530
FXUS63 KPAH 192259
AFDPAH

Area Forecast Discussion
National Weather Service Paducah KY
559 PM CDT Fri Sep 19 2025

.KEY MESSAGES...

-Above normal temperatures to start off the weekend turn more
 seasonable by early next week, trending below normal in the
 latter half of the week.

-Daily rain chances will begin to increase in coverage Sunday
 into Monday, with heavy rainfall more probable through the
 middle of the week. Total rainfall between 1 to 3 inches is
 possible by next Thursday.

&&

.UPDATE...
Issued at 559 PM CDT Fri Sep 19 2025

Updated Discussion for the 00z TAF issuance.

&&

.DISCUSSION...
Issued at 207 PM CDT Fri Sep 19 2025

PVA associated with a shortwave trough over the the central Plains
will provide subtle lift for an axis of isolated showers and storms
this afternoon and evening. Although storms will remain very
localized, heavy downpours, lightning, and brief gusty winds will be
the main concern due to steep low-level lapse rates of 8.0 to
9.0 C/km and MLCAPE between 500 to 1500 J/kg. Pcpn chances turn
even more sporadic on Saturday before increasing Sunday into
Monday due to an influx of moisture transport from the
southwest.

As a 500 mb cutoff low develops by the middle of the week near
the Ohio Valley, a weak sfc low pressure will develop in the
vicinity of the FA, pulling in even more moisture from the Gulf.
The synoptic setup will set the stage for much needed rainfall
between Sunday and Thursday. The 12z GEFS and EPS are in much
better agreement, supporting at least 1 to 2 inches of total
rainfall by the latter half of the week. In fact, both model
ensembles now support a 70 to 90% probability of exceeding 1
inch of rainfall and 40 to 60% for exceeding 2 inches. The
deterministic ECMWF and CMC remain the most robust with locally
3 to 4 inches, while the GFS continues to trend towards the
wetter scenario.

Due to the long duration, any flooding issues should remain confined
to vulnerable low-lying and poor drainage locations. While the
overall flood risk is marginal, the risk for runoff on roadways
will be greater given the hard soil conditions combined with
PWATs between 1.50 to 1.75 inches. As the aformentioned closed
low slowly pushes east Thursday into Friday, heavy rainfall
will begin to taper, but lingering showers still are progged by
the NBM due to persistent cyclonic flow on the backside.

Overall, increasing confidence in a wetter pattern next week will
yield more cloud cover that will support a significant cool down.
Temperatures that will be about 5 degrees above normal to start
off the weekend in the mid 80s to near 90 trend more seasonable
into the low 80s by early next week. In fact, temperatures 5
degrees below normal are now progged by the NBM in the upper 70s
next Thursday as the 500 mb cutoff low causes 850 mb temps to cool
down to near 10C.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 559 PM CDT Fri Sep 19 2025

For the 00z TAF issuance, isolated to scattered showers and
thunderstorms will continue through about 01-03z for diminishing
overnight. The greatest coverage will be across southeast
Missouri, with lesser coverage over southern Illinois and
western Kentucky. In areas that saw rain earlier today,
particularly in southeast Missouri, fog development may become
an issue around daybreak. Have included TEMPO MVFR fog groups at
CGI and PAH, but if confidence in fog impacts increases, lower
restrictions may be needed with the next forecast package. Light
and variable winds overnight will increase from the S-SW after
15-18z, around 4-8 kts.

&&

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

&&

$$

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