Alert archive / Virginia / Tornado Warnings in 2011

Tornado Warning 35, NWS Baltimore/Washington

April 27, 20114 counties in Virginia

NWS Baltimore/Washington issued this tornado warning at Apr 27, 2011, 10:28 PM EDT for 4 counties in Virginia. It was in force for 47 min. 5 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: Apr 27, 2011, 10:28 PM EDT (02:28 UTC)
Expired: Apr 27, 2011, 11:15 PM EDT
In force: 47 min
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon

Counties City of Manassas, VA, City of Manassas Park, VA, Fauquier County, VA, Prince William County, VA

The radar

The Sterling radar (KLWX), 25 km from the middle of the area, began a volume at 02:29 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

Time	Report	Where	Remark
Apr 27, 10:42 PM EDT	FUNNEL CLOUD	2 Wsw Nokesville, VA	RELAYED TO 911 DISPATCH THAT A FUNNEL CLOUD WAS REPORTED NEAR INTERSECTION OF RT 28 AND PRINCE WILLIAM COUNTY PARKWAY
Apr 27, 10:45 PM EDT	TSTM WND DMG	1 Sse Nokesville, VA	TREE BLOWN ONTO POWER LINES CAUSING SPARKS
Apr 27, 10:45 PM EDT	TSTM WND DMG	3 Ne Nokesville, VA	INSIDE CEILING PANELS WERE BLOWN OUT OF HARRIS TEETER IN BRISTOW CENTER
Apr 27, 10:47 PM EDT	TORNADO	2 S Nokesville, VA	CORRECTED START LOCATION OF TRACK AFTER DAMAGE SURVEY TODAY. TORNADO WAS RATED EF-1. ADDITIONAL DAMAGE INCLUDES NUMEROUS SNAPPED AND UPROOTED TREES...SIDING AND SHINGLE REMOVAL...DETACHED GARAGE DOOR FAILURE AND DESTRUCTION OF SEVERAL HORSE RUN-INS. STRUCTURAL
Apr 27, 10:57 PM EDT	TORNADO	3 Ne Nokesville, VA	STRUCTURAL DAMAGE TO RETAIL SHOPPING CENTER.

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

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched 2 storm reports to this tornado warning; the first came 19 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

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

Issued	Product	Office	Lasted
Apr 27, 6:15 PM EDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 2.5 hours before the alert went out and 24 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1143 J/kg
Mixed-layer CIN: -34 J/kg
Mixed-layer LCL: 834 m above ground
0-6 km bulk shear: 47 kt
0-1 km storm-relative helicity: 283 m²/s²
0-3 km storm-relative helicity: 353 m²/s²
Significant tornado parameter: 1.8
Supercell composite: 14.0

Open this sounding in Storm Lab

The text

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

283 
WFUS51 KLWX 280228
TORLWX
VAC061-153-683-685-280315-
/O.NEW.KLWX.TO.W.0035.110428T0228Z-110428T0315Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1028 PM EDT WED APR 27 2011

THE NATIONAL WEATHER SERVICE IN STERLING VIRGINIA HAS ISSUED A

* TORNADO WARNING FOR...
  CITY OF MANASSAS IN NORTHERN VIRGINIA...
  CITY OF MANASSAS PARK IN NORTHERN VIRGINIA...
  FAUQUIER COUNTY IN NORTHERN VIRGINIA...
  PRINCE WILLIAM COUNTY IN NORTHERN VIRGINIA...

* UNTIL 1115 PM EDT

* AT 1025 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 20 MILES
  SOUTHWEST OF BULL RUN...OR 11 MILES SOUTH OF WARRENTON...MOVING
  NORTHEAST AT 40 MPH.

* LOCATIONS IMPACTED INCLUDE...
  BULL RUN...

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.

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

&&

LAT...LON 3883 7753 3883 7750 3879 7749 3880 7745
      3878 7742 3875 7742 3875 7739 3871 7738
      3872 7736 3872 7733 3853 7772 3861 7778
      3886 7757
TIME...MOT...LOC 0228Z 226DEG 36KT 3858 7772

$$
MANNING

3 follow-up statements

505 
WWUS51 KLWX 280249
SVSLWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1049 PM EDT WED APR 27 2011

VAC061-280259-
/O.CAN.KLWX.TO.W.0035.000000T0000Z-110428T0315Z/
FAUQUIER VA-
1049 PM EDT WED APR 27 2011

...THE TORNADO WARNING IS CANCELLED FOR FAUQUIER COUNTY...

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

LAT...LON 3883 7753 3883 7750 3879 7749 3880 7745
      3878 7742 3875 7742 3875 7739 3871 7738
      3872 7735 3864 7758 3869 7762 3886 7757
TIME...MOT...LOC 0249Z 226DEG 25KT 3868 7759

$$

VAC153-683-685-280315-
/O.CON.KLWX.TO.W.0035.000000T0000Z-110428T0315Z/
CITY OF MANASSAS VA-CITY OF MANASSAS PARK VA-PRINCE WILLIAM VA-
1049 PM EDT WED APR 27 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1115 PM EDT FOR THE CITY
OF MANASSAS...THE CITY OF MANASSAS PARK...AND PRINCE WILLIAM
COUNTY...

AT 1048 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS
TORNADO WAS LOCATED 9 MILES SOUTHWEST OF BULL RUN...OR 11 MILES EAST
OF WARRENTON...MOVING NORTHEAST AT 30 MPH.

LOCATIONS IMPACTED INCLUDE...
  BULL RUN...
  MANASSAS PARK...
  SUDLEY...

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.

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

&&

LAT...LON 3883 7753 3883 7750 3879 7749 3880 7745
      3878 7742 3875 7742 3875 7739 3871 7738
      3872 7735 3864 7758 3869 7762 3886 7757
TIME...MOT...LOC 0249Z 226DEG 25KT 3868 7759

$$
MANNING

906 
WWUS51 KLWX 280257
SVSLWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1057 PM EDT WED APR 27 2011

VAC153-683-685-280315-
/O.CON.KLWX.TO.W.0035.000000T0000Z-110428T0315Z/
CITY OF MANASSAS VA-CITY OF MANASSAS PARK VA-PRINCE WILLIAM VA-
1057 PM EDT WED APR 27 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1115 PM EDT FOR THE CITY
OF MANASSAS...THE CITY OF MANASSAS PARK...AND PRINCE WILLIAM
COUNTY...

AT 1052 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS
TORNADO WAS LOCATED 7 MILES SOUTHWEST OF BULL RUN...OR 12 MILES EAST
OF WARRENTON...MOVING NORTHEAST AT 30 MPH.

LOCATIONS IMPACTED INCLUDE...
  BULL RUN...
  MANASSAS AIRPORT... 
  MANASSAS PARK...
  MANASSAS...
  SUDLEY...

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.

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

&&

LAT...LON 3879 7749 3880 7745 3878 7742 3875 7742
      3875 7740 3867 7756 3869 7760 3878 7757
      3883 7753 3883 7750
TIME...MOT...LOC 0257Z 226DEG 25KT 3872 7754

$$
MANNING

236 
WWUS51 KLWX 280308
SVSLWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1108 PM EDT WED APR 27 2011

VAC153-683-685-280318-
/O.EXP.KLWX.TO.W.0035.000000T0000Z-110428T0315Z/
CITY OF MANASSAS VA-CITY OF MANASSAS PARK VA-PRINCE WILLIAM VA-
1108 PM EDT WED APR 27 2011

...THE TORNADO WARNING WILL EXPIRE AT 1115 PM EDT FOR THE CITY OF
MANASSAS...THE CITY OF MANASSAS PARK...AND PRINCE WILLIAM COUNTY...

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

A TORNADO WATCH REMAINS IN EFFECT UNTIL 2 AM. 

LAT...LON 3879 7749 3880 7745 3878 7742 3875 7742
      3875 7740 3867 7756 3869 7760 3878 7757
      3883 7753 3883 7750
TIME...MOT...LOC 0308Z 226DEG 25KT 3877 7747

$$
MANNING

What forecasters said that day

The local office's own words before this tornado 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 tornado warning went out at Apr 27, 9:48 PM EDT, 40 minutes earlier.

Area forecast discussion, Apr 27, 9:48 PM EDT, 40 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
948 PM EDT WED APR 27 2011

.SYNOPSIS...
A COLD FRONT WILL CROSS THE MID-ATLANTIC REGION THURSDAY. HIGH
PRESSURE BUILDING IN AT THE END OF THE WEEK WILL BRING DRIER AND
COOLER CONDITIONS THROUGH THE WEEKEND. AFTER A MODEST TEMPERATURE
RECOVERY LATE IN THE WEEKEND...A SECOND COLD FRONT MAY IMPACT THE
AREA MONDAY OR TUESDAY.

&&

.NEAR TERM /THROUGH THURSDAY/...
MOIST UNSTABLE AIR MASS REMAINS IN PLACE ACROSS THE CWA. THIS
COMBINED WITH DECENT SHEAR HAS SUPPORTED ORGANIZED SUPERCELLULAR
CONVECTION DURING THE LATE AFTERNOON AND EVENING. TORNADO WATCH
CURRENTLY GOES UNTIL 06Z. SEVERE THREAT MAY DIMINISH BEFORE
THEN...BUT CONSIDERING THE 00Z KIAD SOUNDING AND LATEST RADAR
TRENDS THE THREAT FOR SEVERE MAY CONTINUE UNTIL 03Z OR 04Z...MAINLY
IN A CORRIDOR FROM THE NORTH CENTRAL VIRIGNIA PIEDMONT UP THROUGH
DC AND CENTRAL MARYLAND WITH THE INTIAL CLUSTERS OF THUNDERSTORMS.

THEN...THERE IS THE ACTIVITY TO THE WEST TO CONSIDER. THIS WILL
LEAD TO ADDITIONAL SHOWERS AND THUNDERSTORMS AFTER MIDNIGHT
BEGINNING WEST OF THE BLUE RIDGE. A SEVERE THREAT WILL LIKELY BE
RENEWED LATE TONIGHT AS POTENT SHORTWAVE/COLD FRONT APPROACH FROM THE
WEST. HRRR/WRF ARW SUGGEST AN ORGANIZED LINE OF CONVECTION
OCCURRING WITH DAMAGING WINDS THE MAIN THREAT BUT PERHAPS AN
ISOLATED TORNADO THREAT AS WELL.

FRONT WILL MOVE FROM WEST TO EAST ACROSS THE CWA ON THURSDAY.
SEVERE THREAT WILL DIMINISH BEHIND THE FRONT IN THE EARLY
AFTERNOON.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY/...
COLD FRONT WILL MOVE OFF THE COAST WHILE THE UPPER TROUGH WILL
PROGRESS THRU THE AREA...WHICH WILL ENHANCE CLOUD COVER OVER THE CWA
THRU FRI...BUT IT SHOULD STAY DRY ACROSS MOST OF THE AREA. THE
EXCEPTION WILL BE THE WRN SLOPES OF THE ALLEGHENY FRONT AS
CYCLONIC/UPSLOPE FLOW AROUND THE TROUGH WILL PRODUCE SCT SHOWERS.
FRI WILL FEEL MORE LIKE SPRING...WITH HIGHS IN THE 60S ACROSS THE
HIGHLANDS AND NEAR 70F EAST OF THE BLUE RIDGE...AND DEWPOINTS IN THE
30S AND 40S. A TIGHT PRESSURE GRADIENT BETWEEN THE EXITING LOW AND
HIPRES BUILDING IN FROM THE SOUTHEAST WILL PRODUCE BREEZY CONDITIONS
WITH AFTN GUSTS 25 TO 35 MPH.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
HIPRES DOMINATES THE REGIONAL WX PATTERN THRU MUCH OF THE WEEKEND
BEFORE IT MOVES OFF THE COAST SUN. A NRN STREAM SHORTWAVE TROUGH
WILL TRACK ACROSS THE GREAT LAKES REGION WHILE THE ASSOCIATED COLD
FRONT PUSHES THRU THE MID-ATLANTIC REGION MON/TUE. THERE ARE STILL
TIMING DIFFERENCES AMONG OPERATIONAL MODELS. THIS SYSTEM WILL BRING
CHANCES FOR SHOWERS AND POSSIBLY STORMS DEPENDING ON THE EXACT
TIMING OF FROPA.

&&

.AVIATION /01Z THURSDAY THROUGH MONDAY/...
UNTIL ABOUT 03Z OR 04Z...THERE REMAINS A RISK OF A THUNDERSTORM
AFFECTING THE HUBS. THERE SHOULD BE A LULL THEREAFTER BEFORE MORE
SHOWERS/THUNDERSTORMS MOVE IN LATER TONIGHT INTO THURSDAY MORNING.
HAVE INCLUDED PREVAILING SHRA WITH VCTS/CB IN A 3 HOUR OR SO PERIOD
TO INDICATE THE MOST LIKELY TIME WITH THE GREATEST CONFIDENCE FOR
THIS OCCURRENCE. COLD FRONT MOVES FROM WEST TO EAST ON THURSDAY
ENDING THE RISK FOR THUNDERSTORMS AND USHERING IN A WIND SHIFT TO
THE WEST/NORTHWEST.

VFR CONDITIONS THU NGT THRU THE WEEKEND AS HIPRES BUILDS INTO THE
AREA. A TIGHT PRESSURE GRADIENT BETWEEN THE BUILDING HIGH AND
EXITING LOPRES TO OUR NORTH WILL CREATE BREEZY CONDITIONS FRI WITH
GUSTS TO 30 KT POSSSIBLE.

&&

.MARINE...
SCA REMAINS IN EFFECT TONIGHT FOR GRADIENT WIND IN SOUTHERLY FLOW.
OBVIOUSLY ANY EVENING THUNDERSTORMS CAN BRING STRONGER WIND GUSTS
WHICH WOULD BE HANDLED WITH SMW/S. GRADIENT TIGHTENS FURTHER LATER
TONIGHT AND THURSDAY MORNING AHEAD OF A COLD FRONT. GALES ARE UP
FOR THE LOWER MD BAY/POTOMAC AREA WITH SOLID SCA ELSEWHERE.
ORGANIZED THUNDERSTORMS MAY PRODUCE STRONG GUSTY WINDS THURSDAY
MORNING-EARLY AFTERNOON AS WELL.

SCA CONTINUES INTO THU EVE FOR THE LOWER HALF OF THE MD CHSPK BAY
AND THE LWR TIDAL POTOMAC. AFTER A BRIEF LULL IN THE WINDSWINDS WILL
RELAX THIS WEEKEND AS HIPRES SETTLES OVER THE AREA. SLY WINDS WILL
INCREASE TO NEAR SCA LVLS AHEAD OF THE NEXT COLD FRONT LATE SUN INTO
MON.

&&

.TIDES/COASTAL FLOODING...
POSITIVE TIDAL ANOMALIES WILL CONTINUE THROUGH AT LEAST THE NEXT
HIGH TIDE CYCLE. ANOMALIES WERE RUNNING 1/2 FT TO 1 FT ABOVE
NORMAL THIS EVENING AND MAY INCREASE A LITTLE THROUGH THE NEXT
CYCLE. SENSITIVE LOCATIONS SUCH AS ANNAPOLIS MAY COME CLOSE TO
MINOR TIDAL FLOODING THRESHOLDS AND WILL NEED TO BE WATCHED
CLOSELY. LATEST FORECAST PUTS ANNAPOLIS AT 2.2 OR 2.3 FT MLLW
WHICH IS JUST BELOW THE THRESHOLD OF 2.4 FT.

&&

.CLIMATE...
RECORD HIGH MIN TEMPS WILL LIKELY BE BROKEN AGAIN...THIS TIME AT DCA
AND IAD WHILE BWI ALREADY DROPPED 1F BELOW THE CURRENT RECORD HIGH
MIN TEMP. A LIST OF THE MIN TEMPS THIS MRNG AND 4/27 RECORD HIGH MIN
TEMPS FOR THE THREE MAJOR AIRPORTS ARE LISTED BELOW...

MIN TEMPS SO FAR TODAY /AS OF 12 PM EDT/
DCA   66
BWI   67
IAD   68

RECORD HI MIN TEMPS FOR 4/27
   MIN TEMP   YR

DCA   65     1908/1990/1994
BWI   68     1915
IAD   63     2009

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR MDZ003-501-502.
VA...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR VAZ025>028-503-
     504.
WV...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR WVZ050>052-055-
     501>506.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THURSDAY FOR ANZ530>532-
     535-536-538>540-542.
     SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT THURSDAY NIGHT FOR
     ANZ533-541.
     SMALL CRAFT ADVISORY UNTIL 6 AM EDT THURSDAY FOR ANZ534-537-
     543.
     SMALL CRAFT ADVISORY FROM 6 PM THURSDAY TO MIDNIGHT EDT
     THURSDAY NIGHT FOR ANZ534-537-543.
     GALE WARNING FROM 6 AM TO 6 PM EDT THURSDAY FOR ANZ534-537-543.

&&

PELOQUIN/KRAMAR/JRK

Hazardous weather outlook, Apr 27, 6:35 PM EDT, 3 hours 53 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
635 PM EDT WED APR 27 2011

ANZ530>543-DCZ001-MDZ006-007-011-013-014-016>018-VAZ052>057-
281000-
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-
PATAPSCO RIVER INCLUDING BALTIMORE HARBOR-
CHESTER RIVER TO QUEENSTOWN MD-EASTERN BAY-
CHOPTANK RIVER TO CAMBRIDGE MD AND THE LITTLE CHOPTANK RIVER-
PATUXENT RIVER TO BROOMES ISLAND MD-
TANGIER SOUND AND THE INLAND WATERS SURROUNDING BLOODSWORTH
ISLAND-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-
635 PM EDT WED APR 27 2011

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 TORNADO WATCH IS IN EFFECT UNTIL 2 AM LATE TONIGHT FOR THE
OUTLOOK AREA. THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS
EVENING. ANY STORMS THIS EVENING WILL HAVE THE POTENTIAL TO
PRODUCE DAMAGING WIND GUSTS...LARGE HAIL AND A FEW TORNADOES.

THERE IS ALSO A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR ALL OF
THE OUTLOOK AREA TOWARD DAYBREAK. A COLD FRONT WILL CROSS THE
AREA LATE TONIGHT. ANY THUNDERSTORMS ALONG AND AHEAD OF THE COLD
FRONT WILL BE CAPABLE OF PRODUCING DAMAGING WINDS AND LARGE HAIL.

A SMALL CRAFT ADVISORY IS IN EFFECT THROUGH TONIGHT FOR THE
MARYLAND CHESAPEAKE BAY AND THE TIDAL POTOMAC RIVER.

TIDAL DEPARTURES WILL INCREASE TODAY AS SOUTHERLY FLOW STRENGTHENS
TODAY. WATER LEVELS MAY APPROACH THRESHOLDS FOR MINOR COASTAL
FLOODING LATE TONIGHT FOR LOW-LYING AREAS ALONG THE TIDAL POTOMAC
RIVER AND THE WESTERN SHORE OF THE MARYLAND CHESAPEAKE BAY.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

MINOR COASTAL FLOODING IS POSSIBLE THURSDAY ALONG THE TIDAL
POTOMAC RIVER AND THE WESTERN SHORE OF THE MARYLAND CHESAPEAKE
BAY.

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ON THURSDAY ACROSS
THE OUTLOOK AREA. THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG AND
AHEAD OF A COLD FRONT THAT WILL CROSS THE REGION. SOME STORMS MAY
BE SEVERE AND WILL BE CAPABLE OF PRODUCING DAMAGING WIND GUSTS
AND LARGE HAIL. STORMS ALSO MAY PRODUCE VERY HEAVY RAINFALL THAT
COULD LEAD TO LOCALIZED FLASH FLOODING.

A GALE WARNING IS IN EFFECT THURSDAY FOR THE MARYLAND CHESAPEAKE
BAY FROM DRUM POINT TO SMITH POINT...AND FOR THE TIDAL POTOMAC
RIVER FROM COBB ISLAND TO SMITH POINT. A SMALL CRAFT ADVISORY IS
IN EFFECT FOR THE REMAINDER OF THE MARYLAND CHESAPEAKE BAY AND
TIDAL POTOMAC RIVER.

THE SMALL CRAFT ADVISORY CONTINUES THURSDAY EVENING FOR THE LOWER
TIDAL POTOMAC RIVER AND THE MARYLAND CHESAPEAKE BAY SOUTH OF NORTH
BEACH.

A SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED FOR THE WATERS FRIDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL BE NEEDED THIS AFTERNOON AND LIKELY WILL
BE NEEDED LATE TONIGHT AND THURSDAY.

MDZ003>005-009-010-501-502-VAZ025>031-036>040-042-050-051-501>504-
WVZ050>053-055-501>506-281000-
WASHINGTON-FREDERICK MD-CARROLL-MONTGOMERY-HOWARD-
EXTREME WESTERN ALLEGANY-CENTRAL AND EASTERN ALLEGANY-AUGUSTA-
ROCKINGHAM-SHENANDOAH-FREDERICK VA-PAGE-WARREN-CLARKE-NELSON-
ALBEMARLE-GREENE-MADISON-RAPPAHANNOCK-LOUDOUN-ORANGE-CULPEPER-
NORTHERN FAUQUIER-SOUTHERN FAUQUIER-WESTERN HIGHLAND-
EASTERN HIGHLAND-HAMPSHIRE-MORGAN-BERKELEY-JEFFERSON-HARDY-
WESTERN GRANT-EASTERN GRANT-WESTERN MINERAL-EASTERN MINERAL-
WESTERN PENDLETON-EASTERN PENDLETON-
635 PM EDT WED APR 27 2011

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 TORNADO WATCH IS IN EFFECT FOR THE OUTLOOK AREA UNTIL 2 AM LATE
TONIGHT. THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THROUGH TONIGHT
FOR THE ENTIRE OUTLOOK AREA. SOME STORMS WILL BE CAPABLE OF
PRODUCING DAMAGING WIND GUSTS...LARGE HAIL AND TORNADOES. STORMS
WILL DEVELOP ALONG AND AHEAD OF A COLD FRONT LATE TONIGHT AND ALSO
COULD BE SEVERE. SOME STORMS ALSO COULD PRODUCE HEAVY RAINFALL
THAT COULD LEAD TO FLASH FLOODING.

A FLASH FLOOD WATCH IS IN EFFECT LATE TONIGHT FOR THE POTOMAC
HIGHLANDS...NORTHERN AND CENTRAL SHENANDOAH VALLEY...NORTH-CENTRAL
MARYLAND AND THE EASTERN WEST VIRGINIA PANHANDLE. PLEASE REFER TO
THE LATEST HAZARD MESSAGE /FFALWX/ FOR DETAILS.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THURSDAY FOR
COUNTIES ALONG AND EAST OF THE BLUE RIDGE MOUNTAINS. SOME STORMS
WILL BE CAPABLE OF PRODUCING DAMAGING WIND GUSTS AND LARGE HAIL.
SOME STORMS COULD PRODUCE HEAVY RAINFALL THAT COULD LEAD TO FLASH
FLOODING.

A WIND ADVISORY MAY BE NEEDED FOR THE RIDGE TOPS OF THE POTOMAC
AND ALLEGHENY HIGHLANDS THURSDAY FOR STRONG WINDS BEHIND THE COLD
FRONT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL BE NEEDED THIS AFTERNOON...AND LIKELY WILL
BE NEEDED LATE TONIGHT THROUGH THURSDAY.

In the hours before

Local storm report, Apr 27, 7:44 PM EDT, 2 hours 44 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
744 PM EDT WED APR 27 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0725 PM     FUNNEL CLOUD     1 WNW BRYANS ROAD       38.63N  77.09W
04/27/2011                   CHARLES            MD   BROADCAST MEDIA

            FUNNEL CLOUD REPORTED BETWEEN INDIAN HEAD AND ACCOKEEK

&&

EVENT NUMBER LWX1100527

KLW

Special weather statement, Apr 27, 7:55 PM EDT, 2 hours 33 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
755 PM EDT WED APR 27 2011

VAZ050-051-055>057-280130-
ORANGE-CULPEPER-STAFFORD-SPOTSYLVANIA-KING GEORGE-
INCLUDING THE CITIES OF...CULPEPER...FREDERICKSBURG
755 PM EDT WED APR 27 2011

...STRONG STORMS APPROACHING NORTH CENTRAL VIRGINIA...

TORNADOS HAVE BEEN REPORTED IN CENTRAL VIRGINIA WITH STORMS THAT
ARE MOVING NORTHEAST TOWARDS ORANGE... CULPEPER... STAFFORD...
SPOTSYLVANIA... AND KING GEORGE COUNTIES. PEOPLE IN THESE COUNTIES
INCLUDING THE FREDERICKSBURG AREA SHOULD BE READY TO TAKE COVER
THIS EVENING IF TORNADO WARNINGS ARE ISSUED. KNOW WHERE YOU WILL
SHELTER. THE BEST PLACES ARE IN STURDY HOMES AND SHELTERS IN THE
LOWEST LEVEL AWAY FROM WINDOWS.

STRONG

Special weather statement, Apr 27, 8:02 PM EDT, 2 hours 26 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
802 PM EDT WED APR 27 2011

MDZ009-VAZ031-042-052-501-502-WVZ053-280030-
MONTGOMERY MD-NORTHERN FAUQUIER VA-CLARKE VA-LOUDOUN VA-JEFFERSON WV-
PRINCE WILLIAM/MANASSAS/MANASSAS PARK VA-SOUTHERN FAUQUIER VA-
802 PM EDT WED APR 27 2011

...STRONG THUNDERSTORM TO AFFECT MONTGOMERY...NORTHERN FAUQUIER...
CLARKE...LOUDOUN...JEFFERSON...PRINCE WILLIAM/MANASSAS/MANASSAS PARK
AND SOUTHERN FAUQUIER COUNTIES...

AT 802 PM EDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM 3 MILES
WEST OF BETHEL...MOVING NORTHEAST AT 60 MPH.

LOCATIONS IMPACTED INCLUDE MARSHALL...THE PLAINS...HALFWAY...
MIDDLEBURG...HUGHESVILLE...OATLANDS AND HAMILTON.

PENNY-SIZE TO NICKEL-SIZE HAIL CAN BE EXPECTED WITH THIS STORM.

&&

LAT...LON 3918 7789 3912 7741 3866 7780 3874 7801
TIME...MOT...LOC 0002Z 208DEG 50KT 3879 7785

KRAMAR/SBK

Special weather statement, Apr 27, 8:51 PM EDT, 1 hour 37 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
851 PM EDT WED APR 27 2011

VAZ037>039-280115-
GREENE VA-MADISON VA-ALBEMARLE VA-
851 PM EDT WED APR 27 2011

...STRONG THUNDERSTORM TO AFFECT GREENE...MADISON AND ALBEMARLE
COUNTIES...

AT 851 PM EDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM 2 MILES
SOUTHEAST OF FREE UNION...MOVING NORTHEAST AT 55 MPH.

LOCATIONS IMPACTED INCLUDE STANARDSVILLE AND MADISON.

STORM INTENSITY IS INCREASING...AND SEVERE WEATHER MAY DEVELOP
RAPIDLY. REMAIN ALERT...AND BE PREPARED TO TAKE ACTION IF WARNINGS
ARE ISSUED.

WIND GUSTS IN EXCESS OF 50 MPH AND SMALL HAIL CAN BE EXPECTED WITH
THIS STORM. WINDS THIS STRONG CAN BRING DOWN LARGE TREE BRANCHES.
TAKE SHELTER UNTIL THE STORM HAS PASSED.

&&

LAT...LON 3859 7831 3846 7817 3807 7846 3816 7867
TIME...MOT...LOC 0051Z 211DEG 48KT 3819 7850

MANNING

Special weather statement, Apr 27, 8:56 PM EDT, 1 hour 32 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
856 PM EDT WED APR 27 2011

MDZ004-005-280130-
CARROLL MD-FREDERICK MD-
856 PM EDT WED APR 27 2011

...STRONG THUNDERSTORM TO AFFECT CARROLL AND FREDERICK COUNTIES...

AT 856 PM EDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM OVER
WALKERSVILLE...MOVING NORTHEAST AT 60 MPH.

LOCATIONS IMPACTED INCLUDE THURMONT...EMMITSBURG AND TANEYTOWN.

PENNY-SIZE TO NICKEL-SIZE HAIL CAN BE EXPECTED WITH THIS STORM.

&&

LAT...LON 3937 7731 3942 7750 3973 7743 3972 7696
TIME...MOT...LOC 0056Z 204DEG 53KT 3952 7737

KRAMAR/SBK

Local storm report, Apr 27, 10:09 PM EDT, 19 minutes before

PRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1009 PM EDT WED APR 27 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0722 PM     TORNADO          1 S MORNINGSIDE         38.82N  76.89W
04/27/2011                   PRINCE GEORGES     MD   TRAINED SPOTTER

            LARGE BRANCHES AND SHINGLES ON ALLENTOWN ROAD. A BIG
            ROAD SIGN BLOWN DOWN NEAR ANDREWS AIRFORCE BASE.

&&

CORRECTED EVENT TIME...EVENT

EVENT NUMBER LWX1100525

LEE

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 27, 8:02 PM EDT	Special Weather Statement	LWX	Fauquier, Loudoun	28 min
Apr 27, 8:12 PM EDT	Severe Thunderstorm Warning	LWX	Orange, Spotsylvania	28 min
Apr 27, 8:19 PM EDT	Severe Thunderstorm Warning	LWX	Fauquier, Loudoun, Prince William	36 min
Apr 27, 8:20 PM EDT	Tornado Warning	LWX	Albemarle, City of Charlottesville	25 min
Apr 27, 8:28 PM EDT	Severe Thunderstorm Warning	LWX	Clarke, Fauquier, Loudoun, Warren	19 min
Apr 27, 8:30 PM EDT	Tornado Warning	LWX	Orange, Spotsylvania	30 min
Apr 27, 8:51 PM EDT	Special Weather Statement	LWX	Greene, Madison	24 min
Apr 27, 9:24 PM EDT	Tornado Warning	LWX	Culpeper, Fauquier, Orange, Spotsylvania, Stafford	18 min
Apr 27, 9:40 PM EDT	Tornado Warning	LWX	Culpeper, Madison, Orange	35 min
Apr 27, 10:00 PM EDT	Tornado Warning	LWX	Culpeper, Fauquier	30 min
Apr 27, 10:39 PM EDT	Special Weather Statement	LWX	Highland	111 min
Apr 28, 12:04 AM EDT	Severe Thunderstorm Warning	LWX	Highland	71 min
Apr 28, 12:05 AM EDT	Flash Flood Warning	LWX	Highland	5 hr
Apr 28, 1:09 AM EDT	Severe Thunderstorm Warning	LWX	Augusta, Highland, Rockingham	66 min
Apr 28, 1:29 AM EDT	Severe Thunderstorm Warning	LWX	Frederick	35 min
Apr 28, 1:33 AM EDT	Flash Flood Warning	LWX	Rockingham, Shenandoah	4 hr
Apr 28, 2:07 AM EDT	Tornado Warning	LWX	Augusta, City of Staunton	42 min
Apr 28, 2:10 AM EDT	Severe Thunderstorm Warning	LWX	Frederick, Page, Rockingham, Shenandoah, Warren	65 min
Apr 28, 2:24 AM EDT	Tornado Warning	LWX	Shenandoah	25 min
Apr 28, 2:53 AM EDT	Tornado Warning	LWX	Page, Rockingham, Shenandoah, City of Harrisonburg	36 min
Apr 28, 2:59 AM EDT	Severe Thunderstorm Warning	LWX	Clarke, Frederick, Loudoun, Warren, City of Winchester	62 min
Apr 28, 3:04 AM EDT	Flash Flood Warning	LWX	Clarke, Frederick, Page, Rockingham, Shenandoah, Warren and 1 more	7 hr
Apr 28, 3:09 AM EDT	Special Weather Statement	LWX	Augusta	36 min
Apr 28, 3:19 AM EDT	Tornado Warning	LWX	Augusta, City of Staunton	41 min
Apr 28, 3:23 AM EDT	Tornado Warning	LWX	Clarke, Frederick, Page, Shenandoah, Warren	39 min
Apr 28, 3:50 AM EDT	Tornado Warning	LWX	Page, Rockingham, Shenandoah, City of Harrisonburg	40 min
Apr 28, 3:54 AM EDT	Tornado Warning	LWX	Clarke, Frederick, City of Winchester	34 min
Apr 28, 4:26 AM EDT	Tornado Warning	LWX	Fauquier, Page, Rappahannock, Warren	23 min
Apr 28, 4:32 AM EDT	Special Weather Statement	LWX	Albemarle, Greene, Nelson, City of Charlottesville, City of Waynesboro	28 min
Apr 28, 4:44 AM EDT	Severe Thunderstorm Warning	LWX	Albemarle, Culpeper, Greene, Madison, Orange, Rappahannock and 1 more	46 min
Apr 28, 5:09 AM EDT	Special Weather Statement	LWX	Loudoun	51 min
Apr 28, 5:35 AM EDT	Tornado Warning	LWX	Loudoun	26 min
Apr 28, 5:50 AM EDT	Tornado Warning	LWX	Culpeper, Fauquier, Prince William, Rappahannock	40 min
Apr 28, 6:05 AM EDT	Special Marine Warning	LWX		55 min
Apr 28, 6:37 AM EDT	Tornado Warning	LWX	Loudoun	38 min
Apr 28, 7:27 AM EDT	Flash Flood Warning	LWX	Loudoun	5 hr
Apr 28, 8:01 AM EDT	Flash Flood Warning	LWX	Clarke, Loudoun	119 min
Apr 28, 8:45 AM EDT	Areal Flood Warning	LWX	Albemarle, Clarke, Culpeper, Fauquier, Greene, Loudoun and 3 more	6 hr
Apr 28, 9:39 AM EDT	Severe Thunderstorm Warning	LWX	Fairfax, Loudoun	36 min
Apr 28, 9:45 AM EDT	Flash Flood Warning	LWX	Fairfax, Fauquier, Loudoun, Prince William	101 min
Apr 28, 9:58 AM EDT	Areal Flood Warning	LWX	Loudoun	3 hr
Apr 28, 10:03 AM EDT	Severe Thunderstorm Warning	LWX	King George, Spotsylvania, Stafford, City of Fredericksburg	42 min
Apr 28, 10:06 AM EDT	Special Marine Warning	LWX		84 min
Apr 28, 10:16 AM EDT	Special Marine Warning	LWX		59 min
Apr 28, 10:38 AM EDT	Severe Thunderstorm Warning	LWX	King George	52 min
Apr 28, 10:59 AM EDT	Special Marine Warning	LWX		81 min
Apr 28, 11:38 AM EDT	Coastal Flood Advisory	LWX	Arlington, Fairfax, King George, Stafford, City of Alexandria, City of Fairfax and 1 more	7 hr
Apr 28, 3:34 PM EDT	Small Craft Advisory	LWX		37 hr
Apr 28, 4:07 PM EDT	Special Marine Warning	LWX		53 min
Apr 28, 4:15 PM EDT	Special Marine Warning	LWX		60 min
Apr 28, 4:51 PM EDT	Special Marine Warning	LWX		36 min

Nearby

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