582
FXUS63 KPAH 131100
AFDPAH

Area Forecast Discussion
National Weather Service Paducah KY
600 AM CDT Sun Sep 13 2026

.KEY MESSAGES...

- Very warm conditions with small rain chances in parts of
  southeast Missouri and north of Interstate 64 are forecast
  today and Monday.

- A major late season heat wave is forecast Tuesday through
  Thursday. High temperatures will reach the middle to upper 90s
  with daily peak heat index values around 105 degrees or
  higher. A Heat Advisory will very likely be needed.

- Slightly cooler and less humid conditions arrive by the end of
  the week, along with low-end 15 to 25% chances of
  thunderstorms Friday and Saturday.

&&

.UPDATE...
Issued at 559 AM CDT Sun Sep 13 2026

Updated Aviation discussion for the 12z TAF issuance.

&&

.DISCUSSION...
Issued at 1255 AM CDT Sun Sep 13 2026

The main story over the next several days will be a major late
season heat wave, with the worst of the heat being Tuesday
through Thursday. The driver of this heat will be a very strong
H5 ridge that will expand from the southern Plains into the
Mid-South by Tuesday.

Until then, very warm temperatures and elevated humidity levels
by mid-September standards are forecast today and Monday. High
temperatures will reach the lower to middle 90s and upper 80s to
lower 90s today and Monday, respectively. Heat index values
south of I-64 will be around 100 degrees. While just shy of Heat
Advisory criteria, given the late season nature of the
conditions, did issue a Special Weather Statement through 23z
for areas south of I-64 highlighting the elevated heat
conditions.

A frontal boundary just the northwest will attempt to move into
the area today into Monday. This front may kick off a few stray
showers or thunderstorms (15-25%) in northern parts of southeast
MO and locations north of I-64 today and tomorrow. Overall, the
great majority of the region will stay dry, and locations that
do see rain will see 0.10" or less on average.

As mentioned earlier, the worst of the heat looks to be Tuesday
through Thursday. The intensity of the upper-level ridging is
very anomalous for mid-September. Ensemble guidance shows a
596-599dm ridge (95-99th percentile) centered over the Mid-
South during this time. Temperatures at 850 mb will range from
19-22C which is also in the 95-99th percentiles. Actual air
temperatures will reach the middle to upper 90s (around record
levels). With dew point temperatures in the lower to middle
70s, peak heat index values around 103-108F are expected. A Heat
Advisory will very likely be needed for most of all of the
forecast area.

Beyond Thursday, ensemble guidance has trended slower from
previous forecasts in breaking down the ridging over the region.
This means high temperatures will still be in the lower 90s on
Friday and the upper 80s to lower 90s Saturday. However, it
appears dew point temperatures will draw down into the 60s,
which will keep heat index values in the 90s. A frontal boundary
will also move towards the area from the northwest, which will
also kick off a few showers and storms during the heat of the
day Friday and Saturday.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 559 AM CDT Sun Sep 13 2026

Patchy shallow fog around CGI and PAH will mix away by 13z.
Otherwise, VFR conditions are expected with FEW diurnal CU
development expected under robust cirrus cloud cover. Winds will
be light from the NW through this afternoon around 4-6 kts
becoming N to NNE.

&&

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

&&

$$

UPDATE...DWS
DISCUSSION...DWS
AVIATION...DWS