Alert archive / Virginia / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 105, NWS Blacksburg, VA

July 21, 2020Carroll County, Virginia

NWS Blacksburg, VA issued this severe thunderstorm warning at Jul 21, 2020, 1:29 PM EDT for Carroll County, Virginia. It was in force for 61 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 21, 2020, 1:29 PM EDT (17:29 UTC)
Expired
Jul 21, 2020, 2:30 PM EDT
In force
61 min
Issued by
NWS Blacksburg, VA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Carroll County, VA

The radar

The Roanoke radar (KFCX), 52 km from the middle of the area, began a volume at 17:32 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 5.5 hours before the alert went out and 383 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, Washington/Dulle, VA at 12:00Z on 2020-07-21Temperature 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, Washington/Dulle, VA at 12:00Z on 2020-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 4 square meters per square second.1939Sfc1 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
1997 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
4 m²/s²
0-3 km storm-relative helicity
67 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Blacksburg, VA wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 21, 1:17 PM EDT, 12 minutes earlier.

Area forecast discussion, Jul 21, 1:17 PM EDT, 12 minutes before
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Hazardous weather outlook, Jul 21, 4:05 AM EDT, 9 hours 24 minutes before
Hazardous Weather Outlook
National Weather Service Blacksburg VA
405 AM EDT Tue Jul 21 2020

NCZ005-006-VAZ044>047-058-059-220900-
Rockingham-Caswell-Pittsylvania-Campbell-Appomattox-Buckingham-
Halifax-Charlotte-
405 AM EDT Tue Jul 21 2020

...HEAT ADVISORY IN EFFECT FROM NOON TODAY TO 8 PM EDT THIS
EVENING...

This Hazardous Weather Outlook is for north central North Carolina,
central Virginia and south central Virginia.

.DAY ONE...Today and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Heat Advisory.

There is also a Marginal Risk for strong to severe thunderstorms
this afternoon and evening. The primary threat will be damaging wind
gusts.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Heat index values may reach 102 to 108 again on Wednesday.

Thunderstorms could be strong to severe Wednesday afternoon and
evening, with damaging winds the main threat.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

NCZ003-004-019-020-VAZ022>024-032>035-043-220900-
Surry-Stokes-Wilkes-Yadkin-Roanoke-Botetourt-Rockbridge-Patrick-
Franklin-Bedford-Amherst-Henry-
405 AM EDT Tue Jul 21 2020

This Hazardous Weather Outlook is for north central North Carolina,
northwest North Carolina, central Virginia, south central Virginia,
southwest Virginia and west central Virginia.

.DAY ONE...Today and tonight.

There is a Marginal Risk for strong to severe thunderstorms this
afternoon and evening. The primary threat will be damaging wind
gusts. Also, heat index values may reach 100-104 this afternoon.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Thunderstorms could be strong to severe Wednesday afternoon and
evening, with damaging winds the main threat.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

NCZ001-002-018-VAZ007-009>020-WVZ042>044-507-508-220900-
Ashe-Alleghany NC-Watauga-Tazewell-Smyth-Bland-Giles-Wythe-Pulaski-
Montgomery-Grayson-Carroll-Floyd-Craig-Alleghany VA-Bath-Mercer-
Summers-Monroe-Eastern Greenbrier-Western Greenbrier-
405 AM EDT Tue Jul 21 2020

This Hazardous Weather Outlook is for northwest North Carolina,
southwest Virginia, west central Virginia and southeast West
Virginia.

.DAY ONE...Today and tonight.

There is a Marginal Risk for strong to severe thunderstorms this
afternoon and evening. The primary threat will be damaging wind
gusts.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Thunderstorms could be strong to severe Wednesday afternoon and
evening, with damaging winds the main threat.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

In the hours before

Special weather statement, Jul 21, 12:19 PM EDT, 1 hour 10 minutes before
Special Weather Statement
National Weather Service BLACKSBURG VA
1219 PM EDT Tue Jul 21 2020

VAZ015-211645-
Grayson-
1219 PM EDT Tue Jul 21 2020

...A STRONG THUNDERSTORM WILL AFFECT
NORTHEASTERN GRAYSON COUNTY...

At 1219 PM EDT, a strong thunderstorm was located over Spring Valley,
or near Fries, moving east at 5 mph.

Winds in excess of 30 mph and pea size hail are possible with this
storm.

Locations impacted include...
Fries...
and Spring Valley.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

LAT...LON 3676 8101 3675 8099 3665 8095 3663 8112
      3671 8115
TIME...MOT...LOC 1619Z 264DEG 5KT 3669 8107

RR
Special weather statement, Jul 21, 12:50 PM EDT, 39 minutes before
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Special weather statement, Jul 21, 1:16 PM EDT, 13 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Jul 20, 9:38 PM EDTHeat AdvisoryRNKAppomattox, Buckingham, Campbell, Charlotte, Halifax, Pittsylvania and 2 more22 hr
Jul 20, 10:08 PM EDTSpecial Weather StatementRNKSmyth37 min
Jul 21, 12:19 PM EDTSpecial Weather StatementRNKCity of Galax26 min
Jul 21, 12:50 PM EDTSpecial Weather StatementRNKPulaski25 min
Jul 21, 1:16 PM EDTSpecial Weather StatementRNKPulaski, City of Radford29 min
Jul 21, 1:39 PM EDTSpecial Weather StatementRNKCity of Salem36 min
Jul 21, 1:41 PM EDTSpecial Weather StatementRNKCity of Galax34 min
Jul 21, 1:45 PM EDTSpecial Weather StatementRNKMontgomery30 min
Jul 21, 2:15 PM EDTSpecial Weather StatementRNKFloyd30 min
Jul 21, 2:43 PM EDTSpecial Weather StatementRNKFloyd32 min
Jul 21, 2:49 PM EDTSevere Thunderstorm WarningRNKFloyd41 min
Jul 21, 2:57 PM EDTSpecial Weather StatementRNKCraig33 min
Jul 21, 3:05 PM EDTSevere Thunderstorm WarningRNKBotetourt, Craig40 min
Jul 21, 3:13 PM EDTSpecial Weather StatementRNKCity of Roanoke32 min
Jul 21, 3:22 PM EDTSevere Thunderstorm WarningRNKBedford, Botetourt, Franklin, Roanoke, City of Roanoke38 min
Jul 21, 3:44 PM EDTSpecial Weather StatementRNKRockbridge, City of Lexington31 min
Jul 21, 4:03 PM EDTSevere Thunderstorm WarningRNKBedford, Campbell, City of Lynchburg57 min
Jul 21, 4:35 PM EDTSpecial Weather StatementRNKBath25 min
Jul 21, 6:34 PM EDTSpecial Weather StatementRNKBland41 min
Jul 21, 7:22 PM EDTSpecial Weather StatementRNKHalifax23 min
Jul 21, 3:36 PM EDTSpecial Weather StatementRNKAlleghany, Ashe, Watauga24 min
Jul 21, 4:17 PM EDTSpecial Weather StatementRNKWatauga28 min
Jul 21, 4:47 PM EDTSpecial Weather StatementRNKWilkes28 min
Jul 21, 5:16 PM EDTSpecial Weather StatementRNKWilkes29 min

Nearby

Severe Thunderstorm Warnings in Virginia, 2020Every severe thunderstorm warning in 2020

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.