351
FXUS61 KRLX 290631
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
231 AM EDT Sat Jun 29 2024

.SYNOPSIS...
Warm and increasingly humid today with storm potential. Severe
storms and heavy rain are possible today and Sunday. A cold front
crosses Sunday. Dry the new work week, becoming hot.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 230 AM Saturday...

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

A cold front approaches from the west late tonight into early
Sunday morning. Meanwhile, low level southwest flow will pump
moisture and warm air to the area with PWATs exceeding 2.0
inches, H850 theta-e values exceeding 340K and dewpoints in the
mid 70s. These moisture ingredients will destabilize the
atmosphere with the heat, providing CAPE exceeding 2500 J/Kg.
Guidance shows deep layer shear about 25-30 knots across the
northern half of the CWA this afternoon and evening. In
addition, guidance suggests an upper level short wave should
arrive around 8 PM to the Mid Ohio valley. This wave will provide
extra forcing to sustain strong to severe thunderstorms, more
numerous across the northern half of the area where deep layered
shear is higher. The best potential for isolated to scattered
severe storms is expected to be in the late afternoon through
the evening. While damaging winds will be the primary concern,
there is also a non-zero risk for tornadoes or hail.

Local soundings show a robust, moist and tall CAPE feature with
equilibrium levels about 45 kft. This will allow for strong to
severe updrafts conducive to heavy downpours and associated
localized flooding over poor drainage areas or locations
impacted by multiple storms.

Afternoon temperatures will rise into the lower 90s across the
lowlands, ranging into the mid 70s higher elevations. A muggy night
is anticipated with dewpoints in the low to mid 70s. Lows will range
from the low to mid 70s lowlands, into the mid 60s higher
elevations Saturday night.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
As of 215 AM Saturday...

A cold front associated with a low moving across the Great
Lakes will be exiting the area toward the east to start this
period off on Sunday morning. Some shower and storm activity
will be possible during the day time on Sunday with some strong
to severe storms possible before the front kicks out.

Looking at soundings there is plenty of CAPE under partly
cloudy skies with no CIN meaning prolonged updrafts with enough
upper level wind support and modest wind shear of 30KT+ could
promote some long duration storms. DCAPE is solid along with
high PWATs and mid to upper level moisture which will promote
heavy downpours that could lead to localized water issues,
especially in low lying or flood prone areas.

The main threats seem to be damaging wind and heavy downpours.
WPC has us in a marginal threat for excessive rainfall and SPC
has us in a marginal threat for severe storms. This will mainly
be for the afternoon until the front exits toward the mountains
by the evening.

Temperatures will go from slightly above seasonable on Sunday
to a more less than seasonable and cooler day on Monday with
colder air filtering behind the front along with broad high
pressure building in and supported by upper level ridging.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
As of 215 AM Saturday...

High pressure dominates into the long term period shielding the
area from any unsettle weather well into the new work week.
This will allow for mainly clear skies and a warming trend
through midweek.

By Wednesday afternoon, chances for shower and storms returns.
Models have a good handle on a cold front passing through on
Thursday, however they diverge thereafter. Ideally diurnal
thunderstorms will prevail for the rest of the week and into the
weekend. Southerly flow dominates the rest of this period
influencing the region with plenty of warm air advection and a
strong moisture flux from the south.

&&

.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
As of 128 AM Saturday...

Widespread VFR conditions expected through at least 16Z Saturday.
Radar imagery shows scattered light showers, most not reaching the
ground across OH, moving east into WV. Do not expect restrictions
with this activity overnight.

However, unstable conditions emerge this afternoon and evening as
southwest flow advects plenty of moisture to destabilize the
atmosphere allowing for afternoon convection. In addition, an upper
level disturbance will bring forcing to sustain strong to severe
updrafts/downdrafts Saturday afternoon and evening. Brief periods of
IFR conditions under strong gusty winds can be expected under or
nearby thunderstorms with more confidence across the northern sites.
Using Hi-res CAMS models, timed and coded thunderstorms with PROB30
during the late afternoon and evening hours at PKB and CKB. Other
sites may be affected as well, but confidence runs lower at this
time so coded VCTS for now.

SPC maintains a slight risk for severe thunderstorms Saturday
afternoon across northern and central portions of the area, with a
marginal risk farther south. The main severe threat with
thunderstorms will be damaging wind gusts and may last on into
the evening hours.

Light south to southeast surface flow tonight will become light south
to southwest on Saturday. Moderate south flow aloft tonight will
become light south to southwest on Saturday. Low level wind shear is
possible overnight, particularly where gusts do not mix to the
surface, which would most likely be across the lowlands. The low
level flow should preclude fog formation overnight tonight.

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

FORECAST CONFIDENCE: High.

ALTERNATE SCENARIOS: Amendments may be needed in showers and
especially stronger thunderstorms Saturday, most likely in the
afternoon and 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.

DATE                              SAT 06/29/24
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    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    M    M    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 06Z SUNDAY...
Brief IFR possible with thunderstorms Saturday night and
Sunday.

&&

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

&&

$$

SYNOPSIS...ARJ/JZ
NEAR TERM...ARJ
SHORT TERM...JZ
LONG TERM...JZ
AVIATION...ARJ