246
FXUS63 KPAH 231710
AFDPAH

Area Forecast Discussion
National Weather Service Paducah KY
1110 AM CST Mon Dec 23 2024

.KEY MESSAGES...

- Warmer temperatures are expected today above normal
  temperatures are expected through the weekend.

- Chances for mainly light rain arrive tonight and will linger
  through Christmas Eve and Christmas Day.

- After a brief break in the rain Thursday, another round of
  rain and a few thunderstorms are forecast Friday and Saturday.
  Some of these storms could produce locally heavy rain.

&&

.UPDATE...
Issued at 1109 AM CST Mon Dec 23 2024

Updated Aviation discussion for the 18z TAF issuance.

&&

.DISCUSSION...
Issued at 1254 AM CST Mon Dec 23 2024

Surface winds have shifted around to the southeast and
temperatures have responded by stopping their steady fall
overnight. A warm front, focused more strongly aloft with low
level warm advection to the south, will form up this afternoon
and serve as a lift mechanism for light rain showers that will
become a little more numerous as the evening and overnight
progresses. Stronger large scale ascent associated with a sharp
shortwave trough on slow approach from the Plains largely looks
to stay to the west of the region until the overnight hours
Christmas morning. Layer warm advection and small spokes ahead
of the parent shortwave will still provide some lift for areas
of rain through the day Tuesday/Christmas Eve. High temperatures
will rise close to 50 today and be slightly warmer Tuesday and
Wednesday.

This first shortwave starts to get nudged and modified by a
stronger/sharper trough and embedded closed low by Christmas
Day. The trend in guidance has been for less coverage/QPF ahead
of the trough as it weakens under the influence of the
approaching trough from the west. There will still be at least
some rain around however with light precip remaining in the
forecast through Thursday morning.

At this point details become much more challenging. The overall
theme in guidance is this second shortwave then swings negative
moves to the northwest and is replaced by a pair of shortwaves.
The ECMWF and GFS differ greatly on whether the trough
consolidates and moves through definitively on Saturday (ECMWF)
or hangs back until Sunday (GFS). The ensemble members are in
fairly similar camps to their parent deterministic model. This
jet-level pattern is complicated and a little bit unusual so its
fair to expect higher uncertainty than usual at this range.

As far as impacts go the trough positions still look a little
too far southeast to be a prime severe weather threat for us.
Heavy rain potential would still be there if things came
together right although the rapid fire progression of the
troughs means the surface and deep layer moisture return
between each trough is limited. Although the semi-permanence of
precip/lift for Thursday-Saturday or Sunday does bear continued
vigilance for flooding rain.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1109 AM CST Mon Dec 23 2024

Mid-cloud bases around 5-8kft will lower tonight as the low
levels of the atmosphere gradually saturate. The abundant dry
air will limit any precipitation to mainly just sprinkles or
very light rain through Tuesday morning. Afterwards there will
be relatively low rain chances for the last six hours of the
forecast period. Cigs will gradually lower to MVFR, with some
vsby reductions possible as well with the arrival of the rain.

Winds will be gusty from the S around 8-12 kts with gusts to
18-22 kts through this afternoon, then relaxing tonight and
eventually becoming light and variable.

&&

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

&&

$$

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