534
FXUS61 KRLX 031722
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
122 PM EDT Wed Jul 3 2024

.SYNOPSIS...
High pressure brings hot weather this afternoon. Chance of rain
arrives late this afternoon and tonight. More active weather is
expected July 4th and Friday with cold fronts.

&&

.NEAR TERM /THROUGH THURSDAY/...
As of 120 PM Wednesday...

A Heat Advisory remains in effect for portions of WV, southeast
OH and northeast KY through this evening with heat index values
reaching around 100 during the hottest part of the afternoon.
Widely scattered thunderstorms will be possible late this
afternoon and this evening in southeast Ohio ahead of a 500-mb
shortwave. However, 0-6km shear will be weak (only 20-25 kts)
and instability will be weak to marginal (MLCAPE 500-800 J/kg).
Thunderstorms should lose intensity as they approach and track
east of the Ohio River, where the instability will be even
weaker.

Severe weather potential will be a little greater Thursday with
models showing MLCAPE reaching 1,000-1,200 J/kg in parts of WV
and northeast KY. 0-6 km shear is still expected to be fairly
weak (only around 25 kts in most spots). As ripples of 500-mb
vorticity approaches from the west, a few severe thunderstorms
will be possible during the day, with the main threat being
damaging winds. With weak shear over most of the area, severe
thunderstorms may have difficulty organizing, potentially causing
them to be short lived. The SPC currently has a marginal risk
of severe weather over the region for Thursday. In addition,
there is a marginal risk of excessive rainfall. PWATs are
projected to be anywhere from 1.8-2.2 inches across the region,
which can lead to heavy downpours. We will have to watch for the
potential for localized flooding if thunderstorms begin to
train over the same areas.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
As of 200 AM Wednesday...

Key Points:

  * Rounds of showers and thunderstorms Thursday with cold front.

  * Some storms could be strong or severe.

  * There is a marginal risk for severe weather Thursday.

  * There is a marginal risk for excessive rainfall on Thursday.

Stationary front across Ohio gains some steam and slowly moves
eastward across the area Thursday. Showers and storms will
overspread the area as through out the day as it makes its eastward
journey. Some storms will be strong or severe with damaging winds
and maybe some hail. SPC has the entire forecast area outlooked for
a marginal risk of severe weather.

NAM shows some fairly impressive CAPE (SB,ML and MU) profiles
between 1,000-3,000 J/Kg across the area Thursday during peak
heating. Values greater than 3,000 J/Kg could exist in a CAPE bulge
across the southern coalfields in the afternoon and this could be an
area to watch for higher risk of severe thunderstorms. Some
uncertainty exists with whether these values will come to fruition
as cloud cover could exist throughout the day preventing
temperatures from being too hot and creating a cap for any strong
convection. Regardless, temperatures look to be in the mid to high
80s across the lowlands with the mountains ranging between the mid
70s and mid 80s. These temperatures will be dependent on the amount
of clearing that occurs.

Surface to 500MB bulk shear looks to remain confined across our SE
Ohio counties and along the Ohio River until later in the afternoon
as the front and surface low push through. Values are forecasted to
be between 30-45kts across this area, which is decent enough to
maintain storm longevity and provide at least a minuscule tornado
threat depending on the positioning of a surface low or vort max;
the main threats remain to be damaging winds and small hail though.

Heavy rainfall will be the main concern with this system as it is
slow moving and precipitable water will be around 2.00" inches
across the bulk of the area, which is a decent amount of water. As a
result, LCLs look to be fairly low (500 to 1,000 meters)resulting in
lower cloud bases. Localized to isolated flash flooding issues will
be on the table, especially for areas that receive a lot of rain
Wednesday night. WPC has the entire area outlooked for a marginal
risk of excessive rainfall on Thursday.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 1230 PM Wednesday...

With a cold front off to the east Saturday morning, any
lingering precipitation over eastern West Virignia and
southwestern Virginia will tapper off. A high pressure system
will then build over the area, providing seasonable temperatures
for Saturday afternoon. The high will provide dry weather for
Sunday, with temperatures increasing slightly.

As the high shifts off to the east on Monday, some southerly
moisture will allow for a chance of showers and thunderstorms,
along with above normal temperatures.

Models diverge some for Tuesday, with some showing a cold front
Tuesday or Tuesday night, while others keep the front to our
north. Either way, moisture over the area should allow for a
decent chance of showers and thunderstorms.

&&

.AVIATION /17Z WEDNESDAY THROUGH SUNDAY/...
As of 106 PM Wednesday...

Conditions will remain mostly VFR into tonight. A stray
thunderstorm is possible this evening, with the best chance at
KPKB, can briefly reduce visibility to IFR in a heavy downpour.
VFR should continue in most spots overnight, but IFR dense fog
is expected in the sheltered mountain valleys after 06Z and
before 12Z, particularly at KEKN. Scattered showers and
thunderstorms will become more likely by mid-to-late morning
Thursday.

Winds can occasionally gust from the southwest this afternoon
at 15-25 kts. Winds should gradually relax overnight. Expect
west-southwest winds again Thursday.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z THURSDAY...

FORECAST CONFIDENCE: High.

ALTERNATE SCENARIOS: Convection may develop around 21Z bringing
restrictions at least to PKB before 00Z this evening.


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.

UTC 1HRLY       17   18   19   20   21   22   23   00   01   02   03   04
EDT 1HRLY       13   14   15   16   17   18   19   20   21   22   23   00
CRW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
HTS CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
EKN CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
CKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H

AFTER 18Z THURSDAY...
Brief IFR possible in showers and thunderstorms Thursday and
Friday.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...Heat Advisory until 8 PM EDT this evening for WVZ005>009-
     013>015-017-025-026.
OH...Heat Advisory until 8 PM EDT this evening for OHZ066-067-075-
     076-083>087.
KY...Heat Advisory until 8 PM EDT this evening for KYZ101>103.
VA...None.

&&

$$

SYNOPSIS...RPY/JMC
NEAR TERM...JMC
SHORT TERM...LTC
LONG TERM...RPY
AVIATION...JMC