Alert archive / North Carolina / Tornado Warnings in 2021

Tornado Warning 11, NWS Blacksburg, VA

August 17, 2021Alleghany County, Wilkes County, North Carolina

NWS Blacksburg, VA issued this tornado warning at Aug 17, 2021, 1:48 PM EDT for Alleghany County, Wilkes County, North Carolina. It was in force for 42 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Aug 17, 2021, 1:48 PM EDT (17:48 UTC)
Expired: Aug 17, 2021, 2:30 PM EDT
In force: 42 min
Issued by: NWS Blacksburg, VA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.0 in

Counties Alleghany County, NC, Wilkes County, NC

The radar

The Roanoke radar (KFCX), 91 km from the middle of the area, began a volume at 17:49 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 was reported inside it

Time	Report	Where	Remark
Aug 17, 1:56 PM EDT	TSTM WND DMG	3 S Glade Valley, NC	A COUPLE OF TREES BLOWN DOWN ON THE BLUE RIDGE PARKWAY.
Aug 17, 2:04 PM EDT	TSTM WND DMG	1 Se Glade Valley, NC	ONE OR TWO TREES BLOWN DOWN.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

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

Issued	Product	Office	Lasted
Aug 17, 1:06 PM EDT	Tornado Watch	SPC	5 hr

The nearest sounding before it

Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 5.8 hours before the alert went out and 106 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: 522 J/kg
Mixed-layer CIN: -5 J/kg
Mixed-layer LCL: 593 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 77 m²/s²
0-3 km storm-relative helicity: 99 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.9

Open this sounding in Storm Lab

The text

As transmitted.

460 
WFUS51 KRNK 171748
TORRNK
NCC005-193-171830-
/O.NEW.KRNK.TO.W.0011.210817T1748Z-210817T1830Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service BLACKSBURG VA
148 PM EDT Tue Aug 17 2021

The National Weather Service in BLACKSBURG has issued a

* Tornado Warning for...
  Eastern Alleghany County in northwestern North Carolina...
  Northeastern Wilkes County in northwestern North Carolina...

* Until 230 PM EDT.
    
* At 147 PM EDT, a severe thunderstorm capable of producing a tornado
  was located over Traphill, moving north at 20 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation. This storm has had a history of
           producing tornadoes across Wilkes and Yadkin counties 
           during the past hour.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* Locations impacted include...
  Sparta...
  Traphill...
  Ennice...
  Roaring Gap...
  Stone Mountain State Park...
  Glade Valley...
  and Barrett.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

Locally heavy rain will quickly reduce visibility and result in
ponding of water on roadways, standing water in low lying areas, and
minor flooding of creeks, streams, and areas of poor drainage.
Drivers are urged to slow down and use extra caution to avoid
hydroplaning.

When it is safe to do so, please send your reports of hail of any
size, as well as reports of any wind damage, including downed trees
or large limbs, to the National Weather Service by calling toll free
at 1...8 6 6...2 1 5...4 3 2 4. Reports and pictures can also be
shared on the National Weather Service Blacksburg Facebook page and
on Twitter.

&&

LAT...LON 3657 8115 3656 8096 3648 8094 3644 8098
      3642 8095 3640 8097 3637 8092 3635 8092
      3629 8103
TIME...MOT...LOC 1747Z 169DEG 18KT 3636 8100 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...0.00 IN

$$

RAB

2 follow-up statements

115 
WWUS51 KRNK 171807
SVSRNK

Severe Weather Statement
National Weather Service BLACKSBURG VA
207 PM EDT Tue Aug 17 2021

NCC193-171815-
/O.CAN.KRNK.TO.W.0011.000000T0000Z-210817T1830Z/
Wilkes NC-
207 PM EDT Tue Aug 17 2021

...THE TORNADO WARNING FOR NORTHEASTERN WILKES COUNTY IS CANCELLED...
    
The tornadic thunderstorm which prompted the warning has moved
out of the warned area. Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 700 PM EDT for northwestern
North Carolina...and southwestern Virginia.

LAT...LON 3642 8107 3644 8109 3657 8115 3656 8096
      3648 8094 3644 8098 3641 8105
TIME...MOT...LOC 1805Z 169DEG 18KT 3645 8102 

$$

NCC005-171830-
/O.CON.KRNK.TO.W.0011.000000T0000Z-210817T1830Z/
Alleghany NC-
207 PM EDT Tue Aug 17 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 230 PM EDT FOR 
EASTERN ALLEGHANY COUNTY IN NORTHWESTERN NORTH CAROLINA...
    
At 205 PM EDT, a severe thunderstorm capable of producing a tornado
was located over Glade Valley, or near Ennice, moving north at 20
mph. Law enforcement has reported tornadoes with this storm during
the past hour in Wilkes and Yadkin counties.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

Locations impacted include...
Sparta...
Ennice...
Glade Valley...
and Barrett.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

Locally heavy rain will quickly reduce visibility and result in
ponding of water on roadways, standing water in low lying areas, and
minor flooding of creeks, streams, and areas of poor drainage.
Drivers are urged to slow down and use extra caution to avoid
hydroplaning.

When it is safe to do so, please send your reports of hail of any
size, as well as reports of any wind damage, including downed trees
or large limbs, to the National Weather Service by calling toll free
at 1...8 6 6...2 1 5...4 3 2 4. Reports and pictures can also be
shared on the National Weather Service Blacksburg Facebook page and
on Twitter.

&&

LAT...LON 3642 8107 3644 8109 3657 8115 3656 8096
      3648 8094 3644 8098 3641 8105
TIME...MOT...LOC 1805Z 169DEG 18KT 3645 8102 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...0.00 IN

$$

RAB

122 
WWUS51 KRNK 171823
SVSRNK

Severe Weather Statement
National Weather Service BLACKSBURG VA
223 PM EDT Tue Aug 17 2021

NCC005-171833-
/O.EXP.KRNK.TO.W.0011.000000T0000Z-210817T1830Z/
Alleghany NC-
223 PM EDT Tue Aug 17 2021

...THE TORNADO WARNING FOR EASTERN ALLEGHANY COUNTY IN NORTHWESTERN
NORTH CAROLINA WILL EXPIRE AT 230 PM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning will be allowed to expire.  However heavy rain
is still possible with this thunderstorm.

A Tornado Watch remains in effect until 700 PM EDT for northwestern
North Carolina...and southwestern Virginia.

LAT...LON 3642 8107 3644 8109 3657 8115 3656 8096
      3648 8094 3644 8098 3641 8105
TIME...MOT...LOC 1823Z 169DEG 18KT 3653 8104 

$$

RAB

The office that day

Everything else NWS Blacksburg, VA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 17, 3:37 AM EDT	Flash Flood Watch	RNK	Alleghany, Ashe, Surry, Watauga, Wilkes	24 hr
Aug 17, 11:48 AM EDT	Tornado Warning Tornado observed	RNK	Wilkes	42 min
Aug 17, 12:35 PM EDT	Tornado Warning Tornado observed	RNK	Wilkes, Yadkin	40 min
Aug 17, 12:46 PM EDT	Special Weather Statement	RNK	Wilkes	44 min
Aug 17, 1:19 PM EDT	Tornado Warning	RNK	Wilkes	41 min
Aug 17, 1:58 PM EDT	Special Weather Statement	RNK	Alleghany, Caswell, Rockingham, Stokes, Surry, Yadkin	32 min
Aug 17, 2:18 PM EDT	Tornado Warning	RNK	Caswell	32 min
Aug 17, 2:43 PM EDT	Tornado Warning	RNK	Rockingham, Stokes	32 min
Aug 17, 4:35 PM EDT	Special Weather Statement	RNK	Surry	25 min
Aug 17, 5:05 PM EDT	Special Weather Statement	RNK	Alleghany	40 min
Aug 17, 6:50 PM EDT	Special Weather Statement	RNK	Watauga	25 min
Aug 17, 7:13 PM EDT	Flash Flood Warning	RNK	Watauga	8 hr
Aug 17, 7:54 PM EDT	Special Weather Statement	RNK	Ashe	36 min

Nearby

Tornado Warnings in North Carolina, 2021 Every tornado warning in 2021 Tornadoes 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.