844
FXUS63 KILX 031044
AFDILX

Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
544 AM CDT Mon Jun 3 2024

.KEY MESSAGES...

- Showers and thunderstorms this afternoon (50-60% chance) for
  areas west of I-57. There is a threat for isolated strong to
  severe storms this afternoon (hail and stronger winds).

- More storms and showers late tomorrow afternoon into the
  overnight hours ahead of a passing cold front. There is another
  threat for strong-to-severe storms late tomorrow.

- A drier pattern sets up for the end of the week.

&&

.DISCUSSION...
Issued at 300 AM CDT Mon Jun 3 2024

Some patchy fog is occuring across central Illinois this morning..
Dewpoint depressions are 0 for many locations which is mixed with
clear skies and light winds. The morning sun will erode the areas
experiencing fog this morning. A shortwave is expected to move
through central Illinois today, bringing isolated strong to severe
thunderstorms and some showers. There is a MCV trekking across the
middle Mississippi Valley that could influence how long-lived the
storms are.

There is more than sufficient instability (1500-3000 J/kg SBCAPE) to
support thunderstorms this afternoon. The bulk shear values,
however, are nonexistent (10-15kts) with unimpressive mid-level
lapse rates (~6.5 C/km). The storms that do develop will be short-
lived and pulsey without the shear to keep them alive, unless the
passing MCV can locally increase the wind shear. They could be
capable of marginally severe hail and stronger wind gusts as they
collapse (DCAPE values near 1000 J/kg). The 06z HRRR and 00z NAMNest
is showing the main area of interest being west of I-57.

Tuesday will look quite similar to this afternoon in terms of pop up
type thunderstorms, except there is weaker instability in the
afternoon (1000-1500 J/kg SBCAPE). The 06z HRRR is showing the
development of the afternoon storms/showers being east of the
Illinois River valley. The main threat for severe weather looks to
come late evening into the overnight hours tomorrow ahead of the
cold frontal passage on Wednesday. However, we are not expecting it
to be widespread.

For the remainder of the week, a drier pattern sets up for a few
days. There is a small chance (10-25%) of any rain over the weekend.
Highs will hang around the upper 70s to low 80s through Sunday.

Copple

&&

.AVIATION...  (For the 12z TAFs through 12z Tuesday Morning)
Issued at 544 AM CDT Mon Jun 3 2024

There is some fog in central Illinois this morning, affecting
BMI/DEC/CMI. Once the fog erodes (after 14z), today will be a VFR
kind of day. There is a 20-40% chance of showers and thunderstorms
this afternoon (after 18z), but the location of where they will pop
up is uncertain. I have chosen to leave out mention of SHRA/VCSH or
any TS due to the uncertainty for this TAF cycle.

Copple

&&

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

$$