526
FXUS61 KRLX 300545
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
145 AM EDT Sun Jun 30 2024

.SYNOPSIS...
Very warm and humid, with strong, heavy storms possible tonight
into Sunday. A cold front brings an end to threat Sunday
afternoon. Dry to start the week, becoming hot again Tuesday.

&&

.NEAR TERM /THROUGH TODAY/...
As of 1035 PM Saturday...

Severe Thunderstorm Watch 843 was allowed to expire, as a strong
cell arrived from the west coming out of Severe Thunderstorm
Watch 845. Fed by 90-degree evening heat and sultry humidity, it
caused tree damage and isolated street flooding in northeast
KY, but has since weakened despite the juicy air that still
resides ahead of it. Some further weakening is possible, but it
will traverse central WV with heavy rain, frequent lightning
and gusty winds.

It is unclear whether another cluster of thunderstorms will
develop overnight. Otherwise, additional showers and
thunderstorms may fire up east of the advancing cold front
Sunday midday and afternoon. The advancing front should limit
this convection to areas south and asst of the Ohio River.

As of 820 PM Sunday...

Convection associated with a series of mid-level short wave
troughs along the southern edge of the westerlies, ahead of a
cold front back across the Great Lakes and Midwest, was
gradually waning in intensity. Severe Thunderstorm Watch 483
could be let go a bit early if this trend continues.

However, very warm and humid air in place, evinced by 8 PM
temperatures still up around 90 F across southern portions of
the lowlands, not affected by thunderstorms yet today, dew
points in the lower 70s, and PW values in the 2-2.25 inch range,
will support convection on through the night tonight, along
with the locally heavy rainfall threat.

The heavy rain threat could be realized via repetitive storms
north where motion is faster, and slower moving storms south of
the southern edge of the westerlies, as evinced by one such
cell just west of the forecast area and just south of the Ohio
River, around 8 PM this evening.

Temperatures were raised tonight to reflect the very warm to hot
conditions this evening.

As of 440 PM Saturday...

Isolated strong to severe thunderstorms in north central WV have
warranted inclusion of this area in Severe Thunderstorm Watch
483, which extends eastward through the WV and MD panhandles.

The storms were the tail end of a line of storms that extended
northeastward through PA, and into a more general area of
showers in eastern NY and New England, all along a mid-level
short wave trough axis. Northern WV was at the southern edge of
this axis/westerlies and better deep layer shear. Strong heating
continued downstream of these storms amid sunshine.

That portion of the watch in our county warning area being the
tail end of it, it may not quite be needed all the way up until
its 02Z/10 PM EDT expiration time.

As of 140 PM Saturday...

Key Point:
* Severe storms and heavy downpours possible this afternoon
  and evening.

A few showers and storms are possible early this afternoon, then a
more organized line of convection is expected to arrive by late
afternoon and trudge east across the area through the evening while
a shortwave passes overhead and a cold front approaches from the
west.

Moisture will feed into the area out ahead of the front, allowing
precipitable water values to climb to 2 to 2.25 inches by the end of
the day. Such high moisture should support heavy downpours which
could create a few localized flooding issues in poor drainage or low-
lying areas. Along with moisture, daytime heating will contribute to
increasingly unstable conditions. During the late afternoon and
evening, moderate to strong instability is expected to support
isolated to scattered severe storms. The environment will be most
favorable for a damaging wind threat; however, there is also a low
(2-4%) risk for tornadoes in the northern third of the CWA.

At least a few showers and storms may persist overnight amid warm
and muggy conditions. On Sunday, more showers and storms form
ahead of and along the cold front -- which is expected to reach
southeast Ohio in the morning and then sweep east across the
CWA. A stronger storm or two could be possible during the
frontal passage, then precipitation should gradually taper off
from west to east behind the front during the latter half of the
day.

&&

.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
As of 100 PM Saturday...

The beginning of the new calendar month opens up with pleasant
weather in the wake of the weekend frontal passage. A brief
reprieve from the overbearing temperatures and dry weather will
arrive in the form of high pressure spreading over the Ohio
Valley. Afternoon highs are progged to only reach the upper 70s
in the central lowlands and the 60s along the mountains.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 100 PM Saturday...

Upper level ridging will continue to support dry weather on
Tuesday, with temperatures returning to seasonable for this time
of year.Pressure height rises will translate into a rise in
temperatures beginning on Tuesday and heading into highs
extending into the 90s across the lower elevations. The ridge
begins to flatten and sink down into the southern half of the
country on the 4th of July, making way for a frontal boundary
and its associated line of showers and storms. Models remain on
track with this boundary struggling to surpass the forecast area
on Thursday, becoming stationary over the area for the end of
the week. Maintained central guidance chance to likely POPs for
this timeframe, and held onto convection even during the
overnight hours due to the persnickety front hanging about
during the holiday weekend.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
As of 143 AM Sunday...

Radar imagery shows the bulk of convection associated with a passing
short wave, exiting the eastern mountains overnight. However, the
atmosphere remains very juicy and unstable, and convection may
develop overnight into early Sunday morning ahead of an arriving
cold front. Therefore, showers and storms are expected to continue
across the area through Sunday as the front advance southeast,
finally exiting the eastern mountains by 00Z Monday.

Any thunderstorm tonight into Sunday can produce strong wind gusts,
and brief periods of IFR/LIFR conditions.

MVFR stratocumulus develops before dawn Sunday. This stratocu will
gradually lift and break up from west to east Sunday afternoon.

Light south to southwest surface flow tonight, except strong and
gusty from the southwest to northwest in thunderstorms, will become
light west behind the prefrontal wind shift Sunday morning, and then
light northwest behind the cold front Sunday afternoon.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z MONDAY...


FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Amendments may be needed for lower flight
category within storms or heavy rain. IFR ceilings are possible
along the mountains Sunday morning.

EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH:   TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW:    TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.

DATE                              SUN 06/30/24
UTC 1HRLY       06   07   08   09   10   11   12   13   14   15   16   17
EDT 1HRLY       02   03   04   05   06   07   08   09   10   11   12   13
CRW CONSISTENCY  H    H    H    H    H    M    H    H    H    H    H    H
HTS CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    M
BKW CONSISTENCY  H    H    H    H    M    M    M    M    L    H    L    H
EKN CONSISTENCY  H    L    L    H    H    H    H    H    H    H    H    H
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    M
CKB CONSISTENCY  H    H    H    H    M    H    H    H    H    H    H    H

AFTER 06Z MONDAY...
IFR possible in stratus, at least in and near the mountains,
overnight Sunday night into Monday morning. Brief IFR possible
in showers and thunderstorms Thursday.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...None.
OH...None.
KY...None.
VA...None.

&&

$$

SYNOPSIS...MEK/TRM/JLB
NEAR TERM...TRM/JLB
SHORT TERM...MEK
LONG TERM...MEK
AVIATION...ARJ