275
FXUS63 KPAH 131842
AFDPAH

Area Forecast Discussion
National Weather Service Paducah KY
142 PM CDT Mon May 13 2024

.KEY MESSAGES...

- Shower and thunderstorm chances will peak later tonight into
  Tuesday. A stronger storm cannot be ruled out, but the risk
  remains very marginal.

- While rain chances on Wednesday will be much lower, another
  risk for showers and thunderstorms returns Thursday afternoon
  into Friday. Rain chances may linger through Sunday, but the
  weekend overall does not appear to be a washout.

- Temperatures will be near normal through the middle of the
  week before gradually rising above normal late week into the
  weekend.

&&

.DISCUSSION...
Issued at 140 PM CDT Mon May 13 2024

The synoptic setup this week is quite unsettled as a 500 mb
shortwave trough and low ejects across the Plains today, providing
forcing for ascent. Scattered showers and a few isolated
thunderstorms will be possible through this evening, with the better
risk for convection arriving late tonight into early Tuesday
morning. The RAP shows about 600-850 J/kg of 0-1km MLCAPE with
pockets of bulk shear upwards 30-35 kts and 700-500 mb lapse rates
around 6.5 C/km, keeping the severe risk very marginal mainly across
southeast Missouri. Although the 0-1km MLCAPE will be upwards of
1000-1500 J/kg Tuesday afternoon when another uptick in pcpn is
progged, the shear will be decreasing. Overall, the setup is very
marginal, but a stronger storm cannot be ruled out, with the risk
shifting east into western Kentucky on Tuesday. QPF generally
remains between a half to one inch for most of the FA, with locally
higher amounts possible.

By Wednesday, the FA will still be under the influence of cyclonic
flow on the backside of the aformentioned 500 mb low as recent runs
of the GEFS/EPS and deterministic ECMWF are more pessimistic.
Meanwhile, the 12z GFS/NAM remain more progressive keeping most of
the FA dry. Given that the overall trend favors a slower departure,
NBMs 20-40% PoPs seem reasonable for Wednesday, especially across
southwest Indiana and western Kentucky where the risk of seeing pcpn
will be the greatest. Locations near and west of the Mississippi not
only likely remain dry, but can also expect breaks of sun as a weak
ridge axis aloft eventually moves over the entire FA Wednesday night.

While Thursday looks to start off dry, southern stream energy will
eventually eject NE towards the FA bringing the risk for more
showers and thunderstorms Thursday afternoon into Friday.
Uncertainty then increases over the weekend as model ensembles are
not in agreement on if the southern stream energy gets held back
with NBM chance PoPs progged for both days. Despite the lower
forecast confidence, the entire weekend does not appear to be a
washout. It is also possible most of the weekend remains dry if the
12z ECMWF/CMC were to be correct while the GFS lingers pcpn into
Saturday.

Temperatures will be near normal Tuesday and Wednesday with maxTs in
the mid to upper 70s and minTs in the upper 50s to lower 60s.
Daytime temps gradually warmer into the low 80s Thursday and Friday
before eventually rising into the mid 80s over the weekend with
nighttime temps in the low to mid 60s.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1213 PM CDT Mon May 13 2024

The main concern is MVFR/IFR cigs building in from the west
through this evening as a disturbance approaches. A few
scattered showers will also be possible, perhaps a rumble of
thunder. A greater risk for showers and storms arrive during the
overnight when TSRA cannot be ruled out, especially at
KCGI/KPAH. Brief MVFR vsbys are also possible early Tuesday
morning as low cigs prevail across the entire region. Light S-SE
winds between 5-11 kts are expected.

&&

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

&&

$$

DISCUSSION...DW
AVIATION...DW