586
FXUS63 KPAH 171122
AFDPAH

Area Forecast Discussion
National Weather Service Paducah KY
622 AM CDT Fri May 17 2024

.KEY MESSAGES...

- A Flood Watch remains in effect until 7 PM CDT for parts of
  southeast Missouri, southern Illinois, and western Kentucky.
  Additional rounds of heavy rain through the morning hours
  could bring flash flooding to parts of the Flood Watch area.

- We will gradually dry out and warm up this weekend, with high
  temperatures reaching the middle to upper 80s by Sunday.

- Next week will be very warm and muggy, with daily
  thunderstorm chances returning to the forecast beginning
  Tuesday through the end of the work week.

&&

.UPDATE...
Issued at 621 AM CDT Fri May 17 2024

Updated Aviation discussion for the 12z TAF issuance.

&&

.DISCUSSION...
Issued at 328 AM CDT Fri May 17 2024

Today and Tonight...The ongoing Flood Watch looks to be on
track. An axis of heavy rain and thunderstorms across southeast
MO is gradually shifting east into far southern IL and far
western KY. This activity is developing along a convergence area
that extends from WSW to ENE roughly parallel to the MO/AR and
KY/TN border. MRMS QPE shows a band of 2-4" of rain has fallen
over the last six hours across Butler, Stoddard, and Scott
Counties in southeast MO.

Short- term model guidance brings this activity into the rest
of the Flood Watch through the rest of the morning hours, before
tapering off this afternoon. With PWAT values still at 1.5
inches, model soundings showing a classic skinny CAPE heavy rain
profile, and a boundary to initiate training convection, the
heavy rain threat looks to continue for several more hours.
Therefore, no changes are planned to the Flood Watch. However,
if the heaviest rain exits the Flood Watch area by early this
afternoon, it will likely be able to be canceled a bit earlier
than its scheduled 24z expiration time.

Clouds and rain will limit high temperatures to the lower to
middle 70s across the area. Dew point temperatures in the lower
to middle 60s will make it feel a bit sticky, however.

Tonight, isolated to scattered showers and storms will gradually
become confined to eastern parts of the forecast area over
southeast IN and the KY Pennyrile, as surface low pressure
passes just to our south and east across the TN River Valley.
With a saturated boundary layer and very light winds, areas
that see clearing skies tonight will likely see fog development,
some of which could be dense. Low temperatures tonight will
fall into the upper 50s to lower 60s.

Saturday through Monday...The weekend into early next week will
see a gradual drying trend with PoPs and a warming trend in
temperatures. With the surface low still positioned just east of
the region, isolated to scattered shower and storm development
will occur, primarily over southwest IN and the KY Pennyrile.
Areas further to the west should be mainly dry with mid-level
heights rising quickly. High temperatures will range from the
lower 80s to upper 70s from west to east on Saturday.

Sunday and Monday will be dry but very warm and a bit muggy.
With surface high pressure over the Mid- and Deep South, and 850
mb temperatures near 20C, high temperatures will have no
trouble reaching the middle to upper 80s. Overnight lows will
dip into the lower to middle 60s.

Tuesday through Thursday...A transition to more active pattern
looks to begin Tuesday and persist through end of the forecast
period. The forecast area will be near a SW-NE oriented baroclinic
zone, with a parade of disturbances bringing renewed daily
chances of showers and thunderstorms. The most significant
system looks to impact the region Wednesday into Thursday, when
surface low pressure is progged to deepen and move NE from the
southern Plains into the Midwest. With a neutral to negatively-
tilted H5 trough and strong moisture and heat advection off the
Gulf of Mexico present, there could be the potential for some
strong to severe storms with this system. However, given we are
still several days out, it is difficult to put a lot of stock in
any one solution at this time.

The warmest temperatures of the season are forecast Tuesday,
with highs reaching the upper 80s to lower 90s. Dew point
temperatures will climb into the middle to upper 60s, so it will
certainly feel like early summer. Temperatures will cool
slightly on Wednesday and Thursday as PoPs and cloud cover
increase. Overnight lows will be on the stuffy side, though, in
the upper 60s to lower 70s.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 621 AM CDT Fri May 17 2024

Widespread light to moderate rain showers will impact the
terminals through about 15-18z today, when coverage will become
more scattered in nature. Cannot rule out a few thunderstorms
as well, but expected coverage was too low to include at this
time. As the rain winds down, low stratus will with MVFR cigs
will arrive and persist through late afternoon, followed by
improvement around 00z Saturday. Winds will be light from the S
to SE, then become calm tonight.

Where skies clear late tonight (after 06z) fog will develop,
some of which will be dense. Was confident enough to include
LIFR fog restrictions as CGI, PAH, and MVN beginning around 09z
Saturday. Started with MVFR fog at EVV and OWB where stratus
might linger.


&&

.PAH WATCHES/WARNINGS/ADVISORIES...
IL...Flood Watch through this evening for ILZ088>090-092>094.
MO...Flood Watch through this evening for MOZ108>112-114.
IN...None.
KY...Flood Watch through this evening for KYZ001>009.

&&

$$

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