Alert archive / Maryland / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 222, NWS Baltimore/Washington

July 19, 2012Anne Arundel County, Calvert County, Prince George's County, Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at Jul 19, 2012, 11:16 PM EDT for Anne Arundel County, Calvert County, Prince George's 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
Jul 19, 2012, 11:16 PM EDT (03:16 UTC)
Expired
Jul 19, 2012, 11:45 PM EDT
In force
29 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon

Counties Anne Arundel County, MD, Calvert County, MD, Prince George's County, MD

The radar

The Sterling radar (KLWX), 76 km from the middle of the area, began a volume at 03:17 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 nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 3.3 hours before the alert went out and 68 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 00:00Z on 2012-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 525 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 00:00Z on 2012-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 4 square meters per square second.1939Sfc1 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
525 J/kg
Mixed-layer CIN
-20 J/kg
Mixed-layer LCL
1690 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
4 m²/s²
0-3 km storm-relative helicity
47 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 Jul 19, 10:29 PM EDT, 47 minutes earlier.

Area forecast discussion, Jul 19, 10:29 PM EDT, 47 minutes before
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Hazardous weather outlook, Jul 19, 7:34 PM EDT, 3 hours 42 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
734 PM EDT THU JUL 19 2012

ANZ530>543-DCZ001-MDZ006-007-011-013-014-016>018-VAZ052>057-
200945-
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-
734 PM EDT THU JUL 19 2012

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

THUNDERSTORMS ARE EXPECTED THIS EVENING. A FEW OF THE STORMS MAY
BE SEVERE...PRODUCING DAMAGING WIND GUSTS. LOCALLY HEAVY RAINFALL
COULD ALSO LEAD TO FLASH FLOODING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

ISOLATED STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE FRIDAY
AFTERNOON AND EVENING.

.SPOTTER INFORMATION STATEMENT...

SKYWARN ACTIVATION COULD BECOME NECESSARY THIS EVENING. LIMITED
ACTIVATION IS ALSO POSSIBLE ON FRIDAY.

MDZ003>005-009-010-501-502-VAZ025>031-036>040-042-050-051-501>504-
WVZ050>053-055-501>506-200945-
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-
734 PM EDT THU JUL 19 2012

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

THUNDERSTORMS ARE EXPECTED THIS EVENING. A FEW OF THE STORMS MAY
BE SEVERE...PRODUCING DAMAGING WIND GUSTS. LOCALLY HEAVY RAINFALL
COULD ALSO LEAD TO FLASH FLOODING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

ISOLATED STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE FRIDAY
AFTERNOON AND EVENING.

.SPOTTER INFORMATION STATEMENT...

SKYWARN ACTIVATION COULD BECOME NECESSARY THIS EVENING. LIMITED
ACTIVATION IS ALSO POSSIBLE ON FRIDAY.

In the hours before

Local storm report, Jul 19, 10:16 PM EDT, 1 hour before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1016 PM EDT THU JUL 19 2012

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

1012 PM     FLOOD            1 NE WESTMINSTER        39.59N  77.00W
07/19/2012                   CARROLL            MD   PUBLIC

            WATER ESTIMATED 1 TO 2 FEET DEEP IN SPOTS COVERING EAST
            BOUND LANE ON MD RT 140 AT MD RT 97.

&&

EVENT NUMBER LWX1200950

KLW
Local storm report, Jul 19, 10:17 PM EDT, 59 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1017 PM EDT THU JUL 19 2012

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

0720 PM     FLASH FLOOD      1 N FELLS POINT         39.29N  76.58W
07/19/2012                   BALTIMORE CITY     MD   BROADCAST MEDIA

            2 FEET OF WATER FLOWING DOWN NORTH KENWOOD AVE

&&

EVENT NUMBER LWX1200951

WOODY!
Special weather statement, Jul 19, 10:20 PM EDT, 56 minutes before
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Local storm report, Jul 19, 10:37 PM EDT, 39 minutes before
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Special weather statement, Jul 19, 10:45 PM EDT, 31 minutes before
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Local storm report, Jul 19, 11:08 PM EDT, 8 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Jul 19, 8:43 PM EDTSpecial Weather StatementLWXLoudoun47 min
Jul 19, 9:07 PM EDTSpecial Marine WarningLWX83 min
Jul 19, 9:16 PM EDTSpecial Marine WarningLWX38 min
Jul 19, 9:28 PM EDTSpecial Weather StatementLWXArlington, Fairfax, City of Alexandria, City of Fairfax, City of Falls Church, City of Manassas and 1 more47 min
Jul 19, 9:34 PM EDTSevere Thunderstorm WarningLWXArlington, Fairfax, Prince William, City of Alexandria, City of Fairfax, City of Falls Church and 1 more41 min
Jul 19, 9:58 PM EDTSpecial Marine WarningLWX92 min
Jul 19, 10:20 PM EDTSpecial Weather StatementLWXCity of Alexandria25 min
Jul 19, 10:24 PM EDTFlash Flood WarningLWXArlington, City of Alexandria3 hr
Jul 19, 10:26 PM EDTSpecial Marine WarningLWX25 min
Jul 19, 10:31 PM EDTSpecial Marine WarningLWX82 min
Jul 19, 10:36 PM EDTSpecial Marine WarningLWX114 min
Jul 19, 11:04 PM EDTSpecial Marine WarningLWX86 min
Jul 19, 11:07 PM EDTSpecial Marine WarningLWX78 min
Jul 20, 4:26 AM EDTFlash Flood WatchLWXArlington, Clarke, Culpeper, Fairfax, Fauquier, Frederick and 22 more17 hr
Jul 20, 7:11 PM EDTSpecial Weather StatementLWXCity of Manassas Park49 min
Jul 20, 7:44 PM EDTFlash Flood WarningLWXFairfax, Fauquier, Loudoun, Prince William85 min
Jul 19, 9:20 PM EDTSevere Thunderstorm WarningLWXFrederick, Howard, Montgomery, Prince George's40 min
Jul 19, 9:49 PM EDTSpecial Weather StatementLWXHoward26 min
Jul 19, 10:01 PM EDTSpecial Weather StatementLWXHoward29 min
Jul 19, 10:06 PM EDTFlash Flood WarningLWXAnne Arundel, Baltimore, City of Baltimore3 hr
Jul 19, 10:17 PM EDTFlash Flood WarningLWXBaltimore, Carroll3 hr
Jul 19, 10:45 PM EDTSpecial Weather StatementLWXAnne Arundel, Prince George's45 min
Jul 20, 1:06 AM EDTSpecial Weather StatementLWXCity of Baltimore24 min
Jul 20, 3:36 PM EDTSpecial Weather StatementLWXAllegany39 min
Jul 20, 6:19 PM EDTSpecial Weather StatementLWXGrant, Hardy41 min
Jul 20, 6:59 PM EDTSpecial Weather StatementLWXHardy46 min
Jul 20, 7:03 PM EDTFlash Flood WarningLWXGrant, Hardy, Pendleton115 min

Nearby

Severe Thunderstorm Warnings in Maryland, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.