098
FXUS63 KPAH 012127
AFDPAH

Area Forecast Discussion
National Weather Service Paducah KY
427 PM CDT Mon Jul 1 2024

.KEY MESSAGES...

- Potentially dangerous heat and humidity levels will return to
  the forecast Wednesday...and possibly continue for parts of
  the area into Thursday (Independence Day).

- Scattered to numerous thunderstorms are forecast at times from
  Wednesday afternoon through Friday afternoon. Some of the
  storms could be severe Wednesday afternoon and evening. Heavy
  rain and isolated flash flooding will also be possible.

- Drier, less humid, and cooler weather is forecast for next
  weekend, with only a small chance of showers and thunderstorms
  forecast late Sunday night.

&&

.UPDATE...
Issued at 423 PM CDT Mon Jul 1 2024

Updated Aviation discussion for 00Z TAF Issuance.

&&

.DISCUSSION...
Issued at 235 PM CDT Mon Jul 1 2024

Tonight through Tuesday...Excessively pleasant conditions will
continue this afternoon through tonight. A rare July opportunity
for open window weather is forecast tonight, with lows dipping
into the upper 50s to lower 60s. As surface high pressure
centered over the Great Lakes translates to the east, southerly
flow will increase Tuesday, bringing warmer temperatures. Highs
will reach the upper 80s to lower 90s. However, humidity levels
will still be fairly low through the daytime hours, keeping
heat index values in check. Dew point temperatures will rise
overnight, though. Combined with increasing cloud cover, low
temperatures Tuesday night will stay in the lower to middle 70s.

Wednesday through Friday...A transition to a more unsettled
weather pattern will begin late Wednesday and continue through
the end of the work week. This will be due to a cold front
approaching the region from the northwest then stalling across
the heart the region, which will allow for the development of
potentially several rounds of showers and thunderstorms.

Before the storms develop late on Wednesday, hot and very humid
conditions will return to the region as very strong heat and
moisture advection commences. This will allow high temperatures
to reach the lower to middle 90s on Wednesday. Combined with dew
point temperatures in the middle to upper 70s, widespread heat
index values of 105-110F+ are forecast Wednesday afternoon. This
would be firmly in the Heat Advisory range, and one will likely
be needed if nothing changes in the current forecast.

Ahead of the cold front`s arrival, very strong destabilization
will occur. With bulk shear values increasing along the frontal
boundary, initiation of organized storms will occur late
Wednesday afternoon into Wednesday night. At this time, the
storms look to fire along and north of I-64 and move to the
south and east. As it stands, SPC has much of southern IL,
southwest IN, and northwest KY outlooked with a slight risk of
severe thunderstorms. A marginal risk of severe thunderstorms
extends further south and west to the MO/AR and KY/TN borders.
At this time, damaging wind gusts from thunderstorm clusters and
lines looks to be the main threat, though some large hail will
be possible with storms that initially develop.

For Independence Day on Thursday into Friday, scattered to
numerous thunderstorms will remain in the forecast as additional
rounds of precipitation develop along the frontal boundary.
With PWAT and specific humidity values rising into the 95-99th
percentiles via at 01/00z NAEFS guidance, there will be plenty
of moisture to produce heavy rain. Training storms along the
frontal boundary will also result in the potential for corridors
of heavy rain and isolated flash flooding, especially near and
north of I-64. Latest WPC guidance shows a broad brush of 2-4"
from Perryville, MO, to Carbondale, IL, to Mount Carmel, IL.
Rainfall amounts taper down to 0.5-1.0" southward towards the
AR/TN borders.

Temperatures on Independence Day Thursday and Friday will be
dependent on rain and cloud cover. Right now, temperatures look
to reach the lower 90s in most areas on Independence Day, with
triple digit heat index values still likely for many areas.
Temperatures will cool slightly on Friday, but still reach the
upper 80s in most areas. As frontal boundary moves south of the
area, less humid air will gradually filter into the region
Friday night.

Saturday and Sunday...A return to drier and more comfortable
temperature and humidity levels is in the forecast for next
weekend. High temperatures look to reach the upper 80s to near
90 degrees both days, but dew point temperatures look to stay in
the 60s, which will keep the heat index values from getting too
outrageous. A small chance of showers returns to the forecast
late Sunday night as our next disturbance approaches from the
northwest.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 423 PM CDT Mon Jul 1 2024

Surface high pressure will move east from the Great Lakes to New
England. In response, winds will veer and return flow
southerlies will commence again starting tmrw. Satellite and
time/height cross sections suggest the dry air in the lower half
of the column remains strong for another package, so just some
occasional upper ridge topping mid to high level SCT-BKN bases
are expected.

&&

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

&&

$$