842
FXUS63 KPAH 190436
AFDPAH

Area Forecast Discussion
National Weather Service Paducah KY
1136 PM CDT Wed Jun 18 2025

.KEY MESSAGES...

- Severe thunderstorms remain possible late this afternoon into
  this evening mainly over west Kentucky . Damaging wind gusts
  will be the main threat, with small risks of large hail or a
  brief tornado.

- A Lake Wind Advisory remains in effect for most of the region
  through 7 PM CDT.

- Dangerous, prolonged heat and humidity arrive Saturday and
  will continue through at least Tuesday. Daily peak heat index
  values of 100 to 105 degrees are forecast with only limited
  relief at night.

&&

.DISCUSSION...
Issued at 339 PM CDT Wed Jun 18 2025

Ongoing storms in southwest Indiana have strong cores, but are
not well organized, while convection farther south through west
Kentucky are also struggling to intensify. SPC mesoanalysis
shows 2500-3000J/kg MLCAPE available over most of the region,
but Effective Bulk Shear is only 25-30kts in Indiana and less
than that in Kentucky. Despite the strong instability, mid-level
lapse rates are unimpressive. However, low-level lapse rates
are quite steep and downdraft CAPE is near 1000J/kg, so would
expect to see storms continue to produce strong downburst winds
from time to time late this afternoon. The convection should be
out of southwest Indiana by 5 PM, while it will likely hang on
through 01Z or so in west Kentucky.

The latest HRRR develops new convection around 22Z near Hickman
Kentucky and pushes it rapidly eastward across west Kentucky
with some evidence of upscale growth and a more widespread
damaging wind concern before it exits to the east around 01Z.
Perhaps the shear improves a bit toward this evening, but given
the way the models have handled this event, confidence is quite
low.

Scattered convection could redevelop back to the west and move
across the Quad State later this evening through the overnight
hours. This activity should be elevated and instability should
be very limited, so would mainly be looking at a lightning and
locally heavy rainfall threat tonight.

The Lake Wind Advisory still looks good through sunset, so will
let it go to expiration at 00Z.

After a brief cool, dry intrusion over the region Thursday, real
summertime heat and humidity will develop Friday through next
Wednesday. Temperatures will climb to around 90 on Friday, and
then into the lower 90s throughout the area Saturday. South
winds will bring back lower 70 dewpoints Saturday which will
take heat index values into the triple digits.

The upper ridge will build over the Ohio Valley this weekend
and then weaken next week. Heat indices will likely hold in the
100-105 range from Saturday through at least Tuesday, which does
bring up the possibility of hitting the 4-day Heat Advisory
criteria Tuesday and possibly Wednesday. Also as the ridge
weakens, there will be some chance of diurnal convection Tuesday
and Wednesday. Of course, that would muddy the potential Heat
headline potential.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1133 PM CDT Wed Jun 18 2025

Areas of showers and a few embedded thunderstorms will continue
to move eastward overnight. Its possible some of this activity
may impact the southern terminals but confidence is low. MVFR
cigs are more likely at EVV/OWB between 12-15Z. Conditions will
dry out this morning with clearing skies by the afternoon.
Southwest winds around 5 knots expected this morning increasing
to between 5 and 10 knots this afternoon.

&&

.PAH WATCHES/WARNINGS/ADVISORIES...
IL...None.
MO...None.
IN...None.
KY...None.

&&

$$

DISCUSSION...DRS
AVIATION...AD