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807
FXUS61 KRLX 261851
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
251 PM EDT Sun May 26 2024

.SYNOPSIS...
Showers and storms through Memorial Day weekend in response to a
cold front. Damaging wind gusts, hail, and locally heavy downpours
will be possible. Remaining unsettled Tuesday and Wednesday.

&&

.NEAR TERM /THROUGH MONDAY/...
-- Changed Discussion --
As of 250 PM Sunday...

Key Points:

 * Bowing line of thunderstorms arriving soon to the western
   flank of the forecast area this afternoon.

 * Strong to severe thunderstorms possible with potential for
   damaging wind gusts, large hail, and brief spin up tornadoes.

 * Heavy downpours associated with convection may produce
   localized flash flooding.

What was a beautiful and quiet morning around the Central
Appalachians has quickly grown active as we await a bowing
convective segment encroaching on eastern Kentucky and Ohio and
the time of writing. This line of storms has had history of
producing very strong winds on the upwards of 60+ mph gusts
throughout the morning and early afternoon upstream in the
Tennessee Valley, with a few spin up tornadoes noted by
neighboring offices currently facing the southern end of this
system. A Severe Thunderstorm Watch is already in place for the
vast majority of the forecast area this afternoon as we monitor
storms dashing across the region.

Mesoanalysis depicts storms have outran the favorable sheared
environment that was present earlier today in western and
central Kentucky, denoting more of a wind threat now, but still
would not rule out quick QLCS tornadoes that become embedded in
the descending notch. Warm and muggy conditions here in our
forecast area will aid in sustaining storms as they travel into
West Virginia and perhaps up into the northeastern mountains.

In addition to the potential for winds, hail, and tornadoes,
there will be the increasing concern for heavy downpours as
convection ventures overhead. With PWATs projected to rise to
around 1.5-1.8 inches today and tall, skinny CAPE profiles
denoted by forecast soundings, it is certainly not out of the
question to observe rainfall rates on the upwards of 1-2 inches
per hour. This would impede on recovering ground conditions from
antecedent rain and lead to flash flooding concerns.

Convective trends this afternoon and evening will be the
catalyst for how overnight activity will fare. Hi-res guidance
for this afternoon suggests a secondary line of showers and
storms forming upstream that will maintain active weather for
the overnight period. This could become primarily outflow driven
and take a southward trajectory away from the Ohio River Valley
tonight, but held onto likely POPs once again crossing the CWA
overnight into early Monday morning. However, this first line of
convection could overwork our environment and impose less of a
severe threat late tonight. Regardless, rain and flooding
concerns stretch into the overnight hours, especially in the
event of training.

Unsettled weather triumphs into Memorial Day as a low pressure
system and its attendant cold front drift further eastward.
While a break in activity seems plausible during the morning
hours Monday, isolated to possibly scattered showers and storms
return to the forecast once more for the afternoon and evening.
Temperatures will be a few degrees cooler on Monday, but dew
points remain well into the 60s, leading to another muggy day
across the area. The cold front will continue eastward progress
through the region at the conclusion of the near term period.

As of 248 AM Sunday...

Key Points:

 * Hot and humid today.
 * Enhanced risk for severe storms NE Kentucky through tonight.
 * Slight risk for severe storms rest of the area, except NE
   mountains through tonight.
 * Slight risk for excessive rainfall over the southern two
   thirds of the area through tonight.

Widespread river valley dense fog will gradually dissipate early
this morning.

Frontal boundary, oriented west to east across our north, lifts
north as a warm front this morning, leaving the area under a warm
sector of an approaching cold front. Winds increase from the
southwest, bringing strong moisture advection with boundary layer
theta-e values exceeding 340K by this afternoon. A mid level
shortwave crosses the area this afternoon, providing upper forcing
to enhance convection.

Local bufkit soundings show a tall/skinny CAPE signature with dry
air at the mid levels by this afternoon. Guidance suggests deep
layered shear will limited over most parts of the area, except
far west across NE KY where values of 50 to 60 knots are
anticipated. These ingredients will allow for strong to severe
updrafts /downdrafts, the strongest; farther west where the best
dynamics will be present. With PWATs increasing from 1.3 to 1.7
inches by this evening, very heavy downpours are likely, some
capable to produce flash flooding. Hi-res CAMs suggest a strong
line of convection arriving to the Tri-state area (OH/KY/WV)
around 3 PM spreading east as some elements weaken. A second
batch of convection is forecasted right behind it, but it seems
to weaken as well as the reach NE KY and portions of the Mid
Ohio valley. However, strong to severe storms may be able to
survive and spread east further into WV with the passing of
another upper level shortwave around midnight as convective
parameters become more active, with deep layered shear
increasing to 55 knots, PWATs around 1.7 inches and CAPE about
1200 J/Kg.

SPC maintains an enhanced risk for severe thunderstorms over NE
KY, a slight risk roughly across the rest of the area, except
for the northern mountains through tonight. Therefore, expecting
scattered to possibly numerous severe storms around the Tri-
State area this afternoon and evening, with damaging gusty wind,
large hail, and the possibility of tornadoes being the main
threats.

WPC has a slight risk for excessive rainfall across the
southern two thirds of the area, and a marginal risk across the
northern third. This translates to the possibility of very heavy
rain and associated flash flooding.

Despite clouds and convection expected, highs will manage to reach
the mid to upper 80s across the lowlands, ranging into the lower 70s
across the higher elevations of our northeast mountains. Lows
tonight will generally be in the 60s.
-- End Changed Discussion --

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 1137 AM Sunday...

Showers and a few isolated thunderstorms will remain possible
Tuesday and Wednesday with shortwave energy flowing around the base
of a 500-mb trough. Areas with the best chance at seeing showers
will be in northern parts of the area and in the mountains. Severe
weather is not anticipated at this time.

For both Tuesday and Wednesday, temperatures will be a bit lower
than recent days with highs only in the 70s in the lowlands and the
upper 60s to 70s in the mountains. Wednesday night might even feel
chilly to some with temperatures dropping into the 40s and lower 50s
for lows.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 1137 AM Sunday...

The long term forecast period looks largely dry with high pressure
building into the region from the west. Temperatures will remain
comfortably cool Thursday and Friday with highs in the 70s for most.
The summer-like warmth will return next weekend as high pressure
slides east and southerly flow returns. There is a slight
chance of showers or thunderstorms Saturday with 500-mb
shortwave energy approaching from the west, but confidence is
low at this time.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --
As of 1234 PM Sunday...

Approaching line of showers and thunderstorms will reach our
western terminals around or just shortly after the 18Z TAF
issuance, then follow a northeasterly trajectory through the
forecast area. This trend continues into tonight, with all
airfields having a high potential to see a strong to possibly
severe thunderstorm pass overhead or near the site. Any storm
that does become severe could yield damaging wind gusts, large
hail, and a quick spin up tornado.

A secondary line of convection scrapes the area late tonight
into the overnight hours. Additional lightning is possible
overnight, with focus gradually becoming more on the heavy
downpours associated with this renewed precipitation. Ceilings
will also lower in the process for the Ohio River Valley and up
the mountains for Monday morning. While gradually improving on
Monday along the higher terrain, MVFR cigs will fester over
southeast Ohio as a frontal boundary is tucked in close quarters
to our airspace. That front is progged to pass through the
region late Monday evening into Tuesday morning. Additional
convection is possible during the second half of the day Monday.

Winds begin out of the southwest today, but could grow breezy to
gusty in response to convection. Low level jet snakes through
the area late tonight, and could promote a few instances of LLWS
around HTS or CRW.

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

FORECAST CONFIDENCE: High.

ALTERNATE SCENARIOS: Timing of thunderstorms and weather
restrictions may vary from forecast.


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       19   20   21   22   23   00   01   02   03   04   05   06
EDT 1HRLY       15   16   17   18   19   20   21   22   23   00   01   02
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    M    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    M    H    H    H    H    H    H

AFTER 18Z MONDAY...
IFR possible at times in showers and storms through the first
half of the week.
-- End Changed Discussion --

&&

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

&&

$$

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