Alert archive / Virginia / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 7, NWS Baltimore/Washington

February 11, 200910 counties in Virginia

NWS Baltimore/Washington issued this severe thunderstorm warning at Feb 11, 2009, 9:19 PM EST for 10 counties in Virginia. It was in force for 36 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
Feb 11, 2009, 9:19 PM EST (02:19 UTC)
Expired
Feb 11, 2009, 9:55 PM EST
In force
36 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon

Counties Albemarle County, VA, City of Charlottesville, VA, Clarke County, VA, Culpeper County, VA, Fauquier County, VA, Greene County, VA, Loudoun County, VA, Madison County, VA, Orange County, VA, Rappahannock County, VA

The radar

The Sterling radar (KLWX), 76 km from the middle of the area, began a volume at 02:22 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Feb 11, 5:53 PM ESTSevere Thunderstorm WatchSPC4 hr
Feb 11, 8:19 PM ESTSevere Thunderstorm WatchSPC3 hr

The nearest sounding before it

Roanoke, VA (KRNK), launched 00:00Z, 2.3 hours before the alert went out and 189 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 00:00Z on 2009-02-12Temperature 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, Roanoke, VA at 00:00Z on 2009-02-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 414 square meters per square second.1939587897117136Sfc1 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
758 m above ground
0-6 km bulk shear
95 kt
0-1 km storm-relative helicity
414 m²/s²
0-3 km storm-relative helicity
765 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 Baltimore/Washington wrote its last area forecast discussion before this severe thunderstorm warning went out at Feb 11, 8:30 PM EST, 49 minutes earlier.

Area forecast discussion, Feb 11, 8:30 PM EST, 49 minutes before
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Hazardous weather outlook, Feb 11, 6:57 PM EST, 2 hours 22 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
657 PM EST WED FEB 11 2009

ANZ530>537-DCZ001-MDZ006-007-011-013-014-016>018-VAZ052>057-
121000-
CHESAPEAKE BAY NORTH OF POOLES ISLAND MD-
CHESAPEAKE BAY FROM POOLES ISLAND TO SANDY POINT MD-
CHESAPEAKE BAY FROM SANDY POINT TO NORTH BEACH MD-
CHESAPEAKE BAY FROM NORTH BEACH TO DRUM POINT MD-
CHESAPEAKE BAY FROM DRUM POINT MD TO SMITH POINT VA-
TIDAL POTOMAC FROM KEY BRIDGE TO INDIAN HEAD MD-
TIDAL POTOMAC FROM INDIAN HEAD TO COBB ISLAND MD-
TIDAL POTOMAC FROM COBB ISLAND MD TO SMITH POINT VA-
DISTRICT OF COLUMBIA-NORTHERN BALTIMORE-HARFORD-
SOUTHERN BALTIMORE-PRINCE GEORGES-ANNE ARUNDEL-CHARLES-ST. MARYS-
CALVERT-PRINCE WILLIAM/MANASSAS/MANASSAS PARK-FAIRFAX-
ARLINGTON/FALLS CHURCH/ALEXANDRIA-STAFFORD-SPOTSYLVANIA-
KING GEORGE-
657 PM EST WED FEB 11 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE MARYLAND PORTION OF THE
CHESAPEAKE BAY...TIDAL POTOMAC RIVER...AND ADJACENT COUNTIES IN
CENTRAL MARYLAND AND NORTHERN VIRGINIA AS WELL AS THE DISTRICT OF
COLUMBIA.

.DAY ONE...TONIGHT

A SMALL CRAFT ADVISORY IS IN EFFECT THROUGH 10 PM THIS EVENING
FOR THE TIDAL POTOMAC RIVER AND MARYLAND CHESAPEAKE BAY. AFTER 10
PM...A GALE WARNING IS IN EFFECT OVERNIGHT ACROSS THE MARINE
WATERS.

A COLD FRONT WILL MOVE ACROSS THE OUTLOOK AREA TONIGHT. SHOWERS
AND ISOLATED THUNDERSTORMS WILL ACCOMPANY THE FRONT...MOST LIKELY
BETWEEN 10 PM AND 2 AM. THIS ACTIVITY WILL HAVE THE POTENTIAL TO
PRODUCE STRONG GUSTY WINDS.

A WIND ADVISORY HAS BEEN ISSUED STARTING AT 2 AM FOR STRONG GUSTY
WINDS BEHIND THE FRONTAL PASSAGE.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THE WIND ADVISORY WILL CONTINUE THROUGH MIDNIGHT THURSDAY NIGHT.

IN ADDITION...DUE TO LOW RELATIVE HUMIDITIES AND GUSTY WINDS A
FIRE WEATHER WATCH HAS BEEN ISSUED FOR THURSDAY FOR MOST OF THE
AREA.

A GALE WARNING CONTINUES ACROSS THE WATERS THROUGH THURSDAY
EVENING.

A DISTURBANCE WILL TRACK ACROSS THE REGION THIS WEEKEND...BRINGING
THE POTENTIAL FOR WINTRY PRECIPITATION TO THE AREA ON SATURDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS HAVE BEEN ACTIVATED. REPORTS OF WIND GUSTS OR WIND DAMAGE
WOULD BE GREATLY APPRECIATED.

MDZ003>005-009-010-501-502-VAZ021-025>031-036>042-050-051-
WVZ050>055-501>504-121000-
WASHINGTON-FREDERICK MD-CARROLL-MONTGOMERY-HOWARD-
EXTREME WESTERN ALLEGANY-CENTRAL AND EASTERN ALLEGANY-HIGHLAND-
AUGUSTA-ROCKINGHAM-SHENANDOAH-FREDERICK VA-PAGE-WARREN-CLARKE-
NELSON-ALBEMARLE-GREENE-MADISON-RAPPAHANNOCK-FAUQUIER-LOUDOUN-
ORANGE-CULPEPER-HAMPSHIRE-MORGAN-BERKELEY-JEFFERSON-PENDLETON-
HARDY-WESTERN GRANT-EASTERN GRANT-WESTERN MINERAL-EASTERN MINERAL-
657 PM EST WED FEB 11 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN WEST VIRGINIA...
NORTHERN AND CENTRAL VIRGINIA...AND CENTRAL AND WESTERN MARYLAND
WITH THE EXCEPTION OF GARRETT COUNTY.

.DAY ONE...TONIGHT

A SEVERE THUNDERSTORM WATCH HAS BEEN ISSUED FOR THE POTOMAC
HIGHLANDS...SHENANDOAH VALLEY...AND THE CENTRAL FOOTHILLS OF VIRGINIA
UNTIL 10 PM. ANY THUNDERSTORMS THAT BECOME SEVERE WILL HAVE THE
POTENTIAL TO PRODUCE DAMAGING WIND GUSTS.

A COLD FRONT WILL MOVE ACROSS THE OUTLOOK AREA EARLY TONIGHT.
SHOWERS AND ISOLATED THUNDERSTORMS WILL ACCOMPANY THE FRONT...MOST
LIKELY BETWEEN 8 PM AND 1 AM. THIS ACTIVITY WILL HAVE THE
POTENTIAL TO PRODUCE STRONG GUSTY WINDS...A FEW OF WHICH COULD
REACH SEVERE LEVELS UP TO 60 MPH.

A HIGH WIND WARNING HAS BEEN ISSUED FOR STRONG GUSTY WINDS UP TO
60 MPH BEHIND THE FRONTAL PASSAGE STARTING LATER THIS EVENING. THE
WARNING IS IN EFFECT FOR AREAS WEST OF THE BLUE RIDGE IN
VIRGINIA...AS WELL AS LOUDOUN COUNTY...THE EASTERN PANHANDLE OF
WEST VIRGINIA...AND WESTERN MARYLAND INCLUDING FREDERICK COUNTY. A
WIND ADVISORY IS IN EFFECT FOR AREAS EAST OF THIS FOR WINDS
GUSTING UP TO 50 MPH.

A WINTER WEATHER ADVISORY HAS BEEN ISSUED FOR THE FAVORED UPSLOPE
AREAS OF THE ALLEGHENY AND POTOMAC HIGHLANDS STARTING AT 4 AM.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THE HIGH WARNING AND WIND ADVISORY WILL CONTINUE THROUGH MIDNIGHT
THURSDAY NIGHT.

IN ADDITION...DUE TO LOW RELATIVE HUMIDITIES AND GUSTY
WINDS A FIRE WEATHER WATCH HAS BEEN ISSUED FOR THURSDAY FOR MUCH
OF THE AREA.

THE WINTER WEATHER ADVISORY WILL CONTINUE THROUGH 4 PM FOR THE
FAVORED UPSLOPE AREAS OF THE ALLEGHENY AND POTOMAC HIGHLANDS.

A DISTURBANCE WILL TRACK ACROSS THE REGION THIS WEEKEND...BRINGING
THE POTENTIAL FOR WINTRY PRECIPITATION TO THE AREA ON SATURDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS HAVE BEEN ACTIVATED. REPORTS OF SNOW...WIND GUSTS...OR
WIND DAMAGE WOULD BE GREATLY APPRECIATED.

In the hours before

Special weather statement, Feb 11, 7:07 PM EST, 2 hours 12 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
707 PM EST WED FEB 11 2009

VAZ021-WVZ054-120200-
HIGHLAND-PENDLETON-
707 PM EST WED FEB 11 2009

...SEVERE THUNDERSTORM WATCH IN EFFECT THIS EVENING...

A LINE OF FAST MOVING HEAVY SHOWERS AND THUNDERSTORMS WILL RAPIDLY
CROSS HIGHLAND AND PENDLETON COUNTIES BETWEEN 730 AND 815 PM.
THE LINE IS MOVING EAST AT 60 MPH. WINDS WILL GUST FROM THE WEST
BETWEEN 45 AND 65 MPH AS THE LINE MOVES THROUGH. BE PREPARED FOR
TO TAKE SHELTER AFTER 730 PM. HIGH WINDS WILL CONTINUE BEHIND THE
LINE THROUGH THE EVENING WITH FREQUENT WESTERLY GUSTS OVER 50 MPH.

MDZ501-502-WVZ050-055-501>504-120200-
EXTREME WESTERN ALLEGANY-CENTRAL AND EASTERN ALLEGANY-HAMPSHIRE-
HARDY-WESTERN GRANT-EASTERN GRANT-WESTERN MINERAL-EASTERN MINERAL-
INCLUDING THE CITIES OF...FROSTBURG...CUMBERLAND...BAYARD...
PETERSBURG...EMORYVILLE...HARTMANSVILLE...KEYSER...FORT ASHBY
707 PM EST WED FEB 11 2009

...SEVERE THUNDERSTORM WATCH IN EFFECT THIS EVENING...

A LINE OF FAST MOVING HEAVY SHOWERS AND THUNDERSTORMS WILL
RAPIDLY CROSS GRANT...MINERAL AND ALLEGANY COUNTIES BETWEEN 745
AND 815 PM...AND MOVE ACROSS HARDY AND HAMPSHIRE COUNTIES BETWEEN
800 AND 830 PM. THIS LINE IS MOVING EAST AT 60 MPH. WINDS WILL
GUST FROM THE WEST BETWEEN 45 AND 65 MPH AS THE LINE MOVES
THROUGH. HIGH WINDS WILL CONTINUE BEHIND THE LINE THROUGH THE
EVENING WITH FREQUENT WESTERLY GUSTS OVER 50 MPH.

VAZ025>027-029-120200-
AUGUSTA-ROCKINGHAM-SHENANDOAH-PAGE-
INCLUDING THE CITIES OF...STAUNTON...WAYNESBORO...HARRISONBURG
707 PM EST WED FEB 11 2009

...SEVERE THUNDERSTORM WATCH IN EFFECT THIS EVENING...

A LINE OF FAST MOVING HEAVY SHOWERS AND THUNDERSTORMS WILL
RAPIDLY CROSS AUGUSTA AND ROCKINGHAM COUNTIES BETWEEN 815 AND 915
PM...AND THEN ACROSS SHENANDOAH AND PAGE COUNTIES BETWEEN 845 AND
930 PM. THIS LINE IS MOVING EAST AT 60 MPH. WINDS WILL GUST FROM
THE WEST BETWEEN 45 AND 65 MPH AS THE LINE MOVES THROUGH. HIGH
WINDS WILL CONTINUE BEHIND THE LINE THROUGH THE EVENING WITH
FREQUENT WESTERLY GUSTS OVER 50 MPH.

SMZ
Local storm report, Feb 11, 8:38 PM EST, 41 minutes before
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Local storm report, Feb 11, 8:51 PM EST, 28 minutes before
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Local storm report, Feb 11, 8:53 PM EST, 26 minutes before
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Local storm report, Feb 11, 9:06 PM EST, 13 minutes before
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Special weather statement, Feb 11, 9:10 PM EST, 9 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Feb 11, 7:22 PM ESTSevere Thunderstorm WarningLWXAugusta, Highland, Rockingham53 min
Feb 11, 8:10 PM ESTSevere Thunderstorm WarningLWXAlbemarle, Augusta, Greene, Nelson, Rockingham, City of Charlottesville and 3 more65 min
Feb 11, 8:17 PM ESTSevere Thunderstorm WarningLWXAugusta, Frederick, Highland, Rockingham, Shenandoah, City of Winchester58 min
Feb 11, 8:35 PM ESTSevere Thunderstorm WarningLWXFrederick70 min
Feb 11, 8:54 PM ESTSevere Thunderstorm WarningLWXClarke, Frederick, Greene, Madison, Page, Rappahannock and 2 more51 min
Feb 11, 9:33 PM ESTSevere Thunderstorm WarningLWXFairfax, Fauquier, Loudoun, Prince William, Spotsylvania, Stafford and 4 more43 min
Feb 11, 9:37 PM ESTSpecial Marine WarningLWX61 min
Feb 11, 9:51 PM ESTSpecial Marine WarningLWX39 min
Feb 11, 10:07 PM ESTSevere Thunderstorm WarningLWXArlington, Fairfax, City of Alexandria, City of Falls Church49 min
Feb 11, 10:14 PM ESTSpecial Marine WarningLWX44 min
Feb 12, 4:08 AM ESTStorm WarningLWX12 hr
Feb 12, 6:49 AM ESTRed Flag WarningLWXAlbemarle, Arlington, Augusta, Clarke, Culpeper, Fairfax and 19 more14 hr
Feb 11, 7:31 PM ESTSevere Thunderstorm WarningLWXAllegany74 min

Nearby

Severe Thunderstorm Warnings in Virginia, 2009Every severe thunderstorm warning in 2009

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.