668
FXUS61 KRLX 080747
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
347 AM EDT Wed May 8 2024

.SYNOPSIS...
Daily chances for showers and storms continue, with the
frequency of storms posing concern for localized flooding.
Severe storms are possible today and again Thursday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 345 AM Wednesday...

Key Points:

 * Early morning convection tracks southward over the next
   several hours.

 * Brief lull in activity this morning into the afternoon,
   before strong to severe storms return heading into tonight.

 * Storms once again will have the potential for damaging wind
   gusts, large hail, tornadoes, and heavy downpours.

The forecast area remains in the trenches of strong to possibly
severe storms early this morning as a multi-segmented line of
convection drapes southward. At the time of writing, a cluster
of storms extended from eastern Kentucky up into southeast Ohio
and becoming primarily outflow driven. Should see further
destabilization over the next few hours as activity drifts into
a more stable airmass, but will have to continue monitoring for
hydro concerns. Precipitation rates of 1-2 inch/hr were noted
with activity pressing into the forecast area and is currently
entering into an area that has received decent amount of
rainfall already these past several days.

After sunrise, the line of weakening activity is slated to be
crossing down through the southern coalfields into Virginia,
with a further southern push out of the forecast area expected,
This should allow for a lull in convective trends into the early
afternoon before active weather reappears later in the period.
Until then, skies look to clear from north to south throughout
today, allowing for afternoon temperatures to climb into the low
80s across the lower elevations. Coupled with dew points in the
60s still festering over the area, another round of moist and
unstable conditions will be available for convection that
develops upstream during peak heating hours.

A surface low will aid in storm development along a stalled
frontal boundary nestled over the region. Hi-res CAMs afternoon
activity will start off in the Tennessee/lower Ohio Valleys and
propagate eastward through Kentucky and West Virginia by late
this evening into tonight. All hazards remain in play within
today`s convective setup, as diurnal heating will promote local
destabilization amidst the warm and moist airmass continuing to
retain residency over the region via deep southwesterly flow.
As has been the case this evening, radar trends may become
sustained by outflow boundaries, but nonetheless will allow for
active weather to stretch well into the overnight hours tonight.

Localized flooding concerns remains at the forefront of weather
concerns within the period as depleted FFG becomes tested by
rounds of showers and storms. 1 hour FFG of 0.75-1.25 inches
remains noted across the Ohio River Valley early this morning,
with another branch of saturated soils from southwest Virginia
up into parts of southern West Virginia. Opted to extend the
Flood Watch to encompass our VA counties as well as McDowell and
Wyoming Counties in WV due to expected rainfall totals arriving
late tonight into this area, which has already seen instances
of flash flooding days prior. This Watch will remain in effect
until Thursday morning.

&&

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

This period starts off with a surface low along the western
flank of our CWA border. This feature will have already lifted
a warm frontal boundary north of our area while we remain in the
warm sector with ongoing shower and storm activity. By this
time frame, during the late morning to early afternoon,
instability will be lacking and there will even be a small cap
along with some low to modest shear. Severe potential will be
slim, however with high DCAPE values, long skinny CAPE and super
saturated low to even upper levels, flooding with be the main
threat, not to mention just over 1.5 inches of PWAT values.

The flood watch will be already inched into this period and
will likely be extended further into this period for the rest of
Thursday which is a good idea due to the aforementioned weather
parameters in place. An excessive rainfall threat will
accompany Thursday as well covering almost our entire CWA with
a marginal threat insinuating any thunderstorm will be capable
of producing heavy showers which may promote some localized and
isolated flash flooding issues, hence the main threat.

Not too far behind is the forecast cold front which is slated to
move through by 0Z which will then filter in drier air tapering
off activity for the late afternoon and evening. There will be
chances for showers on the table still due to wrap around flow
from the surface low although no thunderstorm activity should
take place. This will go on through Friday as an upper level
trough rides in right behind the surface low and keeps unsettled
weather on the table for us.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 200 AM Wednesday...

Surface high pressure will then move in for early morning to early
afternoon on Saturday. This will be a short break due to another
surface low coming inbound from the northwest which will affect
the rest of the day on Saturday. More thunderstorm chances will
remain for the rest of the day going into Sunday morning. The
rest of the period looks to be slightly active, however models
are in disagreement on just how active. The GFS seems to be the
most active therefore went with a favored heavier weighted
blend with that model and left shower chances for the rest of
the period with diurnal thunderstorm activity on tap as well.

&&

.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
As of 133 AM Wednesday...

A line of showers and thunderstorms has arrived into the Ohio
River Valley at the time of writing, and is anticipated to glide
southward through the forecast area during the early morning
hours. Accompanying LLJ will impose a period of LLWS across most
TAF sites to begin the period, then trailing down in the wake of
convection. Outside of a brief uptick in winds and a quick
downpour, showers and storms passing over an airfield early this
morning may cause a quick reduction in surface vsbys.

Ceilings behind the line of storms drop down to MVFR during the
predawn hours, then should recover to low end VFR after sunrise.
Should generally see a quiet morning/early afternoon today
before convection picks back up in the late afternoon and
evening. Storms once again could promote strong wind gusts,
hail, and a quick spin-up tornado and is progged to prevail into
the overnight hours late Wednesday into early Thursday morning.
Similar trend in ceilings for late in the current TAF period,
where MVFR and pockets of IFR spread into the area before mixing
out once more Thursday morning.

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

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Timing of convection may vary from
forecast. Timing/development of MVFR/IFR ceilings this morning
may vary.

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                         WED 05/08/24
UTC 1HRLY       07   08   09   10   11   12   13   14   15   16   17   18
EDT 1HRLY       03   04   05   06   07   08   09   10   11   12   13   14
CRW CONSISTENCY  H    M    M    H    L    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    M    L    H    H    H    H    H    H    H
EKN CONSISTENCY  M    H    H    H    H    L    H    H    H    H    H    H
PKB CONSISTENCY  H    H    M    M    H    H    M    H    H    H    H    H
CKB CONSISTENCY  H    H    M    H    H    H    H    H    H    H    H    H

AFTER 06Z THURSDAY...
IFR conditions at times in showers and thunderstorms into
Thursday, and in fog and stratus Friday morning.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...Flood Watch through Thursday morning for WVZ005>009-013>017-
     024>026-033-034.
OH...Flood Watch through Thursday morning for OHZ075-083>087.
KY...Flood Watch through Thursday morning for KYZ101>103-105.
VA...Flood Watch through Thursday morning for VAZ003-004.

&&

$$

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