407
FXUS63 KJKL 160420 AAB
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
1220 AM EDT Thu May 16 2024

.KEY MESSAGES...

- After a lull in shower and thunderstorm chances on Thursday,
  chances return to close out the week.

- Near normal to slightly above normal temperatures are expected
  to return for Thursday through the middle of next week.

&&

.UPDATE...
Issued at 1217 AM EDT THU MAY 16 2024

Hourly grids have been freshened up based on recent radar,
satellite, and radar trends. Fog has developed where there have
breaks in the clouds with some low stratus also reported. With
additional breaks in the clouds expected overnight, light winds,
and small dewpoint depressions, coverage will likely increase and
the fog should become dense in some locations.

UPDATE Issued at 835 PM EDT WED MAY 15 2024

Hourly grids were updated based on recent observations and radar
trends. Overall, with the loss of daytime heating, coverage of
showers should wane through late this evening. Following the
recent rainfall, any breaks or areas of clearing should promote
fog formation, and it is probable this would become dense
overnight, especially in valleys.

&&

.SHORT TERM...(This evening through Thursday night)
Issued at 410 PM EDT WED MAY 15 2024

Isolated to scattered showers and storms will persist across the
area through early this evening, before steadily tapering off after
dark. The last bits of rain should be exiting to our east late this
evening. A couple of counties in our far east may see isolated
showers and storms from time to time on Thursday, especially in the
late morning to early afternoon time frame, as moisture wraps around
the back side of a departing upper level low pressure system. It is
this low that will continue to bring rain to parts of the area
through late this evening before it moves off to our east overnight.
Cloud cover will remain in place through tonight, before finally
thinning out on Thursday. We should see partly cloudy skies on
Wednesday, which should allow temperatures to warm several degrees
higher than today, yielding highs in the upper 70s for most
locations around eastern Kentucky. A few spots may even reach 80.

Another area of low pressure will approach from the west late
Thursday night, and will cause and increase in clouds late Thursday
night into early Friday morning. However, we should still see a long
enough period of mostly clear skies to allow for small ridge valley
temperature split across the area. Nothing drastic, but the
differences will likely show up in obs around the area by Friday
morning. Most of the models area keeping precipitation out of our
area until early to mid-morning Friday. That being said, based on
current trends, decided to hold off on introducing precip to our
western counties before 12Z Friday. Winds should be light and
variable through out the period. We are expecting no weather
concerns in the short term. Keep in mind that any thunderstorm could
produce cloud to ground lighting at any time along with locally
heavy rainfall, so be on the look out if out and about while storms
are around this afternoon and this evening and go indoors if you
hear thunder. If you can hear thunder, you`re close enough to the
parent storm to be hit by a lightning strike.

.LONG TERM...(Friday through Wednesday)
Issued at 410 PM EDT WED MAY 15 2024

Models are indicating an upper level split flow expected across the
CONUS at the start of the period, with the southern portion of the
flow having troughiness over the south central CONUS along with an
embedded upper low. While there is agreement for the regime to shift
east with time, there is not good agreement on how quickly it
happens and where the upper low is positioned as it happens. That
being the case, a model blend will wash out details, but that is the
best that can be done at this point. In the lower levels, initial
flow north off the gulf will allow for plenty of moisture
availability for the advancing upper level trough/low. However,
there is also uncertainty regarding the track/position of any
surface low associated with the upper level low. The advancing upper
level system will take advantage of moisture availability and
produce showers and thunderstorms for our area at times, but only
broad brushing can be done for the POP at this point due to
uncertainties. It does appear that by Sunday night there should be
little if any precip left in our area as whatever semblance of
the system that exists departs. A decreasing POP trend will be
used for Saturday night and Sunday leading into a dry forecast for
Sunday night.

Ridging at the surface and aloft then transitions east over the
region Sunday night through Monday night, with little if any
chance for rain. Beyond this, a shortwave trough aloft is expected
to approach and pass over Tuesday night and Wednesday, with the
bulk of the wave to our north. This supports a surface cold front
which both the GFS and ECMWF pass through our area on Wednesday.
Only light precip is generated locally in the models, with the
best upper level support weakening and shifting to our north as
the system goes by. Won`t carry anything more than chance POP for
Tuesday night and Wednesday at this time.

&&

.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
ISSUED AT 840 PM EDT WED MAY 15 2024

Isolated to scattered showers are working across the CWA this time
as well as surrounding portions of the OH Valley and Southern
Appalachians. These should gradually wane over the next 3 to 5
hours. Within any of the heavier showers, MVFR or IFR reductions
are expected at least briefly. However, by the 04Z to 07Z
timeframe, light winds and some breaks in the clouds are
anticipated and this should set the stage for fog down to MVFR
and IFR and eventually LIFR or even to or below airport mins for a
few hours between 08Z and 13Z. Assuming clearing all the TAF
sites would be affected by this as LAMP guidance suggests. Between
12Z and 15Z, the fog and any low stratus that may also form will
gradually begin to lift and dissipate, with most areas likely to
experience VFR by 18Z and once conditions improve to VFR in a
location they will persist to end the period.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...JP
SHORT TERM...AR
LONG TERM...HAL
AVIATION...JP