770
FXUS63 KPAH 030441
AFDPAH

Area Forecast Discussion
National Weather Service Paducah KY
1141 PM CDT Thu May 2 2024

.KEY MESSAGES...

- Very warm temperatures continue, with humidity increasing
  through the weekend. Daily chances of showers and
  thunderstorms with a very good chance of rain and storms
  tonight.

- Scattered storms over the weekend lead into a potentially
  active period of several days Monday night through Wednesday
  where it appears at least some potential will exist for severe
  thunderstorms and heavy rainfall.

&&

.DISCUSSION...
Issued at 129 PM CDT Thu May 2 2024

The weather is doing a fantastic summer impression on this early
May day. Highs are working well into the mid 80s with dewpoints
around 60 degrees. Atmospheres fairly stable right now based on
model soundings and cu behavior on satellite, but a slug of
deeper moisture/warm advection and slight jet level ascent will
work this way later this afternoon into this evening bringing
with it a good chance for stratiform rain and convective showers
and a thunderstorm or two. With PWATs stretching to 1.6 to 1.7
inches rainfall rates will be efficient/heavy but our ground
conditions are such that flooding still appears unlikely unless
multiple storms really root in over the same area.

The stronger WAA/isentropic lift ends by early morning as north
winds scour out low level moisture just a little. I think we
will be more dry than not during the day but with just a kiss of
jet level ascent and humidity kept pops in, increasing with
daytime heating. More warm air and moisture advection moves in
in the evening and showers and storms will likely accompany
this.

A sharp shortwave trough then approaches Sunday. Low-level
moisture recovers with dewpoints in the upper 60s. MLCAPE values
rise to about 1500-2000 J/kg. Deep layer shear is marginal for
severe and low level shear holds off until after large scale
ascent appears less favorable. It does look plausible a severe
storm or two may form Sunday afternoon and evening given that
mid-level lapse rates may overachieve from model consensus given
the sharpness of the shortwave. Net height rises then build in
behind the shortwave which will likely keep us on the drier side
Monday despite a surge in low level moisture as a powerful and
large negatively-tilted shortwave trough moves in off the Rocky
Mountains. This will mark an extended period where the larger
synoptic scale pattern will be favorable for heavy rain and
severe weather. Shear improves Monday night with dewpoints
approaching 70 degrees. Strong low and deep layer shear is in
place Tuesday with dewpoints remaining around 70 degrees. There
are still some differences in the GFS/ECMWF handling of the
upper trough over this region which would have large factors in
the overall severe weather potential for the area. Ongoing
convection and potential modification of the airmass would be a
concern too, but we will absolutely need to watch Tuesday for an
all-hazards severe potential given the day to day model trends.
General troughiness persists and things look to sort of re-load
for Wednesday with strong deep and low level shear and ample
instability. Thursday the GFS clears out the area where the
ECMWF holds off on FROPA.

Similar to 12-24 hours ago picking out exactly if and when
things will come together and how convection will evolve day to
day is just impossible at this range for the Monday Night to
Wednesday timeframe, but it has the look of a pattern that could
produce a multi-day severe weather and heavy rain threat with
subtle shortwave troughs working in over very rich low level
moisture.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1123 PM CDT Thu May 2 2024

Intermittent rain showers are expected through the rest of the
night at each TAF site before shifting east of the area by mid
morning. It is still possible that some lightning may occur, but
the chances are low enough to leave out of this issuance.
Additional isolated showers and storms may develop Friday
afternoon, impacting mainly the eastern sites. Chance are fairly
low of that happening at this time. Some MVFR/IFR conditions are
expected later tonight into Friday morning.

&&

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

&&

$$

DISCUSSION...JGG
AVIATION...KC