Alert archive / North Carolina / Severe Thunderstorm Watches in 2021

Severe Thunderstorm Watch 68

March 28, 202132 counties in North Carolina; 8 counties in Virginia

The Storm Prediction Center issued this severe thunderstorm watch at Mar 28, 2021, 3:24 PM EDT for 32 counties in North Carolina; 8 counties in Virginia. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Mar 28, 2021, 3:24 PM EDT (19:24 UTC)
Expired
Mar 28, 2021, 7:02 PM EDT
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
1 in
Strongest gust expected
60 kt
All 40 counties

Beaufort County, NC, Bertie County, NC, Camden County, NC, Chowan County, NC, Craven County, NC, Cumberland County, NC, Currituck County, NC, Duplin County, NC, Edgecombe County, NC, Gates County, NC, Greene County, NC, Halifax County, NC, Harnett County, NC, Hertford County, NC, Hoke County, NC, Johnston County, NC, Jones County, NC, Lenoir County, NC, Martin County, NC, Nash County, NC, Northampton County, NC, Onslow County, NC, Pamlico County, NC, Pasquotank County, NC, Perquimans County, NC, Pitt County, NC, Sampson County, NC, Scotland County, NC, Tyrrell County, NC, Washington County, NC, Wayne County, NC, Wilson County, NC, City of Chesapeake, VA, City of Franklin, VA, City of Norfolk, VA, City of Portsmouth, VA, City of Suffolk, VA, City of Virginia Beach, VA, Isle of Wight County, VA, Southampton County, VA

The radar

The Raleigh/Durham radar (KRAX), 82 km from the middle of the area, began a volume at 19:28 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
20%
One or more EF2 to EF5 tornadoes
5%
Ten or more severe wind reports
50%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
20%
One or more hailstones of 2 inches or more
10%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Mar 28, 3:39 PM EDTSevere Thunderstorm WarningAKQBertie51 min
Mar 28, 3:50 PM EDTSevere Thunderstorm WarningRAHEdgecombe, Wilson40 min
Mar 28, 4:06 PM EDTSevere Thunderstorm WarningMHXMartin, Pitt39 min
Mar 28, 4:27 PM EDTSevere Thunderstorm WarningAKQBertie24 min
Mar 28, 5:32 PM EDTSevere Thunderstorm WarningAKQCamden, Currituck, Pasquotank25 min
Mar 28, 5:32 PM EDTSevere Thunderstorm WarningMHXBeaufort, Craven, Duplin, Jones, Onslow, Pamlico43 min
Mar 28, 5:34 PM EDTSevere Thunderstorm WarningMHXTyrrell, Washington26 min
Mar 28, 5:59 PM EDTTornado WarningMHXTyrrell19 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

Newport, NC (KMHX), launched 12:00Z, 7.4 hours before the alert went out and 127 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, Newport, NC at 12:00Z on 2021-03-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 184 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, Newport, NC at 12:00Z on 2021-03-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 171 square meters per square second.1939587897Sfc1 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
184 J/kg
Mixed-layer CIN
-190 J/kg
Mixed-layer LCL
936 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
171 m²/s²
0-3 km storm-relative helicity
79 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.8

Open this sounding in Storm Lab

The text

As transmitted.

680 
WWUS20 KWNS 281922
SEL8  
SPC WW 281922
NCZ000-VAZ000-CWZ000-290100-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 68
NWS Storm Prediction Center Norman OK
325 PM EDT Sun Mar 28 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  East central and northeast North Carolina
  Southeast Virginia
  Coastal Waters

* Effective this Sunday afternoon and evening from 325 PM until
  900 PM EDT.

* Primary threats include...
  Scattered damaging wind gusts to 70 mph possible
  Isolated large hail events to 1 inch in diameter possible
  A tornado or two possible

SUMMARY...Scattered thunderstorms have developed along a pre-frontal
trough across North Carolina, and additional storms may form along a
sea breeze boundary farther to the east.  The storms will spread
northeastward toward southeast Virginia and will be capable of
producing damaging winds, as well as an isolated tornado and
marginally severe hail through this evening.

The severe thunderstorm watch area is approximately along and 70
statute miles east and west of a line from 35 miles east of
Fayetteville NC to 15 miles east northeast of Norfolk VA. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU8).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for 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. Severe thunderstorms can and occasionally do produce
tornadoes.

&&

AVIATION...A few severe thunderstorms with hail surface and aloft to
1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few
cumulonimbi with maximum tops to 500. Mean storm motion vector
24045.

...Thompson

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 28, 2:25 AM EDTMesoscale DiscussionSPCAvery, Buncombe, Cherokee, Clay, Graham, Haywood and 7 more2 hr
Mar 28, 3:07 AM EDTSevere Thunderstorm WatchSPCCherokee, Clay, Graham, Macon, Swain6 hr
Mar 28, 12:38 PM EDTMesoscale DiscussionSPCAlamance, Anson, Cabarrus, Caswell, Chatham, Cumberland and 19 more3 hr
Mar 28, 4:53 PM EDTMesoscale DiscussionSPCBeaufort, Bertie, Camden, Chowan, Craven, Currituck and 13 more67 min
Mar 28, 1:24 PM EDTMesoscale DiscussionSPCAccomack, Amelia, Appomattox, Arlington, Brunswick, Buckingham and 66 more2 hr
Mar 28, 5:05 PM EDTSevere Thunderstorm WatchSPCArlington, Fairfax, Fauquier, Prince William, Stafford, City of Alexandria and 3 more4 hr

Nearby

Severe Thunderstorm Watches in North Carolina, 2021Severe Thunderstorm Watches in Virginia, 2021Every severe thunderstorm watch in 2021

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.