Alert archive / Maryland / Tornado Warnings in 2009

Tornado Warning 5, NWS Baltimore/Washington

June 20, 2009Baltimore County, Harford County, Maryland

NWS Baltimore/Washington issued this tornado warning at Jun 20, 2009, 3:46 PM EDT for Baltimore County, Harford County, Maryland. It was in force for 29 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
Jun 20, 2009, 3:46 PM EDT (19:46 UTC)
Expired
Jun 20, 2009, 4:15 PM EDT
In force
29 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon

Counties Baltimore County, MD, Harford County, MD

The watch it was issued in

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

IssuedProductOfficeLasted
Jun 20, 3:05 PM EDTTornado WatchSPC5 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 7.8 hours before the alert went out and 101 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 2009-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1441 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 2009-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 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
1441 J/kg
Mixed-layer CIN
-83 J/kg
Mixed-layer LCL
978 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
123 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.2

Open this sounding in Storm Lab

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 Jun 20, 3:27 PM EDT, 19 minutes earlier.

Area forecast discussion, Jun 20, 3:27 PM EDT, 19 minutes before
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Hazardous weather outlook, Jun 20, 11:45 AM EDT, 4 hours 1 minute before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1145 AM EDT SAT JUN 20 2009

ANZ530>537-DCZ001-MDZ006-007-011-013-014-016>018-VAZ052>057-
211000-
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-
1145 AM EDT SAT JUN 20 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...THIS AFTERNOON AND TONIGHT

NUMEROUS THUNDERSTORMS WILL MOVE ACROSS THE OUTLOOK AREA THROUGH
THIS AFTERNOON. SOME THUNDERSTORMS MAY BE SEVERE...PRODUCING
DAMAGING WIND GUSTS AND LARGE HAIL. HEAVY RAINFALL IS ALSO
POSSIBLE...WHICH COULD PRODUCE LOCALIZED FLASH FLOODING. THE MOST
LIKELY TIME FOR SEVERE WEATHER IS THROUGH 4 PM.

A SMALL CRAFT ADVISORY IS IN EFFECT FOR THE TIDAL POTOMAC RIVER
AND MARYLAND CHESAPEAKE BAY 2 PM THIS AFTERNOON INTO TONIGHT.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

A SMALL CRAFT ADVISORY CONTINUES ACROSS THE WATERS SUNDAY AND
SUNDAY EVENING. THE SMALL CRAFT ADVISORY MAY NEED TO BE EXTENDED
INTO SUNDAY NIGHT AND MONDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED THIS AFTERNOON.

MDZ003>005-009-010-501-502-VAZ021-025>031-036>042-050-051-
WVZ050>055-501>504-211000-
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-
1145 AM EDT SAT JUN 20 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...THIS AFTERNOON AND TONIGHT

NUMEROUS THUNDERSTORMS WILL MOVE ACROSS THE OUTLOOK AREA THROUGH
THIS AFTERNOON. SOME THUNDERSTORMS MAY BE SEVERE...PRODUCING
DAMAGING WIND GUSTS AND LARGE HAIL. HEAVY RAINFALL IS ALSO
POSSIBLE...WHICH COULD PRODUCE LOCALIZED FLASH FLOODING. THE MOST
LIKELY TIME FOR SEVERE WEATHER IS THROUGH 3 PM.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED THIS AFTERNOON.

In the hours before

Special weather statement, Jun 20, 11:04 AM EDT, 4 hours 42 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1104 AM EDT SAT JUN 20 2009

DCZ001-MDZ009-VAZ042-053-054-201545-
DISTRICT OF COLUMBIA DC-MONTGOMERY MD-LOUDOUN VA-
ARLINGTON/FALLS CHURCH/ALEXANDRIA VA-FAIRFAX VA-
1104 AM EDT SAT JUN 20 2009

...STRONG THUNDERSTORMS TO AFFECT THE DISTRICT OF COLUMBIA AND THE
NORTHWEST SUBURBS...

AT 11 AM EDT...A STRONG THUNDERSTORM WAS OVER WOLF TRAP AND GREAT
FALLS...MOVING RAPIDLY EAST AT 50 MPH. AT THE SAME TIME ANOTHER
STRONG STORM WAS OVER WESTERN MONTGOMERY COUNTY MOVING EAST.

LOCATIONS THAT WILL LIKELY BE AFFECTED BY THESE STRONG STORMS
INCLUDE BETHESDA...CHEVY CHASE...AMERICAN UNIVERSITY...
GEORGETOWN... WASHINGTON... ROCKVILLE...OLNEY...AND NORTH ARLINGTON.

WIND GUSTS OF 40 MPH...SMALL HAIL...AND TORRENTIAL RAIN IS EXPECTED
WITH THESE STORMS.

STRONG
Special weather statement, Jun 20, 12:01 PM EDT, 3 hours 45 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1201 PM EDT SAT JUN 20 2009

MDZ016-017-VAZ057-201630-
KING GEORGE VA-CHARLES MD-ST. MARYS MD-
1201 PM EDT SAT JUN 20 2009

...STRONG THUNDERSTORM TO AFFECT KING GEORGE...CHARLES AND ST. MARYS
COUNTIES...

AT NOON...A STRONG THUNDERSTORM WAS NEAR BEL ALTON AND PORT TOBACCO...
MOVING EAST AT 40 MPH.

LOCATIONS THAT WILL LIKELY BE AFFECTED BY THIS STORM INCLUDE
LEONARDTOWN...
NEWBURG...
FAULKNER...
DAHLGREN...
AND CHAPTICO.

BRIEF TORRENTIAL RAIN... FREQUENT LIGHTNING...WIND GUSTS UP TO 45 MPH...
AND SMALL HAIL ARE EXPECTED WITH THIS STORM.

STRONG
Special weather statement, Jun 20, 2:35 PM EDT, 1 hour 11 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
235 PM EDT SAT JUN 20 2009

VAZ041-050-051-055-056-201915-
ORANGE VA-STAFFORD VA-CULPEPER VA-FAUQUIER VA-SPOTSYLVANIA VA-
235 PM EDT SAT JUN 20 2009

...STRONG THUNDERSTORMS TO AFFECT ORANGE...STAFFORD...CULPEPER...
FAUQUIER AND SPOTSYLVANIA COUNTIES...

AT 235 PM EDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM 3 MILES
SOUTHWEST OF GOLDVEIN...MOVING SOUTHEAST AT 20 MPH.

LOCATIONS THAT WILL LIKELY BE AFFECTED BY THIS STORM INCLUDE
MASSAPONAX.

WIND GUSTS OF 40 MPH AND SMALL HAIL CAN BE EXPECTED WITH THIS STORM.

BAJ
Special weather statement, Jun 20, 3:02 PM EDT, 44 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
302 PM EDT SAT JUN 20 2009

MDZ006-007-011-201945-
NORTHERN BALTIMORE MD-HARFORD MD-SOUTHERN BALTIMORE MD-
302 PM EDT SAT JUN 20 2009

...STRONG THUNDERSTORMS TO AFFECT NORTHERN BALTIMORE...HARFORD AND
SOUTHERN BALTIMORE COUNTIES...

AT 302 PM EDT...DOPPLER RADAR INDICATED A STRONG THUNDERSTORM 2 MILES
WEST OF COCKEYSVILLE...MOVING SOUTHEAST AT 25 MPH.

LOCATIONS THAT WILL LIKELY BE AFFECTED BY THIS STORM INCLUDE
TIMONIUM...LUTHERVILLE...EUDOWOOD...LOCH RAVEN...HAMPTON...LOCH RAVEN
VILLAGE...CARNEY...GLEN ARM...PARKVILLE AND PERRY HALL.

WIND GUSTS OF 40 TO 50 MPH AND SMALL HAIL CAN BE EXPECTED WITH THIS
STORM.

BAJ
Special weather statement, Jun 20, 3:06 PM EDT, 40 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
306 PM EDT SAT JUN 20 2009

MDZ016-017-VAZ055>057-201945-
KING GEORGE VA-STAFFORD VA-CHARLES MD-ST. MARYS MD-SPOTSYLVANIA VA-
306 PM EDT SAT JUN 20 2009

...STRONG THUNDERSTORMS TO AFFECT KING GEORGE...STAFFORD...CHARLES...
ST. MARYS AND SPOTSYLVANIA COUNTIES...

AT 306 PM EDT...DOPPLER RADAR INDICATED STRONG THUNDERSTORMS ALONG A
LINE EXTENDING FROM 2 MILES WEST OF CHAPTICO TO WHITE OAK...MOVING
SOUTHEAST AT 30 MPH.

LOCATIONS THAT WILL LIKELY BE AFFECTED BY THESE STORMS INCLUDE
LEONARDTOWN...HOLLYWOOD...LEXINGTON PARK...CALIFORNIA...PATUXENT
RIVER NAS...SAINT MARYS RIVER AND SAINT INIGOES CREEK.

WIND GUSTS OF 40 MPH AND SMALL HAIL CAN BE EXPECTED WITH THESE
STORMS.

BAJ
Special weather statement, Jun 20, 3:41 PM EDT, 5 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Jun 19, 8:59 PM EDTSmall Craft AdvisoryLWX69 hr
Jun 20, 11:27 AM EDTSpecial Marine WarningLWX63 min
Jun 20, 12:09 PM EDTSpecial Marine WarningLWX51 min
Jun 20, 12:51 PM EDTSpecial Marine WarningLWX54 min
Jun 20, 2:56 PM EDTSpecial Marine WarningLWX94 min
Jun 20, 2:59 PM EDTSpecial Marine WarningLWX91 min
Jun 20, 3:36 PM EDTSpecial Marine WarningLWX54 min
Jun 20, 4:11 PM EDTSpecial Marine WarningLWX49 min
Jun 20, 4:40 PM EDTSpecial Marine WarningLWX20 min
Jun 20, 4:43 PM EDTSpecial Marine WarningLWX48 min
Jun 20, 5:04 PM EDTGale WarningLWX5 hr
Jun 20, 3:24 PM EDTSevere Thunderstorm WarningLWXCharles, Saint Mary's53 min
Jun 20, 3:34 PM EDTTornado WarningLWXHarford26 min
Jun 20, 4:23 PM EDTSevere Thunderstorm WarningLWXHarford37 min

Nearby

Tornado Warnings in Maryland, 2009Every tornado warning in 2009Tornadoes 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.