Alert archive / Virginia / Tornado Watches in 2017

Tornado Watch 196

May 5, 201715 counties in North Carolina; 25 counties in Virginia

The Storm Prediction Center issued this tornado watch at May 5, 2017, 6:25 AM EDT for 15 counties in North Carolina; 25 counties in Virginia. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
May 5, 2017, 6:25 AM EDT (10:25 UTC)
Expired
May 5, 2017, 11:03 AM EDT
In force
5 hr
Issued by
the Storm Prediction Center
Largest hail expected
0.5 in
Strongest gust expected
60 kt
All 40 counties

Beaufort County, NC, Bertie County, NC, Camden County, NC, Chowan County, NC, Currituck County, NC, Dare County, NC, Gates County, NC, Hertford County, NC, Hyde County, NC, Martin County, NC, Northampton County, NC, Pasquotank County, NC, Perquimans County, NC, Tyrrell County, NC, Washington County, NC, Charles City County, VA, City of Chesapeake, VA, City of Emporia, VA, City of Franklin, VA, City of Hampton, VA, City of Hopewell, VA, City of Newport News, VA, City of Norfolk, VA, City of Poquoson, VA, City of Portsmouth, VA, City of Suffolk, VA, City of Virginia Beach, VA, City of Williamsburg, VA, Gloucester County, VA, Greensville County, VA, Isle of Wight County, VA, James City County, VA, Mathews County, VA, New Kent County, VA, Northampton County, VA, Prince George County, VA, Southampton County, VA, Surry County, VA, Sussex County, VA, York County, VA

The radar

The Norfolk radar (KAKQ), 57 km from the middle of the area, began a volume at 10:27 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
10%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
60%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
May 5, 6:28 AM EDTTornado WarningMHXBeaufort, Craven, Jones, Pitt32 min
May 5, 6:38 AM EDTSevere Thunderstorm WarningAKQNorthampton52 min
May 5, 6:52 AM EDTTornado WarningAKQBertie23 min
May 5, 6:54 AM EDTTornado WarningMHXMartin21 min
May 5, 7:03 AM EDTTornado WarningMHXBeaufort, Craven, Pitt42 min
May 5, 7:13 AM EDTTornado WarningAKQBertie, Chowan32 min
May 5, 7:20 AM EDTSevere Thunderstorm WarningAKQCharles City, Chesterfield, Dinwiddie, Greensville, Henrico, James City and 9 more40 min
May 5, 7:30 AM EDTTornado WarningMHXMartin, Washington30 min
May 5, 7:34 AM EDTTornado WarningAKQBertie26 min
May 5, 7:39 AM EDTSevere Thunderstorm WarningAKQCaroline, Essex, Hanover, Henrico, King and Queen, King William and 4 more51 min
May 5, 7:44 AM EDTTornado WarningMHXMartin, Washington6 min
May 5, 7:54 AM EDTSevere Thunderstorm WarningAKQCharles City, Essex, Gloucester, Henrico, James City, King and Queen and 9 more51 min
May 5, 8:02 AM EDTTornado WarningAKQCamden, Currituck, Pasquotank28 min
May 5, 8:08 AM EDTSevere Thunderstorm WarningAKQCamden, Gates, Pasquotank52 min
May 5, 8:26 AM EDTTornado WarningAKQCity of Virginia Beach34 min
May 5, 8:29 AM EDTSevere Thunderstorm WarningAKQCamden, Chowan, Currituck, Gates, Pasquotank, Perquimans46 min
May 5, 8:40 AM EDTSevere Thunderstorm WarningAKQEssex, Gloucester, James City, King and Queen, Lancaster, Mathews and 5 more50 min
May 5, 9:00 AM EDTSevere Thunderstorm WarningAKQCamden, Currituck, Pasquotank, Perquimans60 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

Wallops Is Stn, VA (KWAL), launched 00:00Z, 10.4 hours before the alert went out and 144 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, Wallops Is Stn, VA at 00:00Z on 2017-05-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Wallops Is Stn, VA at 00:00Z on 2017-05-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 219 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
876 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
219 m²/s²
0-3 km storm-relative helicity
359 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

651 
WWUS20 KWNS 051020
SEL6  
SPC WW 051020
NCZ000-VAZ000-CWZ000-051700-

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 196
NWS Storm Prediction Center Norman OK
620 AM EDT Fri May 5 2017

The NWS Storm Prediction Center has issued a

* Tornado Watch for portions of 
  northeastern North Carolina
  southeastern Virginia
  Coastal Waters

* Effective this Friday morning and afternoon from 620 AM until
  100 PM EDT.

* Primary threats include...
  A couple tornadoes possible
  Isolated damaging wind gusts to 70 mph possible

SUMMARY...An evolving band of thunderstorms, as well as isolated
supercells, are expected to overspread the area through mid morning,
accompanied by locally damaging wind gusts and perhaps a couple of
tornadoes.

The tornado watch area is approximately along and 50 statute miles
east and west of a line from 45 miles north of Norfolk VA to 25
miles south of Elizabeth City NC. For a complete depiction of the
watch see the associated watch outline update (WOUS64 KWNS WOU6).

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 195...

AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 0.5 inches. Extreme turbulence and surface wind
gusts to 60 knots. A few cumulonimbi with maximum tops to 400. Mean
storm motion vector 21035.

...Kerr

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 4, 8:49 PM EDTTornado WatchSPCBladen, Brunswick, Carteret, Columbus, Craven, Cumberland and 13 more6 hr
May 4, 11:24 PM EDTMesoscale DiscussionSPCBladen, Brunswick, Columbus, Duplin, Greene, Jones and 7 more66 min
May 5, 2:28 AM EDTMesoscale DiscussionSPCAlamance, Beaufort, Bertie, Bladen, Camden, Caswell and 43 more92 min
May 5, 3:09 AM EDTTornado WatchSPCAlamance, Anson, Bladen, Brunswick, Carteret, Chatham and 37 more6 hr
May 5, 5:56 AM EDTMesoscale DiscussionSPCBeaufort, Bertie, Camden, Chowan, Currituck, Dare and 12 more94 min
May 5, 8:27 AM EDTMesoscale DiscussionSPCBeaufort, Bertie, Camden, Carteret, Chowan, Craven and 9 more93 min
May 5, 6:15 PM EDTMesoscale DiscussionSPCHalifax, Hertford, Northampton90 min

Nearby

Tornado Watches in Virginia, 2017Tornado Watches in North Carolina, 2017Every tornado watch in 2017

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.