311
FXUS61 KRLX 051357
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
957 AM EDT Fri Jul 5 2024

.SYNOPSIS...
A thunderstorm complex is likely to cross this afternoon and
evening. A cold front crosses overnight into Saturday, with
drier weather in store for the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 950 AM Friday...

Full sunshine, especially across the southern half of the
forecast area will allow significant destabilization through
early this afternoon ahead of an advancing shortwave. Convection
associated with this feature is moving through central KY and
may diminish somewhat as it moves farther east through early
this afternoon before rekindling as it reaches out western
counties around 3 PM. With the forcing from the aforementioned
shortwave, expect activity to continue/develop into a linear
structure with bowing segments with wind damage as the primary
threat. Although low level turning is minimal, any northeasterly
surges in this line will need to be monitor for brief QLCS
tornadoes as southwesterly 0-3KM shear vectors approach 30KTs.
With the morning update SPC has added a 15% risk for wind for
much of the forecast area, with the primary threat likely
affecting the Metro Valley from 3 PM to 5 PM; would not be
surprised to see a 2% tornado area added with the afternoon
update.

As of 555 AM Friday...

Upon further review, issued a heat advisory for the central and
southern lowlands of West Virginia from noon to 5 PM this
afternoon. Even with the lower dew points, there are still
enough spots with heat indices of around 100, and opted to avoid
an even more shotgun issuance. Sunshine ahead of developing or
approaching thunderstorms early this afternoon should easily
provide the necessary heating. The thunderstorms should
intercept the heat by 5 PM.

As of 345 AM Friday...

Isolated showers continue to form across northern WV early this
morning, ahead of a mid-level short wave trough and south of its
associated surface low pressure center passing to the north.
This development will end west to east through daybreak, as the
system exits.

Dry weather than takes hold in the wake of this system for the
balance of the morning and midday, as a mid-level ridge
crosses. After that, where shower and thunderstorm development
takes place this later this afternoon, in response to a
mid/upper level short wave trough arriving from the west,
depends upon where a weak boundary ends up in the wake of the
morning system. This is expected to be from west to east across
central portions of the area, so late afternoon shower and
thunderstorm development is most likely across roughly the
southern half of the area.

1-2 KJ/kg of CAPE and 0-6/0-8km bulk shear up to 50 kts
suggests marginally severe storms are possible. Timing could be
earlier if a line moving eastward into and across Tennessee and
Kentucky this morning hold together, versus falling apart and
then reforming this afternoon. Either way, damaging wind gusts
are the main threat with a line or line segments.

With PW values in excess of two inches, heavy to locally
excessive downpours are possible with these storms, yielding a
flashy high water threat. Will continue to highlight the strong,
heavy thunderstorm threat in the HWO, for later this afternoon
into this evening

Showers and thunderstorms are then possible most anywhere
tonight ahead of a cold front and another mid/upper-level short
wave trough. The severe threat with this will be little or
none, especially south, where the atmosphere is worked over by
the earlier convection later today. Patchy fog is then likely to
form again overnight tonight.

Temperatures today could top out a bit early this afternoon
where convection develop or arrives from the west. Either way,
have lowered dew points a bit. Still near the higher end of the
guidance envelop, this keeps maximum apparent temperatures in
the mid to upper 90s, just shy of heat advisory criteria.
Temperatures tonight bottom out a bit above normal, with the
cold front just arriving by morning.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
As of 245 AM Friday...

Only the chance for some showers and drizzle will remain Saturday
morning as a cold front pushes eastward out of the area. Clearing
skies and drier weather will commence as high pressure swiftly
rushes in to fill the gap.

This dry spell will last through Sunday with high temperatures in
the mid to upper 80s across the lowlands on Saturday and upper 80s
to lower 90s on Sunday, with the mountains ranging in the lower 70s
to mid 80s. These temperatures are above normal for this time of
year. Dew points will also be backing off some starting Saturday
afternoon, allowing for a less oppressive feel as they drop from the
70s into the 60s. Overnight lows will remain around normal across
the lowlands to slightly above in the mountains with low to mid 60s
expected for all each night.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
As of 300 AM Friday...

Monday certainly looks to be the hottest and most humid day next
week at this point in time with highs in the lower to mid 90s across
the lowlands. Southerly flow will resume to usher in more humidity
and moisture with dew point Temperatures looks to remain around
normal or slightly above for the rest of the week. Dew points
in the 70s expected for a few locations across the lowlands.
Temperatures looks to remain around normal or slightly above for
the rest of the week.

Chances for showers and thunderstorms also increase on Monday with a
shortwave and most definitely on Tuesday with a cold front.
Nonetheless, chances for showers and storms remain each
afternoon with diurnal heating, even with models differing
greatly.

&&

.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
As of 645 AM Friday...

A cluster or line segments of thunderstorms are likely to cross
mainly southern portions of the area this afternoon and
evening.

Patchy MVFR stratocumulus will lift and scatter out later
this morning, yielding VFR conditions into this afternoon.

Showers and thunderstorms are most likely across southern sites
later this afternoon and evening, as a convective complex moves
across. A shower or thunderstorm is possible most anywhere
tonight, as a cold front approaches. Any thunderstorm this
afternoon and evening can produce brief IFR conditions and
strong wind gusts.

Patchy valley fog forming again overnight tonight could impact
TAF sites with MVFR to IFR visibility, especially where
thunderstorms hit. MVFR stratocumulus may also form.

Surface flow outside thunderstorms will be light southwest
today and tonight. Moderate west flow aloft this morning will
become light southwest this afternoon, and then light to
moderate west overnight tonight.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SATURDAY...

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Extent of MVFR stratocu may vary this
morning, with IFR stratus briefly possible early. Thunderstorms
this afternoon may develop or arrive sooner than currently
forecast. Development of fog and MVFR stratocu/IFR stratus
overnight tonight 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.

UTC 1HRLY       12   13   14   15   16   17   18   19   20   21   22   23
EDT 1HRLY       08   09   10   11   12   13   14   15   16   17   18   19
CRW CONSISTENCY  M    L    H    H    H    H    H    H    H    H    H    H
HTS CONSISTENCY  M    H    H    H    H    H    H    H    H    M    H    H
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
EKN CONSISTENCY  H    H    M    H    H    H    H    H    H    H    H    H
PKB CONSISTENCY  L    M    H    H    H    H    H    H    H    H    H    H
CKB CONSISTENCY  H    H    H    M    H    H    H    H    H    H    H    H

AFTER 12Z SATURDAY...
IFR in low stratus or fog possible early Saturday morning.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...Heat Advisory until 5 PM EDT this afternoon for WVZ006-013>015-
     025-026.
OH...None.
KY...None.
VA...None.

&&

$$

SYNOPSIS...TRM/LTC
NEAR TERM...TRM/JP
SHORT TERM...LTC
LONG TERM...LTC
AVIATION...TRM