Alert archive / Maryland / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 41, NWS Baltimore/Washington

May 27, 2007Harford County, Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at May 27, 2007, 7:48 PM EDT for Harford County, Maryland. It was in force for 42 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: May 27, 2007, 7:48 PM EDT (23:48 UTC)
Expired: May 27, 2007, 8:30 PM EDT
In force: 42 min
Issued by: NWS Baltimore/Washington
Area: Counties, with a storm outline in the text

County Harford County, MD

The radar

The Dover AFB radar (KDOX), 108 km from the middle of the area, began a volume at 23:51 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 watch it was issued in

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

Issued	Product	Office	Lasted
May 27, 4:43 PM EDT	Severe Thunderstorm Watch	SPC	4 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 11.8 hours before the alert went out and 115 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: 224 J/kg
Mixed-layer CIN: -196 J/kg
Mixed-layer LCL: 1384 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 9 m²/s²
0-3 km storm-relative helicity: 14 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 May 27, 7:36 PM EDT, 12 minutes earlier.

Area forecast discussion, May 27, 7:36 PM EDT, 12 minutes before

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Hazardous weather outlook, May 27, 1:00 PM EDT, 6 hours 48 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
100 PM EDT SUN MAY 27 2007

ANZ530>537-DCZ001-MDZ003>007-009>011-013-014-016>018-501-502-
VAZ021-025>031-036>042-050>057-WVZ050>055-501>504-281000-
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-
DISTRICT OF COLUMBIA-WASHINGTON-FREDERICK MD-CARROLL-
NORTHERN BALTIMORE-HARFORD-MONTGOMERY-HOWARD-SOUTHERN BALTIMORE-
PRINCE GEORGES-ANNE ARUNDEL-CHARLES-ST. MARYS-CALVERT-
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-PRINCE WILLIAM/MANASSAS/MANASSAS PARK-FAIRFAX-
ARLINGTON/FALLS CHURCH/ALEXANDRIA-STAFFORD-SPOTSYLVANIA-
KING GEORGE-HAMPSHIRE-MORGAN-BERKELEY-JEFFERSON-PENDLETON-HARDY-
WESTERN GRANT-EASTERN GRANT-WESTERN MINERAL-EASTERN MINERAL-
100 PM EDT SUN MAY 27 2007

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

.DAY ONE...THIS AFTERNOON AND TONIGHT

SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP THIS AFTERNOON
ACROSS THE REGION. THE ATMOSPHERE IS VERY MOIST AND UNSTABLE ACROSS
MUCH OF THE REGION. A FEW SEVERE THUNDERSTORMS ARE EXPECTED THIS
AFTERNOON MAINLY BETWEEN 4 AND 8 PM. THE AREA MOST LIKELY TO SEE
SEVERE WEATHER TODAY IS ALONG AND SOUTH OF A LINE FROM BALTIMORE MD
TO HARRISONBURG VIRGINIA. THE PRIMARY RISK FROM ANY SEVERE
THUNDERSTORMS THIS AFTERNOON WILL BE DAMAGING WINDS. LOCALLY HEAVY
RAINFALL IS ALSO POSSIBLE FROM THE STRONGER STORMS.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

THE POTENTIAL FOR ISOLATED SEVERE THUNDERSTORMS WILL CONTINUE
OVER THE REGION IN THE AFTERNOON AND EARLY EVENING EACH DAY
THROUGH THE MIDDLE OF NEXT WEEK. THE BEST CHANCE FOR SEVERE WEATHER
IS EXPECTED ON MONDAY ACROSS THE SHENANDOAH VALLEY AND CENTRAL
VIRGINIA AS A COLD FRONT MOVES THROUGH THE REGION...WITH LESS OF A
CHANCE TUESDAY AND WEDNESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED THIS AFTERNOON AND EARLY EVENING.

MANNING

In the hours before

Local storm report, May 27, 6:58 PM EDT, 50 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
658 PM EDT SUN MAY 27 2007

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

0620 PM     TSTM WND DMG     MCLEAN                  38.94N 77.18W
05/27/2007                   FAIRFAX            VA   COUNTY OFFICIAL

            MULTIPLE REPORTS OF TREES DOWN AROUND THE NORTHERN END OF
            THE COUNTY. 911 CENTER REPORT. ROUTE 7 AND PIMMIT DRIVE
            IN TYSONS CORNER. ALSO CHESTERFIELD AVENUE AND OLD
            DOMINION DRIVE AT FOREST WOOD DRIVE.

&&

HITCHENS

Local storm report, May 27, 7:01 PM EDT, 47 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
701 PM EDT SUN MAY 27 2007

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

0640 PM     TSTM WND DMG     OLNEY                   39.15N 77.08W
05/27/2007                   MONTGOMERY         MD   EMERGENCY MNGR

            ONE TREE DOWN NEAR GEORGIA AVE AND HWY 108.

&&

GMS

Local storm report, May 27, 7:14 PM EDT, 34 minutes before

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Local storm report, May 27, 7:21 PM EDT, 27 minutes before

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Local storm report, May 27, 7:37 PM EDT, 11 minutes before

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Local storm report, May 27, 7:45 PM EDT, 3 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
May 27, 2:28 PM EDT	Severe Thunderstorm Warning	LWX	Albemarle, City of Charlottesville	47 min
May 27, 3:11 PM EDT	Severe Thunderstorm Warning	LWX	Rockingham	49 min
May 27, 3:24 PM EDT	Severe Thunderstorm Warning	LWX	Shenandoah	51 min
May 27, 4:10 PM EDT	Special Marine Warning	LWX		95 min
May 27, 4:10 PM EDT	Severe Thunderstorm Warning	LWX	Page	50 min
May 27, 4:18 PM EDT	Severe Thunderstorm Warning	LWX	Madison	42 min
May 27, 4:27 PM EDT	Severe Thunderstorm Warning	LWX	Warren	48 min
May 27, 4:38 PM EDT	Severe Thunderstorm Warning	LWX	Rappahannock	52 min
May 27, 4:55 PM EDT	Severe Thunderstorm Warning	LWX	Fauquier	51 min
May 27, 5:10 PM EDT	Severe Thunderstorm Warning	LWX	Clarke	31 min
May 27, 5:17 PM EDT	Severe Thunderstorm Warning	LWX	Loudoun	73 min
May 27, 5:19 PM EDT	Severe Thunderstorm Warning	LWX	Prince William, City of Manassas, City of Manassas Park	45 min
May 27, 5:24 PM EDT	Special Marine Warning	LWX		96 min
May 27, 5:51 PM EDT	Severe Thunderstorm Warning	LWX	Fairfax, City of Fairfax, City of Falls Church	54 min
May 27, 6:19 PM EDT	Severe Thunderstorm Warning	LWX	Arlington, City of Alexandria	44 min
May 27, 6:56 PM EDT	Special Marine Warning	LWX		2 hr
May 27, 6:08 PM EDT	Severe Thunderstorm Warning	LWX	Montgomery	53 min
May 27, 6:38 PM EDT	Severe Thunderstorm Warning	LWX	Carroll	67 min
May 27, 6:43 PM EDT	Severe Thunderstorm Warning	LWX	Prince George's	47 min
May 27, 6:55 PM EDT	Severe Thunderstorm Warning	LWX	Harford	50 min
May 27, 7:09 PM EDT	Severe Thunderstorm Warning	LWX	Anne Arundel	51 min
May 27, 7:11 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore	49 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2007 Every severe thunderstorm warning in 2007

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.