150
FXUS63 KILX 062256
AFDILX

Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
556 PM CDT Sun Jul 6 2025

.KEY MESSAGES...

- Expect scattered showers and thunderstorms today, with lingering
  chances in southeast IL on Monday. Locally heavy rainfall,
  lightning and a few strong wind gusts are possible this
  afternoon into mid evening mainly east of I-55.

- Seasonably hot and humid conditions are expected the next
  several days, with highs mainly from the mid 80s to around 90,
  and heat index peaking around 90 to 95 daily.

- Occasional periods of scattered showers and thunderstorms can be
  expected for the upcoming work week.

&&

.DISCUSSION...
Issued at 222 PM CDT Sun Jul 6 2025

Lift associated with an upper level shortwave trough and a cold
front draped northeast to southwest across central IL have
prompted the initiation of scattered showers and thunderstorms
this afternoon, which should continue into this evening before
diminishing over the area overnight as the front pushes to the
south and the shortwave moves to the east. With MLCAPE values of
2000-3000 J/kg but weak shear, a few strong storms containing
strong wind gusts could take place, and a SPC has designated a
Marginal Risk for severe storms. HREF ensembles continue to
advertise very isolated 2-3 inch rainfall accumulations through
this evening due to slow storm motion and precipitable water near
2 inches. Isolated instances of flash flooding will need to be
watched for, especially if occurring in urban or poor drainage
areas.

With the front lingering just south of the I-70 corridor Monday, we
could see another round of showers and thunderstorms near and south
of I-70, then a break should take place Monday night as surface high
pressure drifts by to the north, ridging into central IL.

A few upper level waves in a weak zonal/westerly flow pattern look
to bring chances for more showers and thunderstorms midweek through
next weekend. Although timing is far from certain at this point, the
first of these looks to work its way slowly across the area late
Tuesday through Wednesday, followed by a couple more late week
into the weekend. PoPs Wednesday through the weekend depict
somewhat of a diurnal trend with highest values during the
afternoon to early evening, generally 30 to 50 percent. Severe
weather chances look to be generally low, although a few model
runs depict a potent enough shortwave for severe weather around
Friday.

Temperatures look to run seasonably hot and humid for the upcoming
week, with highs ranging from mid 80s to around 90, lows from mid
60s to lower 70s, and dewpoints from the 60s to lower 70s, resulting
in heat index values peaking around 90 to 95 daily.

37

&&

.AVIATION...  (For the 00z TAFs through 00z Monday Evening)
Issued at 556 PM CDT Sun Jul 6 2025

A cold front is pushing into central IL this evening. Isolated
TSRA are possible across the local terminals through 02z or so,
with KSPI-KDEC-KCMI in the better location to see any storms.
After that concern is for MVFR ceilings to develop behind the
front after 06z. Guidance continues to point towards KDEC-KCMI
most likely to see these ceilings, but will need to watch trends
later this evening if this can build back far enough west to
affect KBMI-KSPI. The lower ceilings should rise above MVFR mid to
late morning with VFR prevailing thereafter. Winds to be light
under 10 kt through the forecast, veering north behind the frontal
passage.

25

&&

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

$$