Alert archive / Maryland / Tornado Warnings in 2011

Tornado Warning 9, NWS Baltimore/Washington

April 5, 2011Calvert County, Saint Mary's County, Maryland

NWS Baltimore/Washington issued this tornado warning at Apr 5, 2011, 5:22 AM EDT for Calvert County, Saint Mary's County, Maryland. It was in force for 23 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
Apr 5, 2011, 5:22 AM EDT (09:22 UTC)
Expired
Apr 5, 2011, 5:45 AM EDT
In force
23 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon

Counties Calvert County, MD, Saint Mary's County, MD

The radar

The Dover AFB radar (KDOX), 112 km from the middle of the area, began a volume at 09:25 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
Apr 5, 5:24 AM EDTTSTM WND DMGValley Lee, MDTREE FELL ON MOBILE HOME

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
Apr 5, 2:18 AM EDTTornado WatchSPC8 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 00:00Z, 9.4 hours before the alert went out and 95 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, Wallops Is Stn, VA at 00:00Z on 2011-04-05Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Wallops Is Stn, VA at 00:00Z on 2011-04-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 229 square meters per square second.19395878Sfc1 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
1729 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
229 m²/s²
0-3 km storm-relative helicity
317 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.

933 
WFUS51 KLWX 050922
TORLWX
MDC009-037-051000-
/O.NEW.KLWX.TO.W.0009.110405T0922Z-110405T1000Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
522 AM EDT TUE APR 5 2011

THE NATIONAL WEATHER SERVICE IN STERLING VIRGINIA HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHEASTERN CALVERT COUNTY IN SOUTHERN MARYLAND...
  SOUTHEASTERN ST. MARYS COUNTY IN SOUTHERN MARYLAND...

* UNTIL 600 AM EDT

* AT 521 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 10 MILES
  SOUTHWEST OF SAINT GEORGE ISLAND...OR NEAR CALLAO...MOVING
  NORTHEAST AT 70 MPH.

* LOCATIONS IMPACTED INCLUDE...
  SAINT GEORGE ISLAND...
  SAINT INIGOES CREEK...
  SAINT MARYS RIVER...
  SAINT MARYS CITY...
  LEXINGTON PARK...

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 3810 7640 3810 7642 3812 7645 3810 7648
      3813 7650 3813 7653 3818 7655 3821 7661
      3841 7640 3839 7637 3832 7640 3830 7636
      3825 7638 3814 7631 3803 7631
TIME...MOT...LOC 0922Z 235DEG 60KT 3801 7660

$$

LEE/GMS
3 follow-up statements
258 
WWUS51 KLWX 050931
SVSLWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
531 AM EDT TUE APR 5 2011

MDC009-037-051000-
/O.CON.KLWX.TO.W.0009.000000T0000Z-110405T1000Z/
CALVERT MD-ST. MARYS MD-
531 AM EDT TUE APR 5 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 600 AM EDT FOR
SOUTHEASTERN ST. MARYS AND EXTREME SOUTHEASTERN CALVERT COUNTIES...

AT 526 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING
TORNADOES.  THESE TORNADOES WERE LOCATED ALONG A LINE EXTENDING FROM
PINEY POINT TO LEWISETTA...MOVING NORTHEAST AT 70 MPH.

LOCATIONS IMPACTED INCLUDE...
  CHESAPEAKE RANCH ESTATES...
  COVE POINT...

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 3810 7640 3810 7642 3812 7645 3810 7648
      3813 7650 3813 7653 3818 7655 3821 7661
      3841 7640 3839 7637 3832 7640 3830 7636
      3825 7638 3814 7631 3803 7631
TIME...MOT...LOC 0931Z 230DEG 63KT 3817 7644 3807 7642

$$

LEE
501 
WWUS51 KLWX 050937
SVSLWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
537 AM EDT TUE APR 5 2011

MDC009-037-051000-
/O.CON.KLWX.TO.W.0009.000000T0000Z-110405T1000Z/
CALVERT MD-ST. MARYS MD-
537 AM EDT TUE APR 5 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 600 AM EDT FOR
SOUTHEASTERN ST. MARYS AND EXTREME SOUTHEASTERN CALVERT COUNTIES...

AT 536 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS 
TORNADO WAS LOCATED 5 MILES SOUTH OF SAINT INIGOES CREEK NEAR 
SCOTLAND...MOVING NORTHEAST AT 65 MPH.

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 3810 7640 3810 7642 3812 7645 3810 7648
      3813 7650 3813 7653 3818 7655 3821 7661
      3841 7640 3839 7637 3832 7640 3830 7636
      3825 7638 3814 7631 3803 7631
TIME...MOT...LOC 0937Z 242DEG 56KT 3806 7634

$$

LEE/GMS
502 
WWUS51 KLWX 050945
SVSLWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
545 AM EDT TUE APR 5 2011

MDC009-037-050955-
/O.CAN.KLWX.TO.W.0009.000000T0000Z-110405T1000Z/
CALVERT MD-ST. MARYS MD-
545 AM EDT TUE APR 5 2011

...THE TORNADO WARNING IS CANCELLED FOR SOUTHEASTERN ST. MARYS AND
EXTREME SOUTHEASTERN CALVERT COUNTIES...

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

LAT...LON 3810 7640 3810 7642 3812 7645 3810 7648
      3813 7650 3813 7653 3818 7655 3821 7661
      3841 7640 3839 7637 3832 7640 3830 7636
      3825 7638 3814 7631 3803 7631
TIME...MOT...LOC 0945Z 242DEG 56KT 3812 7620

$$

LEE

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 5, 3:56 AM EDTSpecial Weather StatementLWXCarroll, Charles, Howard, Montgomery64 min
Apr 5, 4:29 AM EDTSevere Thunderstorm WarningLWXAnne Arundel, Calvert, Charles, Montgomery, Prince George's51 min
Apr 5, 4:38 AM EDTSevere Thunderstorm WarningLWXCalvert, Charles, Saint Mary's67 min
Apr 5, 4:40 AM EDTSevere Thunderstorm WarningLWXAnne Arundel, Baltimore, Carroll, Harford, Howard, Montgomery and 2 more53 min
Apr 5, 4:46 AM EDTTornado WarningLWXAnne Arundel, Calvert, Charles, Prince George's, Saint Mary's29 min
Apr 5, 4:55 AM EDTTornado WarningLWXAnne Arundel, Prince George's24 min
Apr 5, 4:57 AM EDTTornado WarningLWXCalvert, Charles, Prince George's, Saint Mary's33 min
Apr 5, 5:05 AM EDTTornado WarningLWXAnne Arundel, Calvert, Charles, Prince George's14 min
Apr 5, 8:32 AM EDTSpecial Weather StatementLWXAnne Arundel, Baltimore, Harford, Howard, Prince George's, City of Baltimore58 min
Apr 5, 9:21 AM EDTSpecial Weather StatementLWXCalvert, Charles, Saint Mary's54 min

Nearby

Tornado 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.