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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRLX 242331
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
731 PM EDT Sun May 24 2020

.SYNOPSIS...
Hazy, very warm, and humid for much of this week as summer-
like upper level ridge builds into the region. Cold front late
week.

&&

.NEAR TERM /THROUGH MONDAY/...
As of 720 PM Sunday...

Made some additional updates to increase PoPs across Mingo/Logan
county this afternoon to reflect nearly stationary robust
upright convection. Also increased cloud cover overnight with
substantial convective debris being generated from an area of
storms across Eastern Kentucky, Southern West Virginia and
Western Virginia.

As of 350 PM Sunday...

Added an isolated shower/thunderstorm mention across portions
of the Middle Ohio Valley for the next couple hours where a few
convective towers are poking up enough to produce measurable
precip. These should wane quickly with loss of heating this
afternoon. Storms drifting toward the Tri-State area may
persist a little further into the evening where a combination of
very weak upper level divergence and weak low level ascent
along the theta-e ridge exists.

As of 202 PM Sunday...

An outflow boundary was pushing south and west of Kanawha
County, resulting in isolated to widely scattered convective
development. Farther east, more significant heavy convection
was occurring along the CWA mountain spine. Convection across
the mountains is likely to continue progressing east during the
afternoon with renewed development of a few more isolated
showers possible in its wake. Across the southern and the
southwest portion of the CWA, convection should start to pop
over the next couple of hours as ConvT values are exceeded and
as the outflow boundary pushes into an area with maximized
diurnal heating and SBCAPES of 2500 to 3000 j/kg. Overall, slow
moving pulse convection should occur with some highly efficient
production likely. This may result in some isolated high water
impacts, but the overall flash flood threat today is low.

Convection should rapidly dissipate by early evening with the
onset of nocturnal cooling. Some debris CI may occur for the
first half of the night, but significant clearing is likely.
Late night fog may occur, with the best chances expected to be
across the NE CWA and a few area river valleys.

H5 ridging is prog to strengthen across the CWA on Memorial
Day. This increase in height fields and associated subsidence
should result in hotter conditions and less coverage of
convection in the afternoon. Still expecting isolated to widely
scattered diurnally driven convection to occur, mainly across
the western CWA where moisture depth is prog to be slightly
greater and height fields the lowest...and also along the
mountains where modest orographic effects may aid in some
development.

Muggy conditions tonight as dewpoints remain high and soils
continue to stay saturated. Very warm to hot on Memorial Day
with little in the way of a breeze across the lower elevations.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 245 PM Sunday...

Upper level ridging begins to break down and succumb to incoming
moisture from the west Tuesday afternoon, but will ultimately
prevail in keeping rain west of the Ohio River. The ridge will
then shift eastward by midweek and allow for a greater
likelihood and spread of precip Wednesday afternoon, approaching
from all quadrants except from the north. Temperatures remain
above normal through the period under the ridge and looks to
remain that way into the long term period.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 245 PM Sunday...

Active weather ramps back up and results in a soaking end to the
work week. Upper level ridge will continue to shift eastward and
make way for a developing low forming in the central US.
Moisture transport and continued warm advection will place the
region in the warm sector of the developing system, which will
pose a better potential for strong to severe storms Friday and
Saturday afternoons. Eventual cold front will cross through for
the start of the weekend with high pressure building in its
wake. Temperatures will rebound behind the frontal passage
Saturday, but beforehand above average temps will be the norm
in the lowlands.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
As of 720 PM Sunday...

Convective debris from storms across E KY, W VA and S WV
producing cigs 100-200 will slow any patchy fog formation
overnight. The one exception will be at EKN with fresh rainfall
and clear skies through the early evening should radiate out
enough for at least some more dense fog. Should largely see any
lingering convective debris clearing by morning and have gone
5-6SM in mist at the other terminals for a couple hours near
daybreak.

Popcorn convection likely again Memorial Day afternoon, but
should see far less coverage than today with minimal morning
activity.

Generally weak SSWrly sfc winds through the period, except more
SErly at KBKW.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z TUESDAY...

FORECAST CONFIDENCE: High.

ALTERNATE SCENARIOS: Fog coverage may vary overnight depending
on timing scattering of convective debris.

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       22   23   00   01   02   03   04   05   06   07   08   09
EDT 1HRLY       18   19   20   21   22   23   00   01   02   03   04   05
CRW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    M    M
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    M    H    M    H
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    M    M
CKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    M    L

AFTER 00Z TUESDAY...
No widespread IFR conditions expected at this time.

&&

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

&&

$$
SYNOPSIS...RH/MEK
NEAR TERM...RH/JP
SHORT TERM...MEK
LONG TERM...MEK
AVIATION...JP