Flash Flood Warning 169, NWS Charleston, WV

Area Forecast Discussion
National Weather Service Charleston WV
153 PM EDT Mon Aug 17 2026

.WHAT HAS CHANGED...
Aviation discussion updated at 0930Z

In coordination with the Jackson KY forecast office, the Flash
Flood Watch has been expanded to cover our remaining counties
in southern West Virginia and southwest Virginia. Convective-
allowing models show the potential for up to 2 inches of
new rainfall today in these areas, which may exceed flash flood
guidance.

&&

.KEY MESSAGES...
1.) Heavy rainfall may lead to additional flash flooding and
tree damage across the region, especially the southern
coalfields and southwest Virginia, through 2 AM Tuesday.

2.) Widespread low stratus and dense valley fog will build
overnight tonight into Tuesday morning across much of the
region, creating low visibility for the morning commute Tuesday.

3.) A temporary dry break is expected Tuesday through early
Wednesday before another cold front brings renewed shower and
thunderstorm chances with flash flood potential Wednesday night
through Thursday.

&&

.DISCUSSION...
KEY MESSAGE 1...

Destabilization is under way across the region in the wake of a
decaying morning convective complex, with the most robust
clearing located across southern areas. The strongest
convective cores will graze portions of southwest Virginia and
the southern coalfields where SPC has added a slight risk of
severe storms. Additional scattered to numerous showers and
thunderstorms are already developing along a slow-moving
surface cold front pressing southeastward across the Middle Ohio
Valley.

The thermodynamic environment remains exceptionally moist,
characterized by precipitable water values approaching 2.0
inches, which sits well above seasonal climatology. Soundings
display long, skinny instability profiles with Mixed-Layer CAPE
reaching 800 to 1200 J/kg, up to 1500 J/kg across southern
counties. These soundings feature deep warm cloud depths
exceeding 12000 feet, supporting highly efficient warm rain
production with rainfall rates of 1 to 2 inches per hour. Flow
at H700 around 30 to 35KTs out of the west will keep individual
convective cores moving at a modest pace. However, low-level
convergence along the cold front as it sinks slowly to the
southeast runs nearly parallel to the mid-level flow, which may
promote cell training over the same drainages.

Deep-layer bulk shear of 25 to 30KT will favor a predominantly
multicellular storm mode. Low-level hodographs show modest
curvature, yielding effective storm-relative helicity of 70 to
100 m2/s2. This shear profile could foster brief updraft
rotation in any semi-discrete cells, maintaining a low, though
non-zero, threat for a brief tornado. While the primary severe
wind potential remains concentrated along our southern border
where instability is maximized, antecedent saturated ground
conditions mean that even sub-severe wind gusts of 35 to 45 mph
can uproot exposed trees.

Given severely compromised soils from repeated heavy rainfall
over the preceding days, 3 hour flash flood guidance is
generally between 1.0 and 1.5 inches across much of the forecast
area. High precipitation rates will result in rapid runoff into
small streams. A Flash Flood Watch remains active through 2 AM
EDT Tuesday.

KEY MESSAGE 2...

In the wake of the cold frontal passage late tonight, surface
winds will diminish to 5 mph or less under weak northwesterly
flow. While we should maintain at least some mid-level cloud
cover, will likely see surface temperatures falling to
saturation by early Tuesday morning. Widespread low stratus and
fog is expected expected to form over much of the area heading
into Tuesday morning which could impact the morning commute.

KEY MESSAGE 3...

A brief period of dry weather will take hold Tuesday afternoon
through most of Wednesday as high pressure builds across the
Central Appalachians and column moisture decreases behind the
cold front. Precipitable water values drop to around 1.0 to 1.2
inches on Tuesday, allowing small streams and creeks an
opportunity to recede. However, subsurface soil moisture will
remain nearly saturated, leaving infiltration capacity severely
degraded.

Atmospheric moisture will pool northward again late Wednesday
into Wednesday night ahead of the next upper-level shortwave
trough and cold front. Precipitable water values rise back
toward 1.8 inches by Thursday morning. Upper-level dynamics will
strengthen as the right rear quadrant of an H200 jet streak
positions over the Middle Ohio Valley, providing broad synoptic
scale ascent. With modest diurnal destabilization expected
Thursday afternoon, scattered to numerous showers and
thunderstorms will redevelop along the boundary. High
instantaneous rainfall rates falling on saturated soils will
present a renewed flash flood risk, supporting the Weather
Prediction Center Marginal Risk of Excessive Rainfall for
Thursday.

The broad synoptic pattern through the late week and upcoming
weekend will be dominated by strong mid-level ridging over the
western United States and longwave troughing centered over the
eastern tier. This configuration will keep the Central
Appalachians in northwest flow aloft, directing periodic
shortwaves and secondary cold fronts through the region every
couple of days.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
Scattered to numerous showers and thunderstorms will continue to
develop ahead of a cold front this afternoon and early evening.
Outside of convection, prevailing ceiling heights will hover
between 2500 and 4000 feet  Direct thunderstorm impacts will be
brief, producing temporary IFR visibility down to 1 to 2SM.

As the cold front moves southeast of the region after 02Z
Tuesday, surface winds will diminish to 5KTs or less from the
northwest. Saturated surface conditions and light upslope flow
will foster widespread low stratus and fog development heading
into Tuesday morning. Widespread IFR to LIFR ceilings below 500
feet AGL and visibilities of 1/4 to 1 SM are expected across
most terminals. Expect gradual improvement through 15Z

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

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: The timing and spatial extent of fog
overnight tonight may vary depending on extent of partial
clearing behind the cold front.  Thunderstorm direct hits at
any single terminal this afternoon may produce 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       17   18   19   20   21   22   23   00   01   02   03   04
EDT 1HRLY       13   14   15   16   17   18   19   20   21   22   23   00
CRW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    L    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    M    H    M    M    M    M    H    H    H    H    L
PKB CONSISTENCY  H    H    H    M    H    H    H    H    H    H    M    H
CKB CONSISTENCY  H    H    H    H    M    H    M    H    H    H    H    H

AFTER 18Z TUESDAY...
IFR valley fog possible Wednesday morning.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...Flood Watch through late tonight for WVZ005>011-013>020-
     024>034-039-040-515>526.
OH...Flood Watch through late tonight for OHZ066-067-075-076-
     083>087.
KY...Flood Watch through late tonight for KYZ101>103-105.
VA...Flood Watch through late tonight for VAZ003-004.

&&

DISCUSSION...JP
AVIATION...JP

Preliminary Local Storm Report
National Weather Service Charleston WV
919 AM EDT Mon Aug 17 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0955 PM     Flash Flood      5 N Gauley Bridge       38.24N 81.19W
08/16/2026                   Fayette            WV   Dept of Highways

            High Water in the 35000 block of Twenty Mile
            Creek Rd.

&&

JP

Preliminary Local Storm Report
National Weather Service Charleston WV
1052 AM EDT Mon Aug 17 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1150 PM     Rain             2 NE Weston             39.07N 80.44W
08/16/2026  M2.30 Inch       Lewis              WV   Public

            Reported by Trained Spotter. 6.48 inches
            since August 1, 2026.

&&

Preliminary Local Storm Report
National Weather Service Charleston WV
1053 AM EDT Mon Aug 17 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0711 PM     Rain             1 SE Somerset           39.80N 82.29W
08/16/2026  M1.50 Inch       Perry              OH   Trained Spotter

            Fell between 6:55 PM to 7:10 PM.

&&

Preliminary Local Storm Report
National Weather Service Charleston WV
1205 PM EDT Mon Aug 17 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0851 PM     Flash Flood      3 NNE Cross Lanes       38.47N 81.75W
08/16/2026                   Putnam             WV   911 Call Center

            Lick Branch road is covered with water and
            completely washed out and unpassable.

&&

Preliminary Local Storm Report
National Weather Service Charleston WV
124 PM EDT Mon Aug 17 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0123 PM     Rain             5 E Amesville           39.39N 81.87W
08/17/2026  M1.35 Inch       Athens             OH   Cocorahs

            Measured between 12:45pm EDT and 1:15 PM
            EDT.

&&

Special Weather Statement
National Weather Service Charleston WV
142 PM EDT Mon Aug 17 2026

VAZ003-004-171830-
Dickenson VA-Buchanan VA-
142 PM EDT Mon Aug 17 2026

...A STRONG THUNDERSTORM WILL IMPACT DICKENSON AND SOUTHWESTERN
BUCHANAN COUNTIES THROUGH 230 PM EDT...

At 142 PM EDT, Doppler radar was tracking a strong thunderstorm over
Ashcamp, or 7 miles west of John Flannagan Lake, moving east at 35
mph.

HAZARD...Wind gusts up to 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Clintwood, Grundy, Haysi, Breaks Interstate, Davenport, John
Flannagan Lake, Big Rock, Trammel, Clinchco, Stacy, Nora, Vansant,
and McClure.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3697 8237 3702 8248 3713 8255 3720 8255
      3724 8245 3727 8235 3728 8234 3728 8232
      3736 8222 3732 8195 3704 8206 3704 8208
      3705 8210 3704 8212 3704 8217 3699 8226
      3700 8227 3700 8229 3696 8235
TIME...MOT...LOC 1742Z 281DEG 29KT 3726 8247

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

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