638
FXUS63 KPAH 201720
AFDPAH

Area Forecast Discussion
National Weather Service Paducah KY
1220 PM CDT Fri Sep 20 2024

.KEY MESSAGES...

- Conditions will remain unseasonably warm and humid through
  Monday with highs ranging from the upper 80s to lower 90s.

- A weak disturbance may trigger a few isolated light rain
  showers this morning and tonight across portions of the
  region, but more widespread shower and thunderstorm activity
  holds off until Sunday into Monday as a cold front approaches.

- Much cooler conditions return for the middle of next week
  behind a cold front along with lingering rain chances.

&&

.UPDATE...
Issued at 1219 PM CDT Fri Sep 20 2024

Updated Aviation discussion for the 18z TAF issuance.

&&

.DISCUSSION...
Issued at 203 AM CDT Fri Sep 20 2024

More humid conditions are in store to end the week as sfc high
pressure located over the deep south moves east allowing for
southwesterly return flow. Dewpoints are progged to rise into the
upper 60s to lower 70s, making it feel a lot more like summer.
Unseasonably warm conditions remain in place through the
weekend as 850 mb temps rise above the 95th percentile to near
20C. This translates to maxTs around 90 and minTs in the upper
60s to near 70. Otherwise, modest isentropic lift and WAA at 850
mb will support a chance of a few isolated light rain showers
this morning in southern Illinois and southeast Missouri, with
a returning slight chance tonight mainly north along I-64.
Although the rain chances are non-zero, most of the FA likely
remains dry through Saturday with rising heights aloft.

Amplification in the synoptic flow will lead to more unsettled
weather on Sunday as a 500 mb shortwave ejects across the central
Plains. Forcing for ascent due to multiple leading impulses will
support more widespread shower and storm chances into Monday. Model
guidance shows a cold front eventually moving through Monday night
into Tuesday as a deep longwave 500 mb trough digs across the
central CONUS. The general consensus is for 0.50 to 1.00 inches
of total QPF with locally higher amounts possible due to
convection.

Behind the cold front on Tuesday, slightly below normal temps
are in store through the middle of the week due to troughing
aloft. MaxTs are progged by the NBM to only be around 80 with
minTs falling into the 50s. Forecast uncertainty still remains
quite high for the end of the week as model ensembles show a
large spread in the evolution of a potential tropical
disturbance down in the Gulf of Mexico.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1219 PM CDT Fri Sep 20 2024

For the 18z TAFs, steady SW surface flow will continue ahead of
the approach of a weak cold front. Winds will be 5-10 kts this
afternoon, relaxing to 5 kts or less overnight. This front may
kick off some isolated convection this evening, but coverage at
this time looks to be too low to mention in any TAF at this
time. FEW-BKN diurnal CU with bases around 7kft will wane this
evening, with SCT mid- and high-level cloud cover persisting
through the remainder of the period.

&&

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

&&

$$

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