Alert archive / Virginia / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 252, NWS Baltimore/Washington

July 31, 2012Augusta County, Virginia

NWS Baltimore/Washington issued this severe thunderstorm warning at Jul 31, 2012, 7:51 PM EDT for Augusta County, Virginia. It was in force for 39 min. 1 report 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
Jul 31, 2012, 7:51 PM EDT (23:51 UTC)
Expired
Jul 31, 2012, 8:30 PM EDT
In force
39 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon

County Augusta County, VA

The radar

The Roanoke radar (KFCX), 166 km from the middle of the area, began a volume at 23:54 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
Jul 31, 7:51 PM EDTTSTM WND DMG3 Ne Augusta Springs, VATREE DOWN AT THE 800 BLOCK OF LITTLE CALF PASTURE HIGHWAY DUE TO STRONG THUNDERSTORM WINDS.

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

The nearest sounding before it

Roanoke, VA (KRNK), launched 12:00Z, 11.9 hours before the alert went out and 119 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, Roanoke, VA at 12:00Z on 2012-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 384 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, Roanoke, VA at 12:00Z on 2012-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 7 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
384 J/kg
Mixed-layer CIN
-68 J/kg
Mixed-layer LCL
804 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
36 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.

639 
WUUS51 KLWX 312351
SVRLWX
VAC015-010030-
/O.NEW.KLWX.SV.W.0252.120731T2351Z-120801T0030Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
751 PM EDT TUE JUL 31 2012

THE NATIONAL WEATHER SERVICE IN STERLING VIRGINIA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN AUGUSTA COUNTY IN WESTERN VIRGINIA...

* UNTIL 830 PM EDT

* AT 747 PM EDT...A SEVERE THUNDERSTORM WAS DETECTED 5 MILES
  SOUTHWEST OF BUFFALO GAP...AND WAS MOVING NORTHEAST AT 20 MPH. THIS
  STORM IS CAPABLE OF PRODUCING HAIL UP TO THE SIZE OF QUARTERS AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.

* LOCATIONS IMPACTED INCLUDE...
  BUFFALO GAP...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...MOVE INDOORS TO A
STURDY BUILDING AND STAY AWAY FROM WINDOWS. WHEN IT IS SAFE TO DO
SO...REPORT SEVERE WEATHER TO LOCAL LAW ENFORCEMENT OR TO THE
NATIONAL WEATHER SERVICE.

LAT...LON 3839 7917 3827 7897 3805 7928 3812 7937
TIME...MOT...LOC 2351Z 221DEG 18KT 3814 7928

$$


HTS
2 follow-up statements
602 
WWUS51 KLWX 010013
SVSLWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
813 PM EDT TUE JUL 31 2012

VAC015-010030-
/O.CON.KLWX.SV.W.0252.000000T0000Z-120801T0030Z/
AUGUSTA VA-
813 PM EDT TUE JUL 31 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM EDT
FOR AUGUSTA COUNTY...

AT 808 PM EDT...A SEVERE THUNDERSTORM WAS DETECTED NEAR BUFFALO
GAP...AND WAS MOVING NORTHEAST AT 20 MPH.

THIS STORM IS CAPABLE OF PRODUCING HAIL UP TO THE SIZE OF QUARTERS
AND DAMAGING WINDS IN EXCESS OF 60 MPH.

LOCATIONS IMPACTED INCLUDE...
  CHURCHVILLE...
  MOSCOW...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...MOVE INDOORS TO A
STURDY BUILDING AND STAY AWAY FROM WINDOWS. WHEN IT IS SAFE TO DO
SO...REPORT SEVERE WEATHER TO LOCAL LAW ENFORCEMENT OR TO THE
NATIONAL WEATHER SERVICE.

LAT...LON 3808 7924 3815 7934 3839 7917 3827 7897
TIME...MOT...LOC 0013Z 221DEG 16KT 3820 7921

$$


HTS
615 
WWUS51 KLWX 010024
SVSLWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
824 PM EDT TUE JUL 31 2012

VAC015-010034-
/O.EXP.KLWX.SV.W.0252.000000T0000Z-120801T0030Z/
AUGUSTA VA-
824 PM EDT TUE JUL 31 2012

...THE SEVERE THUNDERSTORM WARNING WILL EXPIRE AT 830 PM EDT FOR
AUGUSTA COUNTY...

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

LAT...LON 3808 7924 3815 7934 3839 7917 3828 7896
TIME...MOT...LOC 0024Z 221DEG 16KT 3824 7917

$$


HTS

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 30, 8:03 PM EDTSpecial Weather StatementLWXHighland27 min
Jul 30, 8:27 PM EDTCoastal Flood AdvisoryLWXArlington, City of Alexandria, City of Falls Church13 hr
Jul 31, 3:50 AM EDTSpecial Marine WarningLWX85 min
Jul 31, 3:01 PM EDTSevere Thunderstorm WarningLWXFrederick29 min
Jul 31, 3:20 PM EDTSpecial Weather StatementLWXCity of Winchester40 min
Jul 31, 5:04 PM EDTSevere Thunderstorm WarningLWXLoudoun20 min
Jul 31, 5:27 PM EDTSpecial Weather StatementLWXFairfax, Prince William, City of Fairfax, City of Manassas, City of Manassas Park33 min
Jul 31, 5:45 PM EDTSevere Thunderstorm WarningLWXFairfax, City of Fairfax45 min
Jul 31, 6:03 PM EDTSpecial Weather StatementLWXCity of Charlottesville42 min
Jul 31, 6:23 PM EDTSpecial Marine WarningLWX44 min
Jul 31, 6:28 PM EDTSpecial Marine WarningLWX38 min
Jul 31, 6:47 PM EDTSpecial Weather StatementLWXOrange28 min
Jul 31, 6:48 PM EDTSpecial Weather StatementLWXFauquier42 min
Jul 31, 6:56 PM EDTSevere Thunderstorm WarningLWXCulpeper, Fauquier49 min
Jul 31, 7:12 PM EDTSpecial Weather StatementLWXOrange33 min
Jul 31, 7:20 PM EDTSpecial Weather StatementLWXGreene25 min
Jul 31, 7:29 PM EDTSpecial Weather StatementLWXShenandoah61 min
Jul 31, 7:36 PM EDTSpecial Weather StatementLWXCulpeper39 min
Jul 31, 7:45 PM EDTSpecial Weather StatementLWXAugusta45 min
Jul 31, 7:54 PM EDTSpecial Weather StatementLWXPage51 min

Nearby

Severe Thunderstorm Warnings in Virginia, 2012Every severe thunderstorm warning 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.