Alert archive / North Carolina / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 7, NWS Raleigh, NC

March 18, 2021Alamance County, Orange County, North Carolina

NWS Raleigh, NC issued this severe thunderstorm warning at Mar 18, 2021, 6:09 PM EDT for Alamance County, Orange County, North Carolina. It was in force for 66 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: Mar 18, 2021, 6:09 PM EDT (22:09 UTC)
Expired: Mar 18, 2021, 7:15 PM EDT
In force: 66 min
Issued by: NWS Raleigh, NC
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

Counties Alamance County, NC, Orange County, NC

The radar

The Raleigh/Durham radar (KRAX), 71 km from the middle of the area, began a volume at 22:08 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Mar 18, 4:45 PM EDT	Tornado Watch	SPC	4 hr

The nearest sounding before it

Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 10.2 hours before the alert went out and 65 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 486 m above ground
0-6 km bulk shear: 67 kt
0-1 km storm-relative helicity: 470 m²/s²
0-3 km storm-relative helicity: 562 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

765 
WUUS52 KRAH 182209
SVRRAH
NCC001-135-182315-
/O.NEW.KRAH.SV.W.0007.210318T2209Z-210318T2315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Raleigh NC
609 PM EDT Thu Mar 18 2021

The National Weather Service in Raleigh has issued a

* Severe Thunderstorm Warning for...
  Southern Alamance County in central North Carolina...
  Orange County in central North Carolina...

* Until 715 PM EDT.

* At 609 PM EDT, a severe thunderstorm was located 11 miles south of
  Graham, moving northeast at 45 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Chapel Hill, Hillsborough, Carrboro, Swepsonville, Efland, Snow
  Camp, Eno River State Park, Sutphin, Cane Creek Reservoir and
  Saxapahaw.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 900 PM EDT for central North
Carolina.

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

For your protection move to an interior room on the lowest floor of a
building.

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

&&

LAT...LON 3587 7902 3586 7911 3588 7925 3585 7924
      3584 7954 3599 7954 3617 7896
TIME...MOT...LOC 2209Z 238DEG 39KT 3590 7944 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$

Leins

1 follow-up statement

642 
WWUS52 KRAH 182312
SVSRAH

Severe Weather Statement
National Weather Service Raleigh NC
712 PM EDT Thu Mar 18 2021

NCC001-135-182322-
/O.EXP.KRAH.SV.W.0007.000000T0000Z-210318T2315Z/
Alamance NC-Orange NC-
712 PM EDT Thu Mar 18 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN ALAMANCE AND ORANGE
COUNTIES WILL EXPIRE AT 715 PM 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 are still possible with this thunderstorm.

A Tornado Watch remains in effect until 900 PM EDT for central North
Carolina.

LAT...LON 3587 7902 3586 7911 3588 7925 3585 7924
      3584 7954 3599 7954 3617 7896
TIME...MOT...LOC 2312Z 238DEG 39KT 3626 7873 

$$

Leins

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 18, 3:55 PM EDT	Special Weather Statement	RAH	Davidson, Forsyth	65 min
Mar 18, 4:41 PM EDT	Tornado Warning	RAH	Davidson, Forsyth, Guilford	31 min
Mar 18, 4:54 PM EDT	Tornado Warning	RAH	Guilford, Randolph	66 min
Mar 18, 5:07 PM EDT	Severe Thunderstorm Warning	RAH	Halifax	23 min
Mar 18, 5:13 PM EDT	Severe Thunderstorm Warning	RAH	Alamance, Chatham, Davidson, Guilford, Randolph	62 min
Mar 18, 5:34 PM EDT	Tornado Warning	RAH	Alamance, Guilford	26 min
Mar 18, 5:37 PM EDT	Severe Thunderstorm Warning	RAH	Montgomery, Randolph, Stanly	38 min
Mar 18, 5:58 PM EDT	Tornado Warning	RAH	Alamance, Durham, Orange, Person	62 min
Mar 18, 6:07 PM EDT	Severe Thunderstorm Warning	RAH	Anson, Richmond	38 min
Mar 18, 6:13 PM EDT	Severe Thunderstorm Warning	RAH	Montgomery, Moore, Randolph, Stanly	47 min
Mar 18, 6:39 PM EDT	Tornado Warning	RAH	Durham, Orange	34 min
Mar 18, 6:41 PM EDT	Tornado Warning	RAH	Granville	34 min
Mar 18, 6:45 PM EDT	Severe Thunderstorm Warning	RAH	Anson, Hoke, Montgomery, Moore, Richmond	45 min
Mar 18, 6:57 PM EDT	Tornado Warning	RAH	Granville	48 min
Mar 18, 6:59 PM EDT	Severe Thunderstorm Warning	RAH	Alamance, Chatham, Orange, Randolph	21 min
Mar 18, 7:11 PM EDT	Tornado Warning	RAH	Halifax, Vance, Warren	54 min
Mar 18, 7:12 PM EDT	Special Weather Statement	RAH	Durham, Orange	63 min
Mar 18, 7:25 PM EDT	Tornado Warning	RAH	Franklin, Vance, Warren	47 min
Mar 18, 7:30 PM EDT	Severe Thunderstorm Warning	RAH	Cumberland, Harnett, Hoke, Lee, Moore	45 min
Mar 18, 7:41 PM EDT	Special Weather Statement	RAH	Hoke, Scotland	64 min

Nearby

Severe Thunderstorm Warnings in North Carolina, 2021 Every 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.