Alert archive / West Virginia / Tornado Watches in 2014

Tornado Watch 451

July 27, 201419 counties in Virginia; 38 counties in West Virginia

The Storm Prediction Center issued this tornado watch at Jul 27, 2014, 9:28 PM EDT for 19 counties in Virginia; 38 counties in West Virginia. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued: Jul 27, 2014, 9:28 PM EDT (01:28 UTC)
Expired: Jul 28, 2014, 1:05 AM EDT
In force: 4 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2 in
Strongest gust expected: 60 kt

All 57 counties

Albemarle County, VA, Alleghany County, VA, Augusta County, VA, Bath County, VA, City of Buena Vista, VA, City of Charlottesville, VA, City of Covington, VA, City of Harrisonburg, VA, City of Lexington, VA, City of Staunton, VA, City of Waynesboro, VA, Greene County, VA, Highland County, VA, Madison County, VA, Nelson County, VA, Page County, VA, Rockbridge County, VA, Rockingham County, VA, Tazewell County, VA, Barbour County, WV, Boone County, WV, Braxton County, WV, Cabell County, WV, Calhoun County, WV, Clay County, WV, Doddridge County, WV, Fayette County, WV, Gilmer County, WV, Greenbrier County, WV, Jackson County, WV, Kanawha County, WV, Lewis County, WV, Lincoln County, WV, Logan County, WV, Mason County, WV, McDowell County, WV, Mercer County, WV, Mingo County, WV, Monroe County, WV, Nicholas County, WV, Pendleton County, WV, Pleasants County, WV, Pocahontas County, WV, Putnam County, WV, Raleigh County, WV, Randolph County, WV, Ritchie County, WV, Roane County, WV, Summers County, WV, Tucker County, WV, Tyler County, WV, Upshur County, WV, Wayne County, WV, Webster County, WV, Wirt County, WV, Wood County, WV, Wyoming County, WV

The radar

The Charleston,WV radar (KRLX), 90 km from the middle of the area, began a volume at 01:30 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes: 40%
One or more EF2 to EF5 tornadoes: 20%
Ten or more severe wind reports: 30%
One or more gusts of 65 knots or more: 10%
Ten or more severe hail reports: 30%
One or more hailstones of 2 inches or more: 30%
Six or more combined severe hail and wind reports: 60%

Warnings issued inside it

3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

Issued	Product	Office	Counties	Lasted
Jul 27, 9:43 PM EDT	Severe Thunderstorm Warning	LWX	Grant, Hardy, Pendleton	62 min
Jul 27, 9:52 PM EDT	Severe Thunderstorm Warning	LWX	Page, Rappahannock, Shenandoah, Warren	38 min
Jul 27, 10:06 PM EDT	Severe Thunderstorm Warning	RLX	Kanawha	24 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Roanoke, VA (KRNK), launched 00:00Z, 1.5 hours before the alert went out and 156 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 369 J/kg
Mixed-layer CIN: -178 J/kg
Mixed-layer LCL: 1196 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 252 m²/s²
0-3 km storm-relative helicity: 344 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 8.7

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

476 
WWUS20 KWNS 280128
SEL1  
SPC WW 280128
OHZ000-VAZ000-WVZ000-280700-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 451
NWS STORM PREDICTION CENTER NORMAN OK
930 PM EDT SUN JUL 27 2014

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF 
  SOUTHEASTERN OHIO
  NORTHWESTERN AND WESTERN VIRGINIA
  WEST VIRGINIA

* EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING FROM 930 PM
  UNTIL 300 AM EDT.

* PRIMARY THREATS INCLUDE...
  A COUPLE TORNADOES POSSIBLE
  ISOLATED VERY LARGE HAIL EVENTS TO 2 INCHES IN DIAMETER POSSIBLE
  ISOLATED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 110 STATUTE
MILES EAST AND WEST OF A LINE FROM 20 MILES EAST SOUTHEAST OF
BECKLEY WEST VIRGINIA TO 20 MILES NORTHEAST OF ELKINS WEST
VIRGINIA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 448...WW 449...WW 450...

DISCUSSION...SVR POTENTIAL...INCLUDING RISK FOR A FEW
SUPERCELLS/TORNADOES...CONTINUES THROUGH REMAINDER EVENING WITH
FAVORABLE COMBINATION OF CAPE/SHEAR FOR ANY RELATIVELY DISCRETE
TSTMS ALONG/AHEAD OF COLD FRONT.  OTHERWISE...SPORADIC LARGE HAIL
AND DAMAGING GUSTS ARE POSSIBLE.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 27030.


...EDWARDS

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 27, 8:00 PM EDT	Tornado Watch	SPC	Adair, Bath, Bell, Bourbon, Boyle, Breathitt and 44 more	5 hr
Jul 27, 9:39 PM EDT	Mesoscale Discussion	SPC	Frederick	66 min
Jul 27, 11:28 PM EDT	Mesoscale Discussion	SPC	Amelia, Appomattox, Brunswick, Buckingham, Campbell, Caroline and 48 more	2 hr
Jul 27, 8:49 PM EDT	Mesoscale Discussion	SPC	Brooke, Hancock, Jackson, Marshall, Mason, Ohio and 6 more	86 min

Nearby

Tornado Watches in West Virginia, 2014 Tornado Watches in Virginia, 2014 Every tornado watch in 2014

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.