Alert archive / Virginia / Tornado Warnings in 2012

Tornado Warning 39, NWS Baltimore/Washington

September 8, 20124 counties in Virginia

NWS Baltimore/Washington issued this tornado warning at Sep 8, 2012, 3:44 PM EDT for 4 counties in Virginia. It was in force for 15 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
Sep 8, 2012, 3:44 PM EDT (19:44 UTC)
Expired
Sep 8, 2012, 3:59 PM EDT
In force
15 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon

Counties Arlington County, VA, City of Alexandria, VA, City of Falls Church, VA, Fairfax County, VA

The radar

The Sterling radar (KLWX), 36 km from the middle of the area, began a volume at 19:47 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
Sep 8, 3:58 PM EDTTSTM WND DMG1 Nnw Alexandria, VATREE DOWN AT I-395 AND KING STREET
Sep 8, 4:00 PM EDTTSTM WND DMG1 Wnw Reagan National A, VA3 FT DIAMETER TREE 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.

IssuedProductOfficeLasted
Sep 8, 12:15 PM EDTSevere Thunderstorm WatchSPC9 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 7.7 hours before the alert went out and 28 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 2012-09-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 252 joules per kilogram.LCLLFCEL10008507005003002001001 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 2012-09-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 150 square meters per square second.193958Sfc1 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
252 J/kg
Mixed-layer CIN
-81 J/kg
Mixed-layer LCL
638 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
150 m²/s²
0-3 km storm-relative helicity
140 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.0

Open this sounding in Storm Lab

The text

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

359 
WFUS51 KLWX 081944
TORLWX
VAC013-059-510-610-082015-
/O.NEW.KLWX.TO.W.0039.120908T1944Z-120908T2015Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
344 PM EDT SAT SEP 8 2012

THE NATIONAL WEATHER SERVICE IN STERLING VIRGINIA HAS ISSUED A

* TORNADO WARNING FOR...
  CITY OF FALLS CHURCH IN NORTHERN VIRGINIA...
  SOUTHERN ARLINGTON COUNTY IN NORTHERN VIRGINIA...
  CITY OF ALEXANDRIA IN NORTHERN VIRGINIA...
  EASTERN FAIRFAX COUNTY IN NORTHERN VIRGINIA...

* UNTIL 415 PM EDT

* AT 343 PM EDT...A CONFIRMED TORNADO WAS REPORTED NEAR FAIRFAX...
  AND WAS MOVING EAST AT 50 MPH. THIS TORNADO HAS BEEN CONFIRMED BY
  COUNTY OFFICIALS.

* LOCATIONS IMPACTED INCLUDE...
  ALEXANDRIA...
  HUNTINGTON...
  CRYSTAL CITY...
  BALLSTON...
  THE WOODROW WILSON BRIDGE...
  REAGAN NATIONAL AIRPORT...

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.

MOTORISTS SHOULD NOT TAKE SHELTER UNDER HIGHWAY OVERPASSES. AS A LAST
RESORT...EITHER PARK AND STAY IN YOUR VEHICLE...OR ABANDON YOUR
VEHICLE AND LAY FLAT IN A LOW SPOT.

THIS TORNADO MAY BE WRAPPED IN RAIN AND HARD TO SEE. TAKE COVER NOW.

&&

LAT...LON 3878 7704 3882 7724 3888 7722 3889 7721
      3890 7707 3888 7705 3886 7703 3879 7703
TIME...MOT...LOC 1944Z 283DEG 43KT 3885 7718

$$

GMS
2 follow-up statements
360 
WWUS51 KLWX 081951
SVSLWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
351 PM EDT SAT SEP 8 2012

VAC013-059-510-610-082015-
/O.CON.KLWX.TO.W.0039.000000T0000Z-120908T2015Z/
CITY OF FALLS CHURCH VA-ARLINGTON VA-CITY OF ALEXANDRIA VA-FAIRFAX VA-
351 PM EDT SAT SEP 8 2012

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 415 PM EDT FOR THE CITY
OF ALEXANDRIA...THE CITY OF FALLS CHURCH...AND FAIRFAX AND ARLINGTON
COUNTIES...

AT 350 PM EDT...A SEVERE THUNDERSTORM WITH A HISTORY OF PRODUCING 
TORNADOES WAS LOCATED OVER ARLINGTON...NEAR BAILEYS CROSSROADS...AND 
WAS MOVING EAST AT 50 MPH.

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.

MOTORISTS SHOULD NOT TAKE SHELTER UNDER HIGHWAY OVERPASSES. AS A LAST
RESORT...EITHER PARK AND STAY IN YOUR VEHICLE...OR ABANDON YOUR
VEHICLE AND LAY FLAT IN A LOW SPOT.

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

&&

LAT...LON 3885 7703 3880 7703 3884 7718 3889 7717
      3890 7707 3889 7706 3888 7707 3886 7703
TIME...MOT...LOC 1951Z 280DEG 41KT 3886 7708

$$

GMS
140 
WWUS51 KLWX 081959
SVSLWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
359 PM EDT SAT SEP 8 2012

VAC013-059-510-610-082009-
/O.CAN.KLWX.TO.W.0039.000000T0000Z-120908T2015Z/
CITY OF FALLS CHURCH VA-ARLINGTON VA-CITY OF ALEXANDRIA VA-FAIRFAX VA-
359 PM EDT SAT SEP 8 2012

...THE TORNADO WARNING IS CANCELLED FOR THE CITY OF ALEXANDRIA...THE
CITY OF FALLS CHURCH...AND FAIRFAX AND ARLINGTON COUNTIES...

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

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR THE WARNED AREA.

LAT...LON 3885 7703 3880 7703 3884 7718 3889 7717
      3890 7707 3889 7706 3888 7707 3886 7703
TIME...MOT...LOC 1959Z 280DEG 41KT 3884 7697

$$

GMS

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 7, 10:42 PM EDTSmall Craft AdvisoryLWX23 hr
Sep 8, 11:51 AM EDTSpecial Weather StatementLWXFrederick24 min
Sep 8, 12:02 PM EDTSevere Thunderstorm WarningLWXClarke, Frederick, City of Winchester43 min
Sep 8, 12:43 PM EDTSpecial Weather StatementLWXClarke, Frederick, City of Winchester47 min
Sep 8, 1:22 PM EDTSpecial Weather StatementLWXClarke23 min
Sep 8, 1:49 PM EDTSpecial Weather StatementLWXLoudoun26 min
Sep 8, 1:52 PM EDTSpecial Weather StatementLWXClarke, Shenandoah, City of Winchester23 min
Sep 8, 2:04 PM EDTSpecial Weather StatementLWXAugusta26 min
Sep 8, 2:16 PM EDTSevere Thunderstorm WarningLWXClarke, Frederick, Page, Rockingham, Shenandoah, Warren and 1 more46 min
Sep 8, 2:19 PM EDTSpecial Weather StatementLWXLoudoun26 min
Sep 8, 2:28 PM EDTTornado WarningLWXFrederick, Shenandoah, Warren20 min
Sep 8, 2:32 PM EDTSpecial Weather StatementLWXAugusta, Rockingham, City of Harrisonburg, City of Staunton, City of Waynesboro28 min
Sep 8, 2:47 PM EDTSevere Thunderstorm WarningLWXClarke, Culpeper, Fauquier, Loudoun, Madison, Page and 3 more58 min
Sep 8, 2:51 PM EDTSpecial Weather StatementLWXCulpeper, Greene, Madison39 min
Sep 8, 3:10 PM EDTSpecial Marine WarningLWX2 hr
Sep 8, 3:16 PM EDTSevere Thunderstorm WarningLWXAlbemarle, City of Charlottesville32 min
Sep 8, 3:17 PM EDTSpecial Weather StatementLWXGreene, Madison, Nelson, City of Waynesboro28 min
Sep 8, 3:18 PM EDTSpecial Weather StatementLWXArlington, Fairfax, City of Alexandria, City of Fairfax, City of Falls Church, City of Manassas and 1 more87 min
Sep 8, 3:22 PM EDTSpecial Marine WarningLWX98 min
Sep 8, 3:22 PM EDTSevere Thunderstorm WarningLWXArlington, Culpeper, Fairfax, Fauquier, Loudoun, Prince William and 6 more68 min
Sep 8, 3:29 PM EDTTornado WarningLWXFairfax, City of Fairfax20 min
Sep 8, 3:55 PM EDTSpecial Weather StatementLWXAlbemarle, Culpeper, Madison, Nelson, Orange, Spotsylvania and 3 more80 min
Sep 8, 3:58 PM EDTSevere Thunderstorm WarningLWXArlington, Fairfax, Prince William, Stafford, City of Alexandria, City of Falls Church55 min
Sep 8, 4:06 PM EDTSevere Thunderstorm WarningLWXCulpeper, Fauquier, Orange, Spotsylvania, Stafford, City of Fredericksburg39 min
Sep 8, 4:20 PM EDTSpecial Marine WarningLWX85 min
Sep 8, 4:47 PM EDTSpecial Weather StatementLWXKing George, Spotsylvania, Stafford, City of Fredericksburg28 min
Sep 8, 4:56 PM EDTSpecial Marine WarningLWX72 min
Sep 8, 5:41 PM EDTSpecial Marine WarningLWX67 min
Sep 8, 5:58 PM EDTSpecial Marine WarningLWX83 min

Nearby

Tornado Warnings in Virginia, 2012Every tornado warning in 2012Tornadoes in 2012

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.