442
FXUS63 KPAH 131117
AFDPAH

Area Forecast Discussion
National Weather Service Paducah KY
617 AM CDT Mon May 13 2024

.KEY MESSAGES...

- Showers and thunderstorms return to the region today with
  chances peaking tonight into Tuesday. Can`t rule out a strong
  storm, but chances are quite low.

- After a brief break mid-week, rain chances return Thursday
  afternoon through Friday.

- Temperatures will be near to slightly below normal early in
  the week and then nudge up to a bit above normal later in the
  week into the weekend.

&&

.UPDATE...
Issued at 608 AM CDT Mon May 13 2024

Updated aviation discussion for 12z TAFs.

&&

.DISCUSSION...
Issued at 242 AM CDT Mon May 13 2024

A mid-level shortwave and upper low will progress eastward from the
Plains today and become centered over the Mid Mississippi Valley on
Tuesday. Guidance is suggesting MCS activity down in AL/MS this
morning may hamper northward moisture return into our region. This
may lead to more isolated to widely scattered showers today, with
possibly a few thunderstorms. Think the better chance for more
robust convection may hold off until this evening or overnight as
the upper low drifts closer. Then a secondary flare up during the
day on Tuesday when we see higher instability.

Overall, the severe threat looks very marginal with this system, but
it can`t be completely ruled out. MUCAPE looks to remain well below
1000 j/kg through tonight, but shear of 35-40 kts looks to be
present especially this evening and overnight. Meanwhile, higher
instability of 1000-1500 j/kg is anticipated on Tuesday, but with
the best shear departing to our southeast leaving behind 20-25 kts
at best. Tend to think the best chance late this afternoon and
evening would be across southeast Missouri and then shift to western
Kentucky on Tuesday afternoon. Very marginal setup though.

Little change with the QPF forecast, still likely running in the
0.5" to 1" for most locations. Likely will be some localized higher
amounts upwards of 1.5". Given the splotchy nature there`s also a
good chance some areas receive less than 0.5".

Recent guidance has trended a bit slower with the upper low
departure, suggesting a bit greater chance at lingering showers on
Wednesday across the east 1/3 to 1/2 of the region. The gap between
precipitation systems seems to be shrinking because the 00z models
have also sped up the late week system suggesting convection may
return to the region by Thursday afternoon as mid-level height falls
occur. This system keeps showers and storms around through Friday,
before likely departing the region by Saturday. There are a few
ensemble members lingering some energy behind within the weak trough
to keep small PoPs going on Saturday though.

Next Sunday there is considerable model spread whether a southern
stream shortwave moves over the TN Valley or if upper ridging will
be in place. Some ensemble members including the deterministic ECMWF
suggest some mid-level energy from the late week system hangs back
across the southwest U.S. and then drifts east towards our area on
Sunday. Slightly more of the 00z members are suggesting this
compared to prior runs, which led to NBM PoPs nudging up into the
chance category. It`s quite possible the entire weekend is dry
though.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 608 AM CDT Mon May 13 2024

Shower activity will gradually increase today into tonight,
accompanied by a few thunderstorms. TSRA is more likely late
this evening and overnight, especially at KCGI/KPAH, but we could
see isolated storms this afternoon. Low MVFR cigs across
Arkansas will spread northeast from late morning through the
afternoon. Guidance hints even lower cigs into IFR range are
likely by later evening and overnight. Vsby reductions also
expected, mainly in MVFR range, but may be briefly lower in
heavier convection. Winds will primarily be out of the S-SE
though the period.

&&

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

&&

$$

UPDATE...SP
DISCUSSION...SP
AVIATION...SP