Alert archive / Virginia / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 331, NWS Baltimore/Washington

August 10, 20214 counties in Virginia

NWS Baltimore/Washington issued this severe thunderstorm warning at Aug 10, 2021, 4:42 PM EDT for 4 counties in Virginia. It was in force for 48 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 10, 2021, 4:42 PM EDT (20:42 UTC)
Expired
Aug 10, 2021, 5:30 PM EDT
In force
48 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Culpeper County, VA, Fauquier County, VA, Madison County, VA, Rappahannock County, VA

The radar

The Sterling radar (KLWX), 62 km from the middle of the area, began a volume at 20:43 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

TimeReportWhereRemark
Aug 10, 5:00 PM EDTTSTM WND DMG2 Ne Etlan, VAABOUT A DOZEN TREES BLEW DOWN ALONG VA-231 F T VALLEY ROAD AND NETHERS ROAD.
Aug 10, 5:04 PM EDTTSTM WND DMG2 Nw Hackleys Crossroad, VASEVERAL TREES BLEW DOWN ALONG GRIMSLEY ROAD.

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

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.7 hours before the alert went out and 68 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 2021-08-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 529 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, Washington/Dulle, VA at 12:00Z on 2021-08-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 37 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
529 J/kg
Mixed-layer CIN
-120 J/kg
Mixed-layer LCL
1096 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
37 m²/s²
0-3 km storm-relative helicity
65 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

826 
WUUS51 KLWX 102042
SVRLWX
VAC047-061-113-157-102130-
/O.NEW.KLWX.SV.W.0331.210810T2042Z-210810T2130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Baltimore MD/Washington DC
442 PM EDT Tue Aug 10 2021

The National Weather Service in Sterling Virginia has issued a

* Severe Thunderstorm Warning for...
  Northeastern Madison County in northwestern Virginia...
  Rappahannock County in northwestern Virginia...
  West central Fauquier County in northern Virginia...
  West central Culpeper County in northern Virginia...

* Until 530 PM EDT.

* At 441 PM EDT, severe thunderstorms were located along a line
  extending from 8 miles south of Front Royal to near Sperryville,
  moving east at 15 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Damaging winds will cause some trees and large branches 
           to fall. This could injure those outdoors, as well as 
           damage homes and vehicles. Roadways may become blocked by 
           downed trees. Localized power outages are possible. 
           Unsecured light objects may become projectiles.

* Locations impacted include...
  Sperryville, Hume, Chester Gap, Flint Hill, Washington, Castleton,
  Huntly, Slate Mills, Etlan, Nethers, Woodville, Hackleys
  Crossroads, Cresthill, Five Forks, Rock Mills, Reva and Boston.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3885 7796 3846 7813 3855 7837 3877 7823
      3878 7819 3883 7817 3887 7813
TIME...MOT...LOC 2041Z 265DEG 12KT 3880 7821 3860 7829 

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

$$

DHOF
3 follow-up statements
216 
WWUS51 KLWX 102052
SVSLWX

Severe Weather Statement
National Weather Service Baltimore MD/Washington DC
452 PM EDT Tue Aug 10 2021

VAC047-061-113-157-102130-
/O.CON.KLWX.SV.W.0331.000000T0000Z-210810T2130Z/
Madison VA-Rappahannock VA-Fauquier VA-Culpeper VA-
452 PM EDT Tue Aug 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM EDT
FOR NORTHEASTERN MADISON...RAPPAHANNOCK...WEST CENTRAL FAUQUIER AND
WEST CENTRAL CULPEPER COUNTIES...

At 452 PM EDT, severe thunderstorms were located along a line
extending from 8 miles south of Front Royal to near Sperryville,
moving east at 15 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Damaging winds will cause some trees and large branches to 
         fall. This could injure those outdoors, as well as damage 
         homes and vehicles. Roadways may become blocked by downed 
         trees. Localized power outages are possible. Unsecured 
         light objects may become projectiles.

Locations impacted include...
Sperryville, Hume, Chester Gap, Flint Hill, Washington, Castleton,
Huntly, Slate Mills, Etlan, Nethers, Woodville, Hackleys Crossroads,
Cresthill, Five Forks, Rock Mills, Reva and Boston.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3885 7796 3846 7813 3854 7836 3876 7821
      3878 7819 3883 7817 3887 7813
TIME...MOT...LOC 2052Z 265DEG 12KT 3880 7818 3860 7826 

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

$$

DHOF
128 
WWUS51 KLWX 102110
SVSLWX

Severe Weather Statement
National Weather Service Baltimore MD/Washington DC
510 PM EDT Tue Aug 10 2021

VAC113-102119-
/O.CAN.KLWX.SV.W.0331.000000T0000Z-210810T2130Z/
Madison VA-
510 PM EDT Tue Aug 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN MADISON COUNTY IS
CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

LAT...LON 3885 7796 3846 7813 3855 7825 3887 7809
TIME...MOT...LOC 2109Z 265DEG 12KT 3880 7812 3860 7820 

$$

VAC047-061-157-102130-
/O.CON.KLWX.SV.W.0331.000000T0000Z-210810T2130Z/
Rappahannock VA-Fauquier VA-Culpeper VA-
510 PM EDT Tue Aug 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM EDT
FOR CENTRAL RAPPAHANNOCK...WEST CENTRAL FAUQUIER AND WEST CENTRAL
CULPEPER COUNTIES...

At 509 PM EDT, severe thunderstorms were located along a line
extending from 6 miles west of Hume to near Sperryville, moving east
at 15 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Damaging winds will cause some trees and large branches to 
         fall. This could injure those outdoors, as well as damage 
         homes and vehicles. Roadways may become blocked by downed 
         trees. Localized power outages are possible. Unsecured 
         light objects may become projectiles.

Locations impacted include...
Hume, Flint Hill, Washington, Castleton, Slate Mills, Woodville,
Hackleys Crossroads, Cresthill, Five Forks, Rock Mills, Reva, Boston
and Huntly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3885 7796 3846 7813 3855 7825 3887 7809
TIME...MOT...LOC 2109Z 265DEG 12KT 3880 7812 3860 7820 

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

$$

DHOF
845 
WWUS51 KLWX 102121
SVSLWX

Severe Weather Statement
National Weather Service Baltimore MD/Washington DC
521 PM EDT Tue Aug 10 2021

VAC047-061-157-102131-
/O.EXP.KLWX.SV.W.0331.000000T0000Z-210810T2130Z/
Rappahannock VA-Fauquier VA-Culpeper VA-
521 PM EDT Tue Aug 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL RAPPAHANNOCK...WEST
CENTRAL FAUQUIER AND WEST CENTRAL CULPEPER COUNTIES WILL EXPIRE AT
530 PM EDT...
    
The storms which prompted the warning have weakened below severe
limits, and have exited the warned area. Therefore, the warning will
be allowed to expire.

LAT...LON 3885 7796 3846 7813 3855 7825 3887 7809
TIME...MOT...LOC 2121Z 270DEG 12KT 3880 7807 3860 7815 

$$

CJL

The office that day

Everything else NWS Baltimore/Washington issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 10, 1:33 PM EDTExcessive Heat WatchLWXArlington, Clarke, Fairfax, Fauquier, King George, Loudoun and 6 more37 hr
Aug 10, 1:33 PM EDTHeat AdvisoryLWXArlington, Clarke, Fairfax, Fauquier, King George, Loudoun and 6 more29 hr
Aug 10, 2:30 PM EDTSevere Thunderstorm WarningLWXCulpeper, Fauquier, Rappahannock45 min
Aug 10, 2:44 PM EDTSevere Thunderstorm WarningLWXAlbemarle, City of Charlottesville23 min
Aug 10, 3:24 PM EDTSevere Thunderstorm WarningLWXOrange34 min
Aug 10, 4:15 PM EDTSevere Thunderstorm WarningLWXFairfax, Prince William, City of Manassas, City of Manassas Park31 min
Aug 10, 4:34 PM EDTSevere Thunderstorm WarningLWXFairfax, Loudoun41 min
Aug 10, 4:44 PM EDTSevere Thunderstorm WarningLWXFauquier19 min
Aug 10, 5:05 PM EDTSevere Thunderstorm WarningLWXNelson40 min
Aug 10, 5:08 PM EDTSevere Thunderstorm WarningLWXFairfax18 min
Aug 10, 5:09 PM EDTSpecial Marine WarningLWX96 min
Aug 10, 5:12 PM EDTSevere Thunderstorm WarningLWXArlington, Fairfax, City of Alexandria, City of Fairfax, City of Falls Church48 min
Aug 10, 5:16 PM EDTSevere Thunderstorm WarningLWXClarke, Fauquier, Loudoun44 min
Aug 10, 5:41 PM EDTSevere Thunderstorm Warning Considerable damage threatLWXFairfax, Fauquier, Loudoun, Prince William35 min
Aug 10, 5:53 PM EDTSevere Thunderstorm WarningLWXArlington, Fairfax, City of Alexandria29 min
Aug 10, 6:31 PM EDTSpecial Marine WarningLWX64 min
Aug 10, 6:35 PM EDTSpecial Marine WarningLWX85 min
Aug 10, 6:50 PM EDTSpecial Marine WarningLWX85 min
Aug 10, 6:53 PM EDTSpecial Marine WarningLWX69 min
Aug 10, 7:32 PM EDTSpecial Marine WarningLWX88 min

Nearby

Severe Thunderstorm Warnings in Virginia, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.