Alert archive / North Carolina / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 118, NWS Raleigh, NC

August 18, 20215 counties in North Carolina

NWS Raleigh, NC issued this severe thunderstorm warning at Aug 18, 2021, 2:58 AM EDT for 5 counties in North Carolina. It was in force for 47 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 18, 2021, 2:58 AM EDT (06:58 UTC)
Expired
Aug 18, 2021, 3:45 AM EDT
In force
47 min
Issued by
NWS Raleigh, NC
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Alamance County, NC, Chatham County, NC, Montgomery County, NC, Moore County, NC, Randolph County, NC

The radar

The Raleigh/Durham radar (KRAX), 95 km from the middle of the area, began a volume at 07:00 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.

The nearest sounding before it

Greensboro/Hi Pt, NC (KGSO), launched 00:00Z, 7.0 hours before the alert went out and 46 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 00:00Z on 2021-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 349 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Greensboro/Hi Pt, NC at 00:00Z on 2021-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 225 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
349 J/kg
Mixed-layer CIN
-15 J/kg
Mixed-layer LCL
641 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
225 m²/s²
0-3 km storm-relative helicity
278 m²/s²
Significant tornado parameter
0.2
Supercell composite
2.5

Open this sounding in Storm Lab

The text

As transmitted.

745 
WUUS52 KRAH 180658
SVRRAH
NCC001-037-123-125-151-180745-
/O.NEW.KRAH.SV.W.0118.210818T0658Z-210818T0745Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Raleigh NC
258 AM EDT Wed Aug 18 2021

The National Weather Service in Raleigh has issued a

* Severe Thunderstorm Warning for...
  Southern Alamance County in central North Carolina...
  Northwestern Moore County in central North Carolina...
  Northeastern Montgomery County in central North Carolina...
  Eastern Randolph County in central North Carolina...
  Northwestern Chatham County in central North Carolina...

* Until 345 AM EDT.

* At 257 AM EDT, a severe thunderstorm was located over Seagrove, or
  9 miles south of North Carolina Zoo, moving northeast at 45 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  North Carolina Zoo, Siler City, Seagrove, Liberty, Ramseur,
  Franklinville, Swepsonville, Star, Staley and Steeds.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Straight line winds can blow down trees, power lines, and damage
mobile homes and other buildings. Seek shelter in a sturdy structure
until the storm has passed. Stay away from windows as flying debris
generated by damaging winds can be deadly.

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

&&

LAT...LON 3590 7959 3590 7954 3597 7954 3600 7949
      3602 7931 3597 7926 3588 7926 3587 7923
      3538 7973 3539 7982 3548 7992
TIME...MOT...LOC 0657Z 216DEG 40KT 3550 7978 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

26
3 follow-up statements
801 
WWUS52 KRAH 180710
SVSRAH

Severe Weather Statement
National Weather Service Raleigh NC
310 AM EDT Wed Aug 18 2021

NCC123-180720-
/O.CAN.KRAH.SV.W.0118.000000T0000Z-210818T0745Z/
Montgomery NC-
310 AM EDT Wed Aug 18 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN MONTGOMERY COUNTY
IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 3590 7959 3590 7954 3597 7954 3600 7949
      3602 7931 3597 7926 3588 7926 3587 7923
      3538 7973 3551 7977 3551 7984 3558 7984
TIME...MOT...LOC 0710Z 211DEG 30KT 3560 7975 

$$

NCC001-037-125-151-180745-
/O.CON.KRAH.SV.W.0118.000000T0000Z-210818T0745Z/
Alamance NC-Moore NC-Randolph NC-Chatham NC-
310 AM EDT Wed Aug 18 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 345 AM EDT
FOR SOUTHERN ALAMANCE...NORTHWESTERN MOORE...EASTERN RANDOLPH AND
NORTHWESTERN CHATHAM COUNTIES...

At 310 AM EDT, a severe thunderstorm was located over North Carolina
Zoo, moving northeast at 35 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
North Carolina Zoo, Siler City, Seagrove, Liberty, Ramseur,
Franklinville, Swepsonville, Staley, Snow Camp and Sutphin.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Straight line winds can blow down trees, power lines, and damage
mobile homes and other buildings. Seek shelter in a sturdy structure
until the storm has passed. Stay away from windows as flying debris
generated by damaging winds can be deadly.

&&

LAT...LON 3590 7959 3590 7954 3597 7954 3600 7949
      3602 7931 3597 7926 3588 7926 3587 7923
      3538 7973 3551 7977 3551 7984 3558 7984
TIME...MOT...LOC 0710Z 211DEG 30KT 3560 7975 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

26
509 
WWUS52 KRAH 180726
SVSRAH

Severe Weather Statement
National Weather Service Raleigh NC
326 AM EDT Wed Aug 18 2021

NCC125-180735-
/O.CAN.KRAH.SV.W.0118.000000T0000Z-210818T0745Z/
Moore NC-
326 AM EDT Wed Aug 18 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN MOORE COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 3597 7926 3588 7926 3587 7923 3551 7960
      3551 7975 3557 7972 3569 7976 3590 7959
      3590 7954 3597 7954 3600 7949 3602 7931
TIME...MOT...LOC 0725Z 213DEG 27KT 3570 7967 

$$

NCC001-037-151-180745-
/O.CON.KRAH.SV.W.0118.000000T0000Z-210818T0745Z/
Alamance NC-Randolph NC-Chatham NC-
326 AM EDT Wed Aug 18 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 345 AM EDT
FOR SOUTHERN ALAMANCE...EASTERN RANDOLPH AND NORTHWESTERN CHATHAM
COUNTIES...

At 325 AM EDT, a severe thunderstorm was located 2 miles southwest 
of Ramseur, moving northeast at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Siler City, North Carolina Zoo, Liberty, Ramseur, Franklinville,
Swepsonville, Staley, Snow Camp, Coleridge and Hasty.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Straight line winds can blow down trees, power lines, and damage
mobile homes and other buildings. Seek shelter in a sturdy structure
until the storm has passed. Stay away from windows as flying debris
generated by damaging winds can be deadly.

&&

LAT...LON 3597 7926 3588 7926 3587 7923 3551 7960
      3551 7975 3557 7972 3569 7976 3590 7959
      3590 7954 3597 7954 3600 7949 3602 7931
TIME...MOT...LOC 0725Z 213DEG 27KT 3570 7967 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

26
634 
WWUS52 KRAH 180740
SVSRAH

Severe Weather Statement
National Weather Service Raleigh NC
340 AM EDT Wed Aug 18 2021

NCC001-037-151-180750-
/O.EXP.KRAH.SV.W.0118.000000T0000Z-210818T0745Z/
Alamance NC-Randolph NC-Chatham NC-
340 AM EDT Wed Aug 18 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN ALAMANCE...EASTERN
RANDOLPH AND NORTHWESTERN CHATHAM COUNTIES WILL EXPIRE AT 345 AM
EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However, gusty 
winds up to 40 mph are still possible with this thunderstorm.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Raleigh.

LAT...LON 3597 7926 3588 7926 3587 7923 3551 7960
      3551 7975 3557 7972 3569 7976 3590 7959
      3590 7954 3597 7954 3600 7949 3602 7931
TIME...MOT...LOC 0740Z 216DEG 40KT 3582 7956 

$$

26

The office that day

Everything else NWS Raleigh, NC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 18, 12:31 AM EDTSpecial Weather StatementRAHAnson, Davidson, Forsyth, Stanly59 min
Aug 18, 1:18 AM EDTSpecial Weather StatementRAHAnson, Davidson, Forsyth, Guilford, Montgomery, Randolph57 min
Aug 18, 2:12 AM EDTAreal Flood AdvisoryRAHAnson, Montgomery, Richmond, Stanly2 hr
Aug 18, 2:28 AM EDTSpecial Weather StatementRAHMontgomery32 min
Aug 18, 2:31 AM EDTSpecial Weather StatementRAHAnson, Richmond44 min
Aug 18, 3:01 AM EDTAreal Flood AdvisoryRAHMontgomery, Moore, Randolph118 min
Aug 18, 3:18 AM EDTSpecial Weather StatementRAHMoore, Richmond57 min
Aug 18, 3:25 AM EDTAreal Flood AdvisoryRAHAnson, Montgomery, Moore, Richmond3 hr
Aug 18, 4:37 AM EDTSpecial Weather StatementRAHLee53 min
Aug 18, 5:04 AM EDTSpecial Weather StatementRAHChatham41 min
Aug 18, 5:35 AM EDTAreal Flood AdvisoryRAHHoke, Moore, Scotland115 min
Aug 18, 5:58 AM EDTSpecial Weather StatementRAHScotland47 min
Aug 18, 7:45 AM EDTSpecial Weather StatementRAHCumberland60 min
Aug 18, 10:54 AM EDTSpecial Weather StatementRAHSampson66 min
Aug 18, 12:17 PM EDTSpecial Weather StatementRAHWayne, Wilson58 min

Nearby

Severe Thunderstorm Warnings in North Carolina, 2021Every severe thunderstorm warning 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.