639
FXUS63 KPAH 080621
AFDPAH

Area Forecast Discussion
National Weather Service Paducah KY
121 AM CDT Mon Jun 8 2026

.KEY MESSAGES...

- Batches of thunderstorms producing heavy rain and some risk
  for severe weather (tornado/wind) are expected in waves today.
  The risk for heavy rainfall and flash flooding is increasing
  and a flash flood watch has been issued for parts of the
  area.

- The hottest stretch of the season begins on Tuesday with high
  temperatures nearing 90 degrees. A combination of the heat and
  humidity will cause daily heat index values to rise around 100
  degrees through Thursday, followed by some relief on Friday.

- Another front approaches late Thursday or Friday and may
  produce another heavy rain and muted severe weather risk.

&&

.DISCUSSION...
Issued at 120 AM CDT Mon Jun 8 2026

The overall synoptic picture is messy and unsettled and the
forecast is similar. There is a sharp upper level low digging
into southwest Missouri and a sharply diffluent zone to its east
moving into our northwestern counties right now. Underneath
that disturbance lies just pure soup with dewpoints at the
surface 70 to 75 degrees with more advecting in from the
southwest all the time. New convection is initiating in
southwest Missouri behind the upper low where 3-6 km lapse rates
presumably have steepened a little. There is a narrow area of
reasonably favorable deep and low layer shear for isolated
supercell type activity over our northwestern zones this morning
and if that area of diffluence can help initiate surface based
convection a brief severe weather/tornado threat may emerge
before sunrise.

As the day wears on the upper low moves slowly eastward. The
actual low gets overhead but residual diffluence below 300mb and
the soupy airmass looks sufficient to initiate thunderstorms
through the day with the best coverage likely over the eastern
half of the area. As that is occurring the larger scale pattern
starts to feel broader troughing over the Rockies keeping a
moist conveyor belt going through the late afternoon and
evening. A weak front aloft looks to act as a foci for showers
and storms. Given the 2.1 to 2.3 inch PWATs indicated and the
large warm cloud layer depth rainfall would be able to be
extremely efficient. Each of the last few evenings as this low
has rumbled around the area to our west and southwest it has
sparked a few supercells and persistent heavy rainfall. I think
we will have to be on guard for that to happen once again today.
The best risk for any severe will along and just ahead of the
upper low which looks to time out over roughly the eastern half
of the CWA where a few damaging wind and isolated tornadoes
appear possible.

HREF PMMs have steadily been trending upward on precip amounts
in the eastern half of the CWA with some 3 to 4 inch swaths.
This coupled with the overall picture suggests enough potential
for flash flooding that will hoist a watch for parts of the
area.

PoP trends are up a little on Tuesday morning as modest mid
level height falls impact the area. MLCAPEs 2500-3000 J/kg with
fairly weak deep shear, suggestive of at least some pulse severe
threat. The highest heat levels of the year so far follow with
heat index values around 100 each day through Thursday.

A shortwave trough pushes a cold front towards the area Thursday
night into Friday. This looks like another potential heavy rain
and modest severe weather threat. A cold front clears but almost
immediately returns as a warm front into the weekend with
another fairly strong shortwave on track for late Sunday for
now.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1114 PM CDT Sun Jun 7 2026

MVFR cigs for the most part anticipated overnight as a slow
moving storm system impacts the area. Convection in a few waves
will also remain a factor through much of the period. Broad
prob30s highlight both the uncertainty of timing in the very
soupy airmass and the potential for more than one round of
operationally significant TSRA.

&&

.PAH WATCHES/WARNINGS/ADVISORIES...
IL...Flood Watch from this afternoon through Tuesday morning for
     ILZ076>078-082-083-086-087-090-091.
MO...None.
IN...Flood Watch from this afternoon through Tuesday morning for
     INZ081-082-085>088.
KY...Flood Watch from this afternoon through Tuesday morning for
     KYZ007-010>022.

&&

$$

DISCUSSION...JGG
AVIATION...JGG