405
FXUS61 KRLX 231815
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
215 PM EDT Sun Jun 23 2024

.SYNOPSIS...
A cold front brings showers and thunderstorms into this evening,
with the front crossing tonight. More seasonable air can be
expected behind the front on Monday. Heating up again midweek.

&&

.NEAR TERM /THROUGH MONDAY/...
As of 215 PM Sunday...

After an initial band of showers fell apart as it entered the
area this morning, a new band of showers fired up just west of,
and slicing into northwest portions of, the forecast area early
this afternoon, ahead of a cold front and beneath a broad,
loosely defined mid level short wave trough.

While there is limited opportunity for surface heating due to
cloud cover, temperatures were off to a high start this morning,
and were already at or near convective temperatures, in the mid
to upper 80s, across much of the middle Ohio valley. SPC
analysis showed modest CAPE of under a KJ/kg over much of the
forecast area, but as high as 1.5 KJ/kg along the western
flank, and 2 KJ/kg just upstream, where the convection was
starting to fire up.

This and deep layer bulk shear to 30 kts or so should be just
enough for strong to marginally severe thunderstorm wind gusts,
especially in clusters or short line segments. SPC has
maintained the slight risk of severe thunderstorms for the
middle Ohio Valley, with a marginal risk elsewhere.

While rainfall rates have not been high at all yet, PW values in
the 1.75 to 2 inch range should lead to heavy downpours as
storms intensify this afternoon. WPC continues the marginal risk
for locally excessive rainfall for the area.

Showers and thunderstorms will gradually decrease in intensity
and coverage as they move east across the mountains tonight.
Once the cold front crosses, low clouds may form, mainly in and
near the mountains, but there should be enough gradient low
level flow to keep fog formation limited, and the clouds will
mix into an afternoon cumulus field atop the deepening mixing
layer on Monday.

After a warm evening ahead of the front, save for wet-bulb
cooling, lows Monday morning will be perceptibly lower across
northwest portions of the forecast area, and slightly lower
southeast, compared with this notably warm morning. Monday
brings relief from the heat with highs down around normal.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 230 AM Sunday...

Showers and a few lingering thunderstorms will be tapering off in
the mountains by daybreak on Monday as the cold front pushes
eastward. Only a slight chance for some showers will remain across
the mountains of southern West Virginia and southwestern Virginia.

A secondary cold front with high pressure hot on its heels will then
move through during the morning to reinforce NW`rly flow, drier air
and near normal to slightly below temperatures. The lowlands will
finally see temperatures in the low to mid 80s with afternoon RH
values in the 40s to low 50s. The mountains will range anywhere from
the upper 60s across the highest elevations to around 80 for the
lower elevations and mountain valleys.

With high pressure in place to decouple the region, cool and
comfortable lows are expected Monday night with 50s and low 60s for
the lowlands; 50s in the mountains. Patchy to dense fog will likely
form in the river valleys overnight.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
As of 1148 AM Sunday...

Frontal boundary and upper trough will move east of the area late
Wednesday night or early Thursday, with high pressure building into
the region behind it. This should usher in a brief period of cooler
and drier weather for Thursday. By Friday into the weekend, heat
returns, as southerly flow increases out ahead of the next
system, which will move into the area over the weekend, with
additional rounds of showers and storms. A bit early to say for
sure, but heat headlines may be needed during this time period.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
As of 215 PM Sunday...

Some of the showers developing just west of the area ahead of a
cold front early this afternoon will grow into thunderstorms
that could be strong and heavy as the cross the area later this
afternoon. The best chance for a strong, heavy thunderstorm
will be 20-24Z and mainly over the middle Ohio Valley, versus
the central Appalchians.

Showers and thunderstorms should decrease in strength and
coverage tonight. MVFR stratocu is likely to settle in east of
the Ohio River overnight, and may lower to IFR in the mountains
before dawn Monday, before lifting and breaking up into a
cumulus field later Monday morning. Visibility may lower to MVFR
in and near the mountains toward dawn Monday, before improving
after sunrise.

Gusty southwest surface flow outside thunderstorms this
afternoon will become light west behind the cold front tonight,
and then light northwest on Monday. Light to moderate southwest
flow aloft this afternoon will become light to moderate
northwest behind the front aloft tonight, and then light north
to northwest on Monday.

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

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Timing and intensity of showers and
thunderstorms could vary, and amendments may be needed for brief
IFR conditions.

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       15   16   17   18   19   20   21   22   23   00   01   02
EDT 1HRLY       11   12   13   14   15   16   17   18   19   20   21   22
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    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    M

AFTER 18Z MONDAY...
IFR possible in fog overnight Monday night into early Tuesday
morning.

&&

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

&&

$$

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