Alert archive / Virginia / Tornado Warnings in 2011

Tornado Warning 2, NWS Baltimore/Washington

March 10, 20115 counties in Virginia; Montgomery County, Maryland

NWS Baltimore/Washington issued this tornado warning at Mar 10, 2011, 6:58 PM EST for 5 counties in Virginia; Montgomery County, Maryland. It was in force for 32 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
Mar 10, 2011, 6:58 PM EST (23:58 UTC)
Expired
Mar 10, 2011, 7:30 PM EST
In force
32 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon

Counties Montgomery County, MD, City of Manassas, VA, City of Manassas Park, VA, Fairfax County, VA, Loudoun County, VA, Prince William County, VA

The radar

The Sterling radar (KLWX), 6 km from the middle of the area, began a volume at 00:03 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
Mar 10, 6:59 PM ESTTORNADO1 Wsw Chantilly, VAEF0 TORNADO WITH ESTIMATED 65 MPH WIND. APPROXIMATELY 15 SOFTWOOD TREES SNAPPED ALONG WITH MANY LARGE BRANCHES BROKEN IN A 4.5 MILE PATH WITH A 75 YARD WIDTH. TORNADO ON THE GROUND FOR APPROXIMATELY 4 MINUTES.
Mar 10, 7:00 PM ESTTSTM WND DMG1 Nne Centreville, VA12-20 TREES DOWN NEAR ELEANOR LAWRENCE PARK AND WALNEY ROAD ON VA-28. TIME ESTIMATED.

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.

IssuedProductOfficeLasted
Mar 10, 1:25 PM ESTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 12.0 hours before the alert went out and 10 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 2011-03-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 joules per kilogram.LCLEL10008507005003002001001 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 2011-03-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 462 square meters per square second.1939587897Sfc1 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
1 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
453 m above ground
0-6 km bulk shear
58 kt
0-1 km storm-relative helicity
462 m²/s²
0-3 km storm-relative helicity
658 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

903 
WFUS51 KLWX 102358
TORLWX
MDC031-VAC059-107-153-683-685-110030-
/O.NEW.KLWX.TO.W.0002.110310T2358Z-110311T0030Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
658 PM EST THU MAR 10 2011

THE NATIONAL WEATHER SERVICE IN STERLING VIRGINIA HAS ISSUED A

* TORNADO WARNING FOR...
  WEST CENTRAL MONTGOMERY COUNTY IN CENTRAL MARYLAND...
  NORTHEASTERN CITY OF MANASSAS IN NORTHERN VIRGINIA...
  CITY OF MANASSAS PARK IN NORTHERN VIRGINIA...
  EASTERN LOUDOUN COUNTY IN NORTHERN VIRGINIA...
  NORTH CENTRAL PRINCE WILLIAM COUNTY IN NORTHERN VIRGINIA...
  NORTHWESTERN FAIRFAX COUNTY IN NORTHERN VIRGINIA...

* UNTIL 730 PM EST

* AT 654 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO NEAR
  CENTREVILLE...MOVING NORTH AT 45 MPH.

* LOCATIONS IMPACTED INCLUDE...
  DULLES INTERNATIONAL AIRPORT...
  SOUTH RIDING...
  ARCOLA...
  BROADLANDS...
  HERNDON...
  BRAMBLETON...
  ASHBURN...
  COUNTRYSIDE...
  LANSDOWNE...
  LOWES ISLAND...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING AND AVOID WINDOWS. IF OUTDOORS OR IN A MOBILE HOME OR
VEHICLE...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

THE TORNADO MAY BE WRAPPED IN RAIN AND HARD TO SEE. DO NOT WAIT TO
SEE OR HEAR THE TORNADO. TAKE COVER NOW.

&&

LAT...LON 3922 7757 3918 7719 3875 7741 3876 7755
TIME...MOT...LOC 2358Z 184DEG 37KT 3886 7747

$$
LISTEMAA/SMZ
3 follow-up statements
228 
WWUS51 KLWX 110008
SVSLWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
708 PM EST THU MAR 10 2011

VAC153-683-685-110018-
/O.CAN.KLWX.TO.W.0002.000000T0000Z-110311T0030Z/
CITY OF MANASSAS VA-CITY OF MANASSAS PARK VA-PRINCE WILLIAM VA-
708 PM EST THU MAR 10 2011

...THE TORNADO WARNING IS CANCELLED FOR THE CITY OF MANASSAS...THE
CITY OF MANASSAS PARK...AND NORTH CENTRAL PRINCE WILLIAM COUNTY...

THE THUNDERSTORM THAT PROMPTED THE WARNING HAS EXITED THE WARNED
AREA. THUS THE TORNADO WARNING HAS BEEN CANCELLED.

LAT...LON 3884 7736 3887 7746 3922 7753 3918 7719
TIME...MOT...LOC 0008Z 184DEG 37KT 3894 7741

$$

MDC031-VAC059-107-110030-
/O.CON.KLWX.TO.W.0002.000000T0000Z-110311T0030Z/
MONTGOMERY MD-LOUDOUN VA-FAIRFAX VA-
708 PM EST THU MAR 10 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 730 PM EST FOR
NORTHWESTERN FAIRFAX...EASTERN LOUDOUN AND WEST CENTRAL MONTGOMERY
COUNTIES...

AT 703 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS
TORNADO WAS LOCATED NEAR CHANTILLY...OR NEAR CENTREVILLE...MOVING
NORTH AT 45 MPH.

LOCATIONS IMPACTED INCLUDE...
  STERLING...
  GREAT FALLS...
  COUNTRYSIDE...
  LOWES ISLAND...
  ASHBURN...
  LANSDOWNE...
  DAWSONVILLE...
  DARNESTOWN...
  NORTH POTOMAC...
  POOLESVILLE...
  BEALLSVILLE...
  BOYDS...
  GERMANTOWN...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING AND AVOID WINDOWS. IF OUTDOORS OR IN A MOBILE HOME OR
VEHICLE...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

TORNADOES AT NIGHT ARE DIFFICULT TO SEE AND CONFIRM. TAKE COVER NOW.

&&

LAT...LON 3884 7736 3887 7746 3922 7753 3918 7719
TIME...MOT...LOC 0008Z 184DEG 37KT 3894 7741

$$
LISTEMAA/SMZ
585 
WWUS51 KLWX 110018
SVSLWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
718 PM EST THU MAR 10 2011

MDC031-VAC059-107-110030-
/O.CON.KLWX.TO.W.0002.000000T0000Z-110311T0030Z/
MONTGOMERY MD-LOUDOUN VA-FAIRFAX VA-
718 PM EST THU MAR 10 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 730 PM EST FOR NORTH
CENTRAL FAIRFAX...EXTREME EAST CENTRAL LOUDOUN AND CENTRAL MONTGOMERY
COUNTIES...

AT 717 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS
TORNADO WAS LOCATED NEAR LOWES ISLAND...MOVING NORTH AT 45 MPH.

LOCATIONS IMPACTED INCLUDE...
  DARNESTOWN...
  DAWSONVILLE...
  GAITHERSBURG...
  POOLESVILLE...
  BOYDS...
  GERMANTOWN...
  BEALLSVILLE...
  MONTGOMERY VILLAGE...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING AND AVOID WINDOWS. IF OUTDOORS OR IN A MOBILE HOME OR
VEHICLE...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

TORNADOES AT NIGHT ARE DIFFICULT TO SEE AND CONFIRM. TAKE COVER NOW.

&&

LAT...LON 3894 7731 3896 7736 3921 7744 3918 7719
TIME...MOT...LOC 0018Z 184DEG 37KT 3906 7732

$$
LISTEMAA/SMZ
464 
WWUS51 KLWX 110026
SVSLWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
726 PM EST THU MAR 10 2011

MDC031-VAC059-107-110036-
/O.EXP.KLWX.TO.W.0002.000000T0000Z-110311T0030Z/
MONTGOMERY MD-LOUDOUN VA-FAIRFAX VA-
726 PM EST THU MAR 10 2011

...THE TORNADO WARNING WILL EXPIRE AT 730 PM EST FOR NORTH CENTRAL
FAIRFAX...EXTREME EAST CENTRAL LOUDOUN AND CENTRAL MONTGOMERY
COUNTIES...

THE THUNDERSTORM THAT PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS. THUS THE TORNADO WARNING HAS BEEN ALLOWED TO EXPIRE.

LAT...LON 3894 7731 3896 7736 3921 7744 3918 7719
TIME...MOT...LOC 0026Z 184DEG 37KT 3914 7731

$$
LISTEMAA/SMZ

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 9, 9:26 PM ESTRiver Flood WarningLWXSpotsylvania, Stafford, City of Fredericksburg30 hr
Mar 9, 9:26 PM ESTRiver Flood WarningLWXLoudoun30 hr
Mar 10, 9:46 AM ESTCoastal Flood WarningLWXArlington, Fairfax, King George, Stafford, City of Alexandria, City of Fairfax and 1 more17 hr
Mar 10, 1:06 PM ESTGale WarningLWX8 hr
Mar 10, 1:06 PM ESTSmall Craft AdvisoryLWX37 hr
Mar 10, 2:35 PM ESTFlash Flood WarningLWXAlbemarle, Augusta, Nelson, City of Charlottesville, City of Staunton, City of Waynesboro4 hr
Mar 10, 2:57 PM ESTSpecial Weather StatementLWXAlbemarle, Augusta, Nelson, City of Charlottesville, City of Staunton, City of Waynesboro48 min
Mar 10, 3:04 PM ESTAreal Flood WarningLWXArlington, Fairfax, Prince William, Stafford, City of Alexandria, City of Fairfax and 1 more3 hr
Mar 10, 3:25 PM ESTWinter Weather AdvisoryLWXHighland24 hr
Mar 10, 3:58 PM ESTSpecial Marine WarningLWX92 min
Mar 10, 4:28 PM ESTSpecial Weather StatementLWXCulpeper, Orange, Spotsylvania, Stafford, City of Fredericksburg32 min
Mar 10, 4:34 PM ESTSpecial Weather StatementLWXGreene, Madison, Orange, Page, Rappahannock, City of Charlottesville26 min
Mar 10, 4:36 PM ESTFlash Flood WarningLWXAlbemarle, Culpeper, Fauquier, Greene, King George, Madison and 5 more3 hr
Mar 10, 5:02 PM ESTAreal Flood WarningLWXAugusta, Culpeper, Greene, Madison, Page, Rappahannock and 2 more3 hr
Mar 10, 5:02 PM ESTSevere Thunderstorm WarningLWXCulpeper, Fauquier, Madison, Page, Rappahannock, Warren58 min
Mar 10, 5:18 PM ESTSevere Thunderstorm WarningLWXCulpeper, Fauquier, Madison, Orange, Spotsylvania, Stafford and 1 more57 min
Mar 10, 5:24 PM ESTSpecial Weather StatementLWXClarke, Frederick, City of Winchester36 min
Mar 10, 5:26 PM ESTAreal Flood WarningLWXClarke, Frederick, Page, Shenandoah, Warren, City of Winchester3 hr
Mar 10, 5:28 PM ESTSpecial Marine WarningLWX92 min
Mar 10, 5:34 PM ESTSevere Thunderstorm WarningLWXClarke, Fauquier, Frederick, Loudoun, Warren, City of Winchester41 min
Mar 10, 5:48 PM ESTFlash Flood WarningLWXArlington, Fairfax, Fauquier, King George, Loudoun, Prince William and 6 more4 hr
Mar 10, 6:04 PM ESTSpecial Weather StatementLWXFauquier, Prince William, City of Manassas26 min
Mar 10, 6:07 PM ESTFlash Flood WarningLWXLoudoun3 hr
Mar 10, 6:10 PM ESTSevere Thunderstorm WarningLWXCulpeper, Fairfax, Fauquier, King George, Loudoun, Orange and 7 more65 min
Mar 10, 6:14 PM ESTTornado WarningLWXFauquier, Prince William31 min
Mar 10, 6:20 PM ESTSpecial Weather StatementLWXLoudoun25 min
Mar 10, 6:38 PM ESTAreal Flood WarningLWXFrederick3 hr
Mar 10, 12:37 PM ESTAreal Flood WarningLWXAnne Arundel, Baltimore, Harford, Howard, City of Baltimore6 hr
Mar 10, 2:46 PM ESTRiver Flood WarningLWXMontgomery13 hr
Mar 10, 4:06 PM ESTAreal Flood WarningLWXAnne Arundel, Montgomery, Prince George's4 hr
Mar 10, 6:06 PM ESTSpecial Weather StatementLWXWashington24 min
Mar 10, 6:29 PM ESTFlash Flood WarningLWXAnne Arundel, Baltimore, Carroll, Frederick, Harford, Howard and 2 more4 hr

Nearby

Tornado Warnings in Virginia, 2011Tornado Warnings in Maryland, 2011Every tornado warning in 2011Tornadoes in 2011

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.