Alert archive / Virginia / Severe Thunderstorm Warnings in 2004

Severe Thunderstorm Warning 183, NWS Baltimore/Washington

July 7, 2004Loudoun County, Virginia

NWS Baltimore/Washington issued this severe thunderstorm warning at Jul 7, 2004, 7:40 PM EDT for Loudoun County, Virginia. It was in force for 50 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 7, 2004, 7:40 PM EDT (23:40 UTC)
Expired: Jul 7, 2004, 8:30 PM EDT
In force: 50 min
Issued by: NWS Baltimore/Washington
Area: Counties, with a storm outline in the text

County Loudoun County, VA

The radar

The Sterling radar (KLWX), 18 km from the middle of the area, began a volume at 23:40 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 12:00Z, 11.7 hours before the alert went out and 26 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: 455 J/kg
Mixed-layer CIN: -139 J/kg
Mixed-layer LCL: 1252 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 36 m²/s²
0-3 km storm-relative helicity: 73 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

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 7, 6:50 PM EDT, 50 minutes earlier.

Area forecast discussion, Jul 7, 6:50 PM EDT, 50 minutes before

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Hazardous weather outlook, Jul 7, 11:20 AM EDT, 8 hours 20 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1120 AM EDT WED JUL 7 2004

DCZ001-MDZ002>007-009>011-013-014-016>018-VAZ021-025>031-036>042-
050>057-WVZ048>055-080800-
ALBEMARLE VA-ALLEGANY MD-ANNE ARUNDEL MD-
ARLINGTON/FALLS CHURCH/ALEXANDRIA VA-AUGUSTA VA-BERKELEY WV-
CALVERT MD-CARROLL MD-CHARLES MD-CLARKE VA-CULPEPER VA-
DISTRICT OF COLUMBIA DC-FAIRFAX VA-FAUQUIER VA-FREDERICK VA-
FREDERICK MD-GRANT WV-GREENE VA-HAMPSHIRE WV-HARDY WV-HARFORD MD-
HIGHLAND VA-HOWARD MD-JEFFERSON WV-KING GEORGE VA-LOUDOUN VA-
MADISON VA-MINERAL WV-MONTGOMERY MD-MORGAN WV-NELSON VA-
NORTHERN BALTIMORE MD-ORANGE VA-PAGE VA-PENDLETON WV-
PRINCE GEORGES MD-PRINCE WILLIAM/MANASSAS/MANASSAS PARK VA-
RAPPAHANNOCK VA-ROCKINGHAM VA-SHENANDOAH VA-SOUTHERN BALTIMORE MD-
SPOTSYLVANIA VA-ST. MARYS MD-STAFFORD VA-WARREN VA-WASHINGTON MD-
1120 AM EDT WED JUL 7 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MARYLAND WEST OF THE CHESAPEAKE
BAY AND EAST OF GARRETT COUNTY...EASTERN WEST VIRGINIA...NORTHERN AND
CENTRAL VIRGINIA AND WASHINGTON DC.

.DAY ONE...

THE STORM PREDICTION CENTER IN NORMAN OKLAHOMA HAS ISSUED AN OUTLOOK
FOR PORTIONS OF WESTERN VIRGINIA...EASTERN WEST VIRGINA...AND WESTERN
MARYLAND AS HAVING A RISK FOR SEVERE THUNDERSTORMS. THE MOST LIKELY
THREAT WILL BE DAMAGING WINDS IN EXCESS OF 60 MPH AND POSSIBLY LARGE
HAIL. THIS IS MOST LIKELY TO OCCUR BETWEEN 2 AND 7 PM. STORMS WILL
HAVE THE POTENTIAL TO DRIFT FURTHER EAST INTO THE METROPOLITAN AREAS
IN THE LATE AFTERNOON AND EVENING.

.DAYS TWO THROUGH SEVEN...

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED THIS AFTERNOON AND EARLY EVENING.

In the hours before

Local storm report, Jul 7, 5:50 PM EDT, 1 hour 50 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
550 PM EDT WED JUL 07 2004

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

0519 PM     FLASH FLOOD      WOODLAWN                39.31N 76.75W
07/07/2004                   BALTIMORE          MD   COUNTY OFFICIAL

            MANY ROADS CLOSED COUNTYWIDE DUE TO HIGH WATER

&&

RDH

Local storm report, Jul 7, 5:55 PM EDT, 1 hour 45 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
555 PM EDT WED JUL 07 2004

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

0519 PM     FLASH FLOOD      BALTIMORE               39.30N 76.61W
07/07/2004                   BALTIMORE CITY     MD   AMATEUR RADIO

            NUMEROUS ROADS FLOODED IN 21215 ZIP CODE. PARK HEIGHTS
            AVENUE AND REISTERSTOWN ROAD FLOODED. NORTHWEST PART OF
            THE CITY HARDEST HIT.

&&

RDH

Local storm report, Jul 7, 6:03 PM EDT, 1 hour 37 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
603 PM EDT WED JUL 07 2004

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

0427 PM     TSTM WND DMG     BOWIE                   38.96N 76.74W
07/07/2004                   PRINCE GEORGES     MD   FIRE DEPT/RESCUE

            POWERLINES DOWNED IN SEVERAL LOCATIONS.

0445 PM     TSTM WND DMG     FORT MEADE              39.11N 76.74W
07/07/2004                   ANNE ARUNDEL       MD   FIRE DEPT/RESCUE

            MANY TREES AND POWERLINES DOWNED COUNTYWIDE.

0509 PM     TSTM WND DMG     ESSEX                   39.30N 76.45W
07/07/2004                   BALTIMORE          MD   EMERGENCY MNGR

            TREES DOWNED

&&

MANNING

Local storm report, Jul 7, 6:08 PM EDT, 1 hour 32 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
608 PM EDT WED JUL 07 2004

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

0600 PM     FLASH FLOOD      WOODLAWN                39.31N 76.75W
07/07/2004                   BALTIMORE          MD   EMERGENCY MNGR

            WATER RESCUES ONGOING AROUND WESTVIEW. PEOPLE STANDING ON
            TOP OF THEIR VEHICLES.

&&

RDH

Local storm report, Jul 7, 6:26 PM EDT, 1 hour 14 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
626 PM EDT WED JUL 07 2004

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

0505 PM     TSTM WND DMG     BALTIMORE               39.30N 76.61W
07/07/2004                   BALTIMORE CITY     MD   FIRE DEPT/RESCUE

            TREES DOWNED

&&

MANNING

Local storm report, Jul 7, 6:52 PM EDT, 48 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 7, 1:30 PM EDT	Special Marine Warning	LWX		90 min
Jul 7, 1:30 PM EDT	Special Marine Warning	LWX		90 min
Jul 7, 2:27 PM EDT	Severe Thunderstorm Warning	LWX	Fauquier	48 min
Jul 7, 2:31 PM EDT	Special Marine Warning	LWX		29 min
Jul 7, 2:54 PM EDT	Special Marine Warning	LWX		36 min
Jul 7, 2:54 PM EDT	Special Marine Warning	LWX		36 min
Jul 7, 2:58 PM EDT	Special Marine Warning	LWX		92 min
Jul 7, 2:58 PM EDT	Special Marine Warning	LWX		92 min
Jul 7, 3:20 PM EDT	Severe Thunderstorm Warning	LWX	Fairfax, City of Fairfax	40 min
Jul 7, 3:35 PM EDT	Special Marine Warning	LWX		55 min
Jul 7, 4:25 PM EDT	Special Marine Warning	LWX		2 hr
Jul 7, 1:25 PM EDT	Severe Thunderstorm Warning	LWX	Frederick, Washington	50 min
Jul 7, 2:39 PM EDT	Severe Thunderstorm Warning	LWX	Saint Mary's	51 min
Jul 7, 2:51 PM EDT	Severe Thunderstorm Warning	LWX	Anne Arundel	39 min
Jul 7, 2:57 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore, City of Baltimore	63 min
Jul 7, 3:27 PM EDT	Severe Thunderstorm Warning	LWX	Montgomery	48 min
Jul 7, 3:29 PM EDT	Flash Flood Warning	LWX	Baltimore, City of Baltimore	3 hr
Jul 7, 4:19 PM EDT	Severe Thunderstorm Warning	LWX	Prince George's	41 min
Jul 7, 4:34 PM EDT	Severe Thunderstorm Warning	LWX	Anne Arundel	56 min
Jul 7, 4:47 PM EDT	Severe Thunderstorm Warning	LWX	City of Baltimore	43 min
Jul 7, 4:59 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore	46 min
Jul 7, 6:30 PM EDT	Flash Flood Warning	LWX	Baltimore, City of Baltimore	3 hr

Nearby

Severe Thunderstorm Warnings in Virginia, 2004 Every severe thunderstorm warning in 2004

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.