As this erodes this morning, drier weather over much of
central IL is expected today.

There is a marginal risk of severe weather that expands south-
southeast of a Danville to Vandalia line. HRRR shows storms
developing along I-57 and moving east, whereas the NAMNest is
slightly further south showing a complex of storms developing south
of I-72 this afternoon. These storms are forecast to develop around
20z (3pm). They hold the potential for damaging winds up to 60 mph.
We could see some heavy rain south of I-70, where PWATs are around 2
inches.

After those storms move out, a cold front will sweep through the CWA
this evening. Some of the CAMs are showing some showers or
thundershowers developing along the front after 00z. They could drop
up to an inch of rain locally for some lucky few. PWATs aren`t
nearly as high as they have been, but they are still around 1.6-1.8
inches.

Behind the cold front, much less humid air moves in, but not much
cooler temperatures. Today the highs are in the mid 80s to low 90s,
and that will be the general theme into the new week. The hottest
day of the week looks to be Wednesday, with highs around 90 and heat
indices of 95-105 degrees.

The next best chance for rain and storms come Tuesday with a 40-50%
chance and Wednesday with a 60-70% chance. A lot like last week,
most days have a non-zero chance for showers and thunderstorms, but
nothing looks to be organized, just messy convection. It is mid-July
after all.

Copple

&&

.AVIATION...  (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1254 PM CDT Sat Jul 12 2025

Low stratus has led to MVFR ceilings over a good portion of the
state to start the day. A cold front positioned just west of the
Illinois River is in the process of pushing east, with stratus
thinning out behind it. Scattered showers and storms out ahead of
the front will lift northeast over eastern Illinois this afternoon,
likely only impacting KCMI (30% chance). Primary hazards would be
strong wind gusts and visibility reduced from heavy rainfall. Storms
so far today have had wind gusts of 30-40 mph.

Southwest winds will shift to the northwest behind the front tonight
with speeds remaining below 10 kts. Winds become light and variable
going into Sunday morning, then take on a westerly direction by late
morning or afternoon.

NMA

&&

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

$$