Special Weather Statement, NWS Charleston, WV

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
1017 AM EDT Sat Jul 17 2021

.SYNOPSIS...
A cold front crosses tonight into Sunday. High pressure crosses
early next week. A weak disturbance will affect the area by
midweek, followed by another high to end the work week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1015 AM Saturday...

Slightly adjusted chances for showers for the next few hours as
it has been off to a slightly slower start than initially
thinking. Showers are developing along the western portion of
the area this hour. Showers and thunderstorms are then expected
to increase in coverage over the next few hours ahead of the
front, becoming more widespread by the afternoon.

The SPC has expanded the marginal risk for severe weather to
the west/southwest from the previous outlook, now reaching along
central WV and eastward. The main threats expected with any
storms continues to be gusty to strong winds and heavy
downpours.

As of 635 AM Saturday...

Most of the area early this morning was in the warm sector of a
low pressure center tracking north of the area today. Showers,
and a few thunderstorms, formed along the warm front in the
mountains early this morning, while showers ahead of the cold
front were slowly encroaching upon the middle Ohio valley from
the west.

As of 430 AM Saturday...

A surface cold front approaches from the northwest today, and
then crosses tonight, with its associated upper level short
wave trough following close behind. This spells a rapid uptick
in showers and thunderstorms generally from west to east this
morning, leading to widespread coverage this afternoon into
tonight.

With this rapid uptick limiting heating, and a prefrontal lee
trough forming east of the central Appalchians today, surface
based CAPE will be limited to 1-1.5 KJ/kg. SPC has allowed a
marginal risk for severe weather as far west as the northern WV
mountains, as a modest bulk shear axis crosses there this
afternoon.

High precipitation coverage, and PW values up around two inches
supports heavy downpours, which could lead to flash flooding
where they repeat, this afternoon into tonight. Recent dry
weather and summer foliage should limit the potential for
excessive rainfall to a marginal risk.

As the front crosses, showers and thunderstorms taper off from
northwest to southeast through the middle Ohio Valley late
today and tonight, and into the central Appalachians overnight
into early Sunday morning. This will be followed by low clouds
and areas of fog, and any partial clearing over the middle Ohio
Valley would make dense fog more likely there.

Central guidance temperatures reflect early highs today, which
should fall just short of normal, and then near to below normal
lows tonight, lowest to the north and west.

&&

.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
As of 300 AM Saturday...

An upper level low will drag its frontal boundary through the
area on Sunday promoting higher chances for showers and storms
ahead of the front. This will mainly be confined to the higher
elevations although just a few isolated lingering showers could
exist for the lowlands through midday due to drier air expected
to filter in and suppress convection with the help of northerly
flow. Had to taper off POPs earlier than what guidance
suggested mainly due to the way models were pushing the front
out sooner than previous runs. Therefore, the majority of
modifications were to Sunday evening/night with adjusting
categorical and likely POPs down to chances and speeding up
frontal passage. Not expecting any severe type storms and most
of the area has relatively low PWAT values except for maybe the
far southern portion of the CWA, who will just catch a sliver of
a marginal threat for excessive rainfall ahead of the front,
until frontal passage Sunday evening.

Models consensus is strongly in favor of settled weather for
Monday and Tuesday although the EURO/SREF hold on to diurnal
chances for mainly the higher elevations. Did however sort of
accept POPs from guidance for both days, but trimmed some down
to just slight chances for Monday and removed slight chances
completely from Tuesday as the area should remain relatively
dry. Temperatures will hover around a degree or two below the
climatological norm through this period.

&&

.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
As of 300 AM Saturday...

Long rang models are in fairly good agreement with a disturbance
traversing through the area from the north on Wednesday. Raised
POPs slightly from guidance since models are picking up on this
solution better than the previous day. Thursday looks to be a
good fair weather day although one cannot rule out a diurnal
pop up shower/storm. However, guidance had no POPs, so decided
to keep the status quo since confidence is just not there at
this time. On Friday, models are still all over the place so
decided to make some minor changes to central guidance which
equated to slight/chance POPs/storms for Friday into Saturday.
Temperatures will top off at the climatological norm threshold
through this period.

&&

.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
As of 635 AM Saturday...

A cold front moving into the area brings active weather this
period, with showers and thunderstorms developing / moving in
from the west today, followed by a more general deterioration
in flight conditions tonight.

Showers and thunderstorms will develop and move in from the west
during the morning and midday hours today, with enough coverage
to explicitly code MVFR conditions in thunderstorms this
afternoon, and IFR or worse conditions are possible in direct
hits of heavier storms.

As showers and thunderstorm move east with the cold front tonight,
there will be a more general lowering of visibility and
ceilings especially in the wake of the front, with IFR ceilings
and possibly visibility setting in overnight tonight.

Light southwest surface flow can become a bit gusty prior to and
with the onset of rain today, with stronger, veered gusts
possible in thunderstorms, and then shift to light northwest
behind the cold front tonight, before becoming light and
variable overnight tonight. Light to moderate southwest flow
aloft today will become light to moderate west to northwest
behind the front aloft tonight.

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

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Deteriorating conditions today into tonight
may vary and fluctuate. Timing and extent of dense fog and
stratus is likely to vary overnight tonight.

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       12   13   14   15   16   17   18   19   20   21   22   23
EDT 1HRLY       08   09   10   11   12   13   14   15   16   17   18   19
CRW CONSISTENCY  H    H    H    H    H    H    H    M    M    M    M    M
HTS CONSISTENCY  H    H    M    H    H    H    M    M    H    M    M    H
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    M    M    M
EKN CONSISTENCY  M    H    H    H    H    H    H    H    H    M    M    M
PKB CONSISTENCY  H    H    M    H    H    H    H    H    M    H    H    M
CKB CONSISTENCY  H    H    H    H    H    H    H    H    M    M    M    M

AFTER 12Z SUNDAY...
IFR stratus and fog possible with a stalling front early Sunday
morning. Associated rain may also reduce visibilities to IFR
early south. Early morning valley fog possible early next week.

&&

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

&&

SYNOPSIS...TRM/JZ
NEAR TERM...TRM/CG
SHORT TERM...JZ
LONG TERM...JZ
AVIATION...TRM

Hazardous Weather Outlook
National Weather Service Charleston WV
339 AM EDT Sat Jul 17 2021

WVZ040-523>526-180745-
Barbour-Northwest Pocahontas-Southeast Pocahontas-Northwest Randolph-
Southeast Randolph-
339 AM EDT Sat Jul 17 2021

This Hazardous Weather Outlook is for portions of northeast West
Virginia and northern West Virginia.

.DAY ONE...Today and Tonight.

Thunderstorms are possible today ahead of a frontal boundary. There
is a marginal threat for severe storms and a marginal threat for
excessive rainfall. The strongest storms will have the potential to
produce strong winds, and heavy downpours which may lead to isolated
flash flooding.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions by calling the toll-free spotter hotline, or by other
methods detailed at www.weather.gov/rlx/reports.

KYZ101>103-105-OHZ066-067-075-076-083>087-VAZ003-004-WVZ005>011-
013>020-024>034-039-515>522-180745-
Greenup-Carter-Boyd-Lawrence KY-Perry-Morgan-Athens-Washington-
Jackson OH-Vinton-Meigs-Gallia-Lawrence OH-Dickenson-Buchanan-Wayne-
Cabell-Mason-Jackson WV-Wood-Pleasants-Tyler-Lincoln-Putnam-Kanawha-
Roane-Wirt-Calhoun-Ritchie-Doddridge-Mingo-Logan-Boone-Clay-Braxton-
Gilmer-Lewis-Harrison-Taylor-McDowell-Wyoming-Upshur-
Northwest Raleigh-Southeast Raleigh-Northwest Fayette-
Southeast Fayette-Northwest Nicholas-Southeast Nicholas-
Northwest Webster-Southeast Webster-
339 AM EDT Sat Jul 17 2021

This Hazardous Weather Outlook is for northeast Kentucky, southeast
Ohio, southwest Virginia and much of West Virginia.

.DAY ONE...Today and Tonight.

Thunderstorms are possible today ahead of a frontal boundary. There
is a marginal threat for excessive rainfall. The strongest storms
will have the potential to produce strong winds, and heavy downpours
which may lead to isolated flash flooding.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions by calling the toll-free spotter hotline, or by other
methods detailed at www.weather.gov/rlx/reports.

Special Weather Statement
National Weather Service Charleston WV
1214 PM EDT Sat Jul 17 2021

OHZ087-WVZ006-007-013>015-171700-
Lawrence-Mason-Kanawha-Lincoln-Cabell-Putnam-
1214 PM EDT Sat Jul 17 2021

...A STRONG THUNDERSTORM WILL AFFECT SOUTHEASTERN LAWRENCE...
SOUTHWESTERN MASON...CABELL...WEST CENTRAL KANAWHA...PUTNAM AND NORTH
CENTRAL LINCOLN COUNTIES...

At 1214 PM EDT, a strong thunderstorm was located over Ona, or 7
miles east of Proctorville, moving northeast at 30 mph.

Winds in excess of 40 mph are possible with this storm.

Locations impacted include...
Nitro, Winfield, St. Albans, Hurricane, Barboursville, Milton,
Eleanor, Buffalo, Poca, Ona, Culloden, Teays Valley, Cross Lanes,
Bancroft, Athalia, Salt Rock, Grimms Landing, Pea Ridge, Green Bottom
and Fraziers Bottom.

This includes Interstate 64 in West Virginia between mile markers 15
and 49.

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

LAT...LON 3859 8223 3859 8219 3862 8217 3873 8194
      3839 8176 3831 8228 3851 8240
TIME...MOT...LOC 1614Z 242DEG 28KT 3843 8225

ABE