Alert archive / North Carolina / Tornado Watches in 2014

Tornado Watch 448

July 27, 201433 counties in North Carolina

The Storm Prediction Center issued this tornado watch at Jul 27, 2014, 6:32 PM EDT for 33 counties in North Carolina. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Jul 27, 2014, 6:32 PM EDT (22:32 UTC)
Expired
Jul 28, 2014, 1:00 AM EDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
3 in
Strongest gust expected
60 kt
All 33 counties

Alexander County, NC, Alleghany County, NC, Ashe County, NC, Avery County, NC, Buncombe County, NC, Burke County, NC, Cabarrus County, NC, Caldwell County, NC, Catawba County, NC, Cleveland County, NC, Davie County, NC, Gaston County, NC, Graham County, NC, Haywood County, NC, Henderson County, NC, Iredell County, NC, Jackson County, NC, Lincoln County, NC, Macon County, NC, Madison County, NC, McDowell County, NC, Mecklenburg County, NC, Mitchell County, NC, Polk County, NC, Rowan County, NC, Rutherford County, NC, Surry County, NC, Swain County, NC, Transylvania County, NC, Watauga County, NC, Wilkes County, NC, Yadkin County, NC, Yancey County, NC

The radar

The Greer radar (KGSP), 100 km from the middle of the area, began a volume at 22:33 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
50%
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

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

IssuedProductOfficeCountiesLasted
Jul 27, 6:45 PM EDTTornado WarningGSPAvery29 min
Jul 27, 7:19 PM EDTSevere Thunderstorm WarningRNKAshe, Watauga56 min
Jul 27, 7:49 PM EDTSevere Thunderstorm WarningGSPAlexander, Caldwell, Catawba, Iredell56 min
Jul 27, 8:03 PM EDTSevere Thunderstorm WarningGSPHaywood, Madison, Swain57 min
Jul 27, 8:27 PM EDTSevere Thunderstorm WarningGSPBuncombe, Haywood, Jackson, Madison, Swain63 min
Jul 27, 8:49 PM EDTSevere Thunderstorm WarningGSPBuncombe, Henderson, McDowell, Polk, Rutherford, Transylvania56 min
Jul 27, 9:01 PM EDTSevere Thunderstorm WarningGSPGraham, Haywood, Jackson, Swain59 min
Jul 27, 9:25 PM EDTSevere Thunderstorm WarningGSPCleveland, Polk, Rutherford65 min
Jul 27, 9:28 PM EDTSevere Thunderstorm WarningGSPHaywood, Henderson, Jackson, Transylvania62 min
Jul 27, 9:54 PM EDTSevere Thunderstorm WarningGSPHaywood, Jackson, Transylvania66 min
Jul 27, 9:58 PM EDTSevere Thunderstorm WarningGSPHaywood, Jackson, Swain62 min
Jul 27, 10:48 PM EDTSevere Thunderstorm WarningGSPBuncombe, Haywood, Henderson, Transylvania27 min
Jul 27, 11:48 PM EDTSevere Thunderstorm WarningGSPHaywood, Madison, Yancey57 min
Jul 28, 12:20 AM EDTSevere Thunderstorm WarningGSPBuncombe, Haywood, McDowell, Madison, Yancey55 min
Jul 28, 12:40 AM EDTSevere Thunderstorm WarningGSPBuncombe, Haywood, Jackson, Madison, Swain65 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

Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 10.5 hours before the alert went out and 200 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-pSkew-T log-p diagram, Greensboro/Hi Pt, NC at 12:00Z on 2014-07-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 116 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Greensboro/Hi Pt, NC at 12:00Z on 2014-07-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -70 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
116 J/kg
Mixed-layer CIN
-224 J/kg
Mixed-layer LCL
1295 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
-70 m²/s²
0-3 km storm-relative helicity
70 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

441 
WWUS20 KWNS 272235
SEL8  
SPC WW 272235
NCZ000-VAZ000-280500-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 448
NWS STORM PREDICTION CENTER NORMAN OK
635 PM EDT SUN JUL 27 2014

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF 
  WESTERN NORTH CAROLINA
  SMALL PART OF SOUTHWESTERN VIRGINIA

* EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING FROM 635 PM
  UNTIL 100 AM EDT.

* PRIMARY THREATS INCLUDE...
  A FEW TORNADOES POSSIBLE
  ISOLATED VERY LARGE HAIL EVENTS TO 3 INCHES IN DIAMETER POSSIBLE
  ISOLATED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 70 STATUTE
MILES EAST AND WEST OF A LINE FROM 15 MILES SOUTH SOUTHEAST OF
ASHEVILLE NORTH CAROLINA TO 65 MILES NORTH NORTHEAST OF HICKORY
NORTH CAROLINA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU8).

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 445...WW 446...WW 447...

DISCUSSION...POTENTIAL EXISTS FOR SUPERCELLS IN WW 445 TO SURVIVE
PASSAGE THROUGH NARROW CORRIDOR OF RELATIVELY LOW-THETAE AIR MASS
OVER HIGHEST APPALACHIANS AND MOVE INTO FAVORABLY MOIST/UNSTABLE
ENVIRONMENT OF WRN PIEDMONT REGION...WHERE 50 KT EFFECTIVE-SHEAR
MAGNITUDES AND 200-300 J/KG EFFECTIVE SRH WILL JUXTAPOSE WITH
UPPER-60S/LOWER-70S F SFC DEW POINTS.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 30030.


...EDWARDS

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 27, 10:08 AM EDTMesoscale DiscussionSPCBeaufort, Bertie, Bladen, Camden, Chowan, Craven and 28 more67 min
Jul 27, 4:49 PM EDTMesoscale DiscussionSPCAlexander, Alleghany, Ashe, Avery, Burke, Caldwell and 13 more116 min
Jul 27, 1:00 PM EDTTornado WatchSPCAnderson, Blount, Campbell, Carter, Claiborne, Clay and 25 more11 hr
Jul 27, 3:14 PM EDTMesoscale DiscussionSPCAnderson, Campbell, Carter, Claiborne, Clay, Fentress and 22 more2 hr
Jul 27, 7:28 PM EDTMesoscale DiscussionSPCAnderson, Campbell, Claiborne, Clay, Cocke, Fentress and 16 more92 min

Nearby

Tornado Watches in North Carolina, 2014Every 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.