296
FXUS61 KRLX 091822
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
222 PM EDT Thu May 9 2024

.SYNOPSIS...
A cold front will bring additional showers and storms this
afternoon and evening, with some storms becoming strong to
severe, before promoting cooler weather Friday and the weekend.

&&

.NEAR TERM /THROUGH FRIDAY/...
As of 220 PM Friday...

Showers and thunderstorms are likely to fire up this afternoon,
as west to southwest low level flow increases ahead of an
approaching low pressure center and cold front. This will begin
with isolated to scattered activity this afternoon, followed by
a segmented line of convection drifting southeastward this
evening into tonight.

Clouds were limiting heating across much of the middle Ohio
Valley, versus areas nearer and in the mountains. With the
opposite pattern in terms of bulk shear, near 60 kts west but
down around 40 kts east integrated 0-6 km, overall severe
potential is marginal. Also, modest low level storm relative
helicity peaking in the 150-200 m2/s2 range will also support
some rotation in more organized cells, like within any line
segments later on.

Pockets of one hour flash flood guidance values of an inch or
less, particularly over the middle Ohio Valley, make such areas
vulnerable to excessive runoff from any heavier thunderstorm,
but vegetation nearing full growth has proven to be a mitigating
factor this week.

Cooler air and low clouds roll in behind the cold front tonight,
and Friday will be a noticeably different day with the low
overcast in place. Showers are possible in the afternoon as a
mid-upper level short wave trough crosses, but instability, if
any, will be limited.

After one last warm afternoon for a few days, central guidance
reflects cooling from northwest to southeast behind the cold
front tonight, and a noticeably cooler day on Friday with lower
60s most of the afternoon across the lowlands, actually below
normal for this time of year.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
As of 230 AM Thursday...

Most of Friday should be unsettled with very little chances of
diurnal thunderstorm potential although we cannot rule them out.
An upper level trough will be the culprit for Friday. Going
into Saturday there will be a break during the morning as
a surface ridge builds in after the aforementioned trough moves
east. But by the afternoon, chances of shower and storm
potential will rise across the entire area as a surface low with
upper level support moves into the region. This feature will be
forecast to graze the northern periphery of our CWA.

Relatively quiet weather anticipated for Sunday as surface high
pressure and upper level ridging builds in and will only allow
for the northeast mountains to endure chances for shower and
storm activity mainly for the afternoon and evening. The rest of
Sunday will be dry area-wide and going into the next period.
Temperatures will remain cooler than normal through Sunday.

&&

.LONG TERM /MONDAY THROUGH WEDNESDAY/...
As of 230 AM Thursday...

For Monday, expect dry conditions into the afternoon although
the rest of the day will have shower chances with little in the
way of any probability for thunderstorms. Another surface low
with upper level support is forecast to approach the area late
Monday keeping chances for shower activity through the rest of
this period along with daily diurnal chances for thunderstorm
activity. This period will also have a warming trend to get the
area back up to around seasonable temperatures, maybe even
slightly above, starting Monday and continuing through midweek.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
As of 220 PM Thursday...

Stratocumulus has scattered out or lifted out of MVFR for the
most part, although brief MVFR ceilings are still possible this
afternoon.

Showers and thunderstorms are likely to fire up this
afternoon, ahead of a low pressure system and cold front,
already producing scattered showers in east-central Ohio early
this afternoon. MVFR to briefly IFR conditions can be expected
directly beneath any thunderstorm, with gusty winds also
possible in and near the storms.

Showers and thunderstorms will diminish after sunset, but onset
and ending timing will generally be earliest northwest /PKB/
and latest southeast /BKW/, as the low pressure system and cold
front progress southeastward through the area tonight.

Stratocu will lower to MVFR and then even IFR behind the cold
front overnight tonight, with MVFR ceilings persisting through
Friday morning. BKW may not quite lower to IFR until the end of
the TAF period, 18Z Friday. There may also be MVFR visibility in
mist/drizzle overnight into Friday morning, possibly lowering to
IFR at times.

Light southwest flow, albeit with the occasional gust here and
there, ahead of the cold front this afternoon will become west
to northwest behind it tonight, and become a bit gusty at least
at BKW by dawn Friday. Moderate west to southwest flow ahead of
the front this afternoon will become moderate west to northwest
behind it tonight, and then light northwest on Friday.

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

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Timing of ceiling and visibility restrictions
may vary from forecast. Winds will fluctuate.

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       18   19   20   21   22   23   00   01   02   03   04   05
EDT 1HRLY       14   15   16   17   18   19   20   21   22   23   00   01
CRW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
HTS CONSISTENCY  M    H    H    H    H    H    H    H    H    H    H    M
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
EKN CONSISTENCY  M    M    H    H    H    M    M    H    H    H    M    H
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
CKB CONSISTENCY  M    M    M    H    H    H    H    H    H    H    H    H

AFTER 18Z FRIDAY...
Lingering IFR conditions behind the cold front remain possible
along the mountains Friday afternoon.

&&

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

&&

$$

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