Area Forecast Discussion
Issued by NWS Charleston, WV

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738
FXUS61 KRLX 101044
AFDRLX

Area Forecast Discussion
National Weather Service Charleston WV
644 AM EDT Mon Aug 10 2026

.WHAT HAS CHANGED...
Forecast thinking has sharpened around a multi-day
northwesterly-flow train of convective complexes. The primary
upgrade is coordination with WPC on a Day 2 Moderate Risk of
excessive rainfall across much of southeast Ohio and central
West Virginia.

As of 640 AM Monday...

Updated 12Z aviation discussion.

&&

.KEY MESSAGES...
1.) Substantial flash flooding is possible early Tuesday
through Thursday night across southeast Ohio, central West
Virginia, northeast Kentucky, and the southern coalfields as
repetitive convective complexes move through the region.

2.) Multiple rounds of severe thunderstorms capable of
producing primarily damaging wind gusts are possible this
evening through Wednesday/Thursday evening.

3.) A brief transition to drier and calmer weather is expected
by Friday night into the start of the weekend as upper-level
ridging shifts east and moves the storm track out of the area.

&&

.DISCUSSION...
KEY MESSAGE 1...

The primary meteorological concern through mid to late week is a
train of mesoscale convective systems (MCSs) tracking
southeastward in northwesterly flow aloft around the
northeastern periphery of an amplifying ridge over the middle of
the country. While the individual MCSs are expected to maintain
a fairly progressive forward propagation, repetitive rounds of
convection over the same corridors present a high-impact flash
flooding and river flooding threat.

Precipitable water values across the region will hover between
1.6 and 2.0 inches, representing the 90th to 95th percentile for
mid-August climatology. Confluent low-level westerly flow
intersecting an east-west oriented instability axis will support
hourly rainfall rates exceeding 2 to 4 inches per hour within
deeper convective cores. While the current lush state of summer
vegetation and intervening intervals allow soils to handle
moderate water loads initially, localized extreme rainfall rates
can quickly exceed soil infiltration capacity. Any mesoscale
backbuilding to the northwest or west, or any convective line
orienting east-to-west parallel to steering flow, will produce
prolonged dwell times of extreme rainfall rates, leading to
localized life-threatening flash flooding regardless of
antecedent soil conditions and with pre-moistening soils these
threats will emerge event quicker.

The threat is heightened during overnight hours when flash
flooding is hardest to detect and react to. In coordination with
WPC, a Day 2 Moderate Risk for Excessive Rainfall has been
placed over much of southeast Ohio and central West Virginia for
Tuesday. Given low confidence in the exact spatiotemporal track
of individual convective complexes due to upstream cold pool
evolution and environmental modification, Flash Flood Watch
issuance is deferred for now. However, a Flash Flood Watch
encompassing most or all of the forecast area will almost
certainly become necessary for the Tuesday through Thursday
period. It is important to note that this scenario is not
guaranteed to be widespread or even occur at all, but this setup
does leave the potential open to locally extreme flash flooding
impacts.

Multi-day cumulative precipitation totals of 3 to 6 inches
across larger river basins will drive significant rises,
which could lead to river flooding, especially downstream of any
localized extreme rainfall totals.

The key takeaway is: Residents in hollows, floodplains, and low-
lying terrain should have multiple ways to receive warnings
and have a plan of action to move to higher ground this week if
conditions warrant.

KEY MESSAGE 2...

A lesser but still substantial hazard involves severe weather
associated with the daily convective complexes through Wednesday
evening. The primary severe hazard will be damaging straight-
line wind gusts driven by consolidated MCS cold pools, though
bowing line segments and mesoscale boundary interactions will
also support an embedded tornado risk. The conditional threat
for more semi-discrete or discrete supercellular convection
capable of all severe modes will be highest during peak heating
late this afternoon (although this may remain north of us and
already be congealed by the time it arrives) and again Wednesday
afternoon and evening.

Forecast soundings across the region display strong
thermodynamic support, with MLCAPE reaching 2000 to 3000J/kg
and DCAPE values between 800 and 1200J/kg. Deep-layer 0-6km bulk
shear of 35 to 45KTs and 0-3km SRH near 100 to 200m2/s2 support
organized convective modes given discrete convection.

In Appalachia and steep terrain, full tree canopy foliage
combined with rapidly saturating topsoil lowers severe wind
damage thresholds significantly. Sub-severe wind gusts of 40 to
50 mph, especially when sustained over several minutes typical
within cold pool driven gusts corridors, can easily uproot
trees and knock down power lines.

SPC maintains a Slight Risk for severe storms daily through
Wednesday. An upgrade to risk levels may be warranted,
especially on Tuesday/Wednesday as confidence increases.

For today, an ongoing MCS over Illinois and Indiana will weaken
as it approaches western counties late this morning. Resulting
morning cloud cover and stabilization across northern counties
may limit convective coverage there this afternoon (displacing
convective initiation farther north). This developing complex
could drop south overnight bringing forth the first round of
severe storms.

KEY MESSAGE 3...

A temporary break in this persistent fire hose of MCS pattern
is possible by Friday night and the start of the weekend. Upper-
level ridging over the south-central states is forecast to
shift slightly eastward, pushing the primary shortwave track and
moisture plume east of the central Appalachians. This
transition will yield a trend toward drier and calmer conditions
for Friday night through Saturday.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
Remnant cloudiness associated with former convective activity
will overspread the region from the northwest this morning.
Could see some revitalization of this activity this afternoon
and have included VCTS at the western terminals. Additional
storms may fire late this afternoon into evening across the
north and progress south overnight. IFR conditions are possible
in any convection.

Outside of convection, prevailing VFR conditions will dominate
with southwest winds around 5 to 10KTs

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

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Afternoon convection could see less
coverage than advertised, overnight activity could be more
substantial than advertised.

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       10   11   12   13   14   15   16   17   18   19   20   21
EDT 1HRLY       06   07   08   09   10   11   12   13   14   15   16   17
CRW CONSISTENCY  M    M    L    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    M    H    H    H    H    H    H    H    H    H
EKN CONSISTENCY  M    L    L    H    H    H    H    H    H    H    H    H
PKB CONSISTENCY  M    L    H    H    H    M    H    H    H    H    H    H
CKB CONSISTENCY  L    L    H    H    H    H    H    H    H    H    H    H

AFTER 12Z TUESDAY...
Tuesday through Friday, additional convective complexes favor
daily chances of showers and thunderstorms with MVFR or IFR in
heavy rain. Morning valley fog or low stratus may return after
wetting rains, especially at EKN and other sheltered sites.

&&

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

&&

$$

DISCUSSION...JP
AVIATION...JP