Alert archive / Maryland / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 156, NWS Baltimore/Washington

July 5, 2012Charles County, Saint Mary's County, Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at Jul 5, 2012, 3:46 AM EDT for Charles County, Saint Mary's County, Maryland. It was in force for 22 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 5, 2012, 3:46 AM EDT (07:46 UTC)
Expired: Jul 5, 2012, 4:08 AM EDT
In force: 22 min
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon

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

The radar

The Sterling radar (KLWX), 94 km from the middle of the area, began a volume at 07:46 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, 7.8 hours before the alert went out and 87 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: 2993 J/kg
Mixed-layer CIN: -17 J/kg
Mixed-layer LCL: 1701 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 27 m²/s²
0-3 km storm-relative helicity: 107 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 5, 3:39 AM EDT, 7 minutes earlier.

Area forecast discussion, Jul 5, 3:39 AM EDT, 7 minutes before

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Hazardous weather outlook, Jul 5, 2:21 AM EDT, 1 hour 25 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
221 AM EDT THU JUL 5 2012

ANZ530>543-DCZ001-MDZ006-007-011-013-014-016>018-VAZ052>057-
060930-
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-
221 AM EDT THU JUL 5 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

ISOLATED THUNDERSTORMS MAY DEVELOP OVERNIGHT WHICH COULD REQUIRE WARNINGS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

HEAT INDICES OVER 100 DEGREES ARE EXPECTED TODAY THROUGH SATURDAY.
HEAT ADVISORIES ARE EXPECTED DURING THIS TIME. SATURDAY SHOULD BE THE
HOTTEST DAY...WITH HEAT INDICES NEAR 110 DEGREES IN THE URBAN
CORRIDOR. AN EXCESSIVE HEAT WATCH MAY BE REQUIRED FOR SATURDAY.

SEVERE THUNDERSTORMS ARE POSSIBLE SUNDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED OVERNIGHT.

MDZ003>005-009-010-501-502-VAZ025>031-036>040-042-050-051-501>504-
WVZ050>053-055-501>506-060930-
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-
221 AM EDT THU JUL 5 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

ISOLATED THUNDERSTORMS MAY DEVELOP OVERNIGHT WHICH COULD REQUIRE WARNINGS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

EAST OF THE ALLEGHENY AND POTOMAC HIGHLANDS...HEAT INDICES OVER
100 DEGREES ARE POSSIBLE TODAY AND FRIDAY. HEAT ADVISORIES MAY BE
NEEDED DURING THIS TIME.

HEAT INDICES NEAR 110 DEGREES ARE POSSIBLE SATURDAY IN THE URBAN
CORRIDOR...AND AN EXCESSIVE HEAT WATCH MAY BE REQUIRED. ELSEWHERE...
A HEAT ADVISORY MAY BE NEEDED SATURDAY.

SEVERE THUNDERSTORMS ARE POSSIBLE SUNDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED OVERNIGHT.

In the hours before

Local storm report, Jul 4, 11:15 PM EDT, 4 hours 31 minutes before

PRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1115 PM EDT WED JUL 04 2012

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

0957 PM     TSTM WND DMG     2 NNE ASHVILLE          38.89N  77.91W
07/04/2012                   FAUQUIER           VA   911 CALL CENTER

            TREE DOWN NEAR GROVE LANE NEAR ASHVILLE DUE TO STRONG
            THUNDERSTORM WINDS.

&&

CORRECTED REMARKS

EVENT NUMBER LWX1200810

CJL

Local storm report, Jul 4, 11:20 PM EDT, 4 hours 26 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1120 PM EDT WED JUL 04 2012

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

1006 PM     TSTM WND DMG     MARSHALL                38.87N  77.84W
07/04/2012                   FAUQUIER           VA   911 CALL CENTER

            TREE DOWN NEAR EAST MAIN ST AND WINCHESTER ROAD NEAR
            MARSHALL DUE TO STRONG THUNDERSTORM WINDS.

&&

EVENT NUMBER LWX1200812

CJL

Special weather statement, Jul 5, 2:15 AM EDT, 1 hour 31 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
215 AM EDT THU JUL 5 2012

VAZ051-055-056-502-050700-
CULPEPER VA-SOUTHERN FAUQUIER VA-STAFFORD VA-SPOTSYLVANIA VA-
215 AM EDT THU JUL 5 2012

...STRONG THUNDERSTORM TO AFFECT CULPEPER...SOUTHERN FAUQUIER...
STAFFORD AND SPOTSYLVANIA COUNTIES...

AT 215 AM EDT...A STRONG THUNDERSTORM WAS LOCATED 2 MILES SOUTHWEST
OF SOMERVILLE...MOVING SOUTHEAST AT 15 MPH.

LOCATIONS IMPACTED INCLUDE HEFLIN...STORCK...RUBY...SHILOH...
HARTWOOD...ROSEVILLE...GLENDIE...RAMOTH AND GARRISONVILLE.

THIS STORM IS PRODUCING FREQUENT CLOUD TO GROUND LIGHTNING. MOVE
INDOORS IMMEDIATELY FOR YOUR SAFETY. IF YOU CAN HEAR THUNDER...YOU
ARE CLOSE ENOUGH TO BE STRUCK BY LIGHTNING.

HEAVY RAIN WITH THIS STORM WILL REDUCE VISIBILITIES TO BELOW ONE MILE
AND MAY CAUSE PONDING OF WATER ON ROADWAYS.

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

&&

LAT...LON 3848 7739 3829 7757 3842 7780 3860 7765
TIME...MOT...LOC 0615Z 294DEG 11KT 3850 7763

KONARIK

Local storm report, Jul 5, 3:08 AM EDT, 38 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
308 AM EDT THU JUL 05 2012

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

0253 AM     TSTM WND GST     1 SW QUANTICO           38.51N  77.30W
07/05/2012  M61 MPH          PRINCE WILLIAM     VA   AWOS

&&

EVENT NUMBER LWX1200813

SBK

Local storm report, Jul 5, 3:15 AM EDT, 31 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
315 AM EDT THU JUL 05 2012

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

0302 AM     TSTM WND GST     1 SW QUANTICO           38.51N  77.30W
07/05/2012  M68 MPH          PRINCE WILLIAM     VA   AWOS

&&

EVENT NUMBER LWX1200814

SBK

Special weather statement, Jul 5, 3:36 AM EDT, 10 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 4, 8:20 PM EDT	Severe Thunderstorm Warning	LWX	Frederick	40 min
Jul 4, 8:31 PM EDT	Severe Thunderstorm Warning	LWX	Frederick, Shenandoah	29 min
Jul 4, 8:53 PM EDT	Severe Thunderstorm Warning	LWX	Clarke, Frederick, Warren, City of Winchester	52 min
Jul 4, 8:59 PM EDT	Severe Thunderstorm Warning	LWX	Frederick, Page, Shenandoah, Warren	46 min
Jul 4, 9:34 PM EDT	Severe Thunderstorm Warning	LWX	Clarke, Culpeper, Fauquier, Loudoun, Prince William, Rappahannock and 1 more	41 min
Jul 4, 9:42 PM EDT	Special Weather Statement	LWX	Loudoun	33 min
Jul 4, 10:00 PM EDT	Severe Thunderstorm Warning	LWX	Fairfax, Fauquier, Loudoun, Prince William	45 min
Jul 4, 10:05 PM EDT	Severe Thunderstorm Warning	LWX	Culpeper, Fauquier, Prince William, Rappahannock, City of Manassas	40 min
Jul 4, 10:09 PM EDT	Special Marine Warning	LWX		111 min
Jul 4, 10:12 PM EDT	Special Marine Warning	LWX		109 min
Jul 4, 10:31 PM EDT	Special Marine Warning	LWX		92 min
Jul 4, 10:43 PM EDT	Special Weather Statement	LWX	Fairfax, Prince William, City of Fairfax, City of Manassas, City of Manassas Park	32 min
Jul 5, 2:15 AM EDT	Special Weather Statement	LWX	Stafford	45 min
Jul 5, 2:30 AM EDT	Severe Thunderstorm Warning	LWX	Fauquier, Prince William, Stafford	45 min
Jul 5, 2:39 AM EDT	Special Marine Warning	LWX		96 min
Jul 5, 2:48 AM EDT	Severe Thunderstorm Warning	LWX	Prince William, Stafford	42 min
Jul 5, 3:25 AM EDT	Severe Thunderstorm Warning	LWX	King George	39 min
Jul 5, 3:28 AM EDT	Special Marine Warning	LWX		60 min
Jul 5, 3:45 AM EDT	Heat Advisory	LWX	Arlington, Culpeper, Fairfax, Fauquier, Greene, King George and 11 more	16 hr
Jul 5, 1:14 PM EDT	Small Craft Advisory	LWX		5 hr
Jul 5, 7:24 PM EDT	Special Marine Warning	LWX		72 min
Jul 5, 4:08 AM EDT	Special Weather Statement	LWX	Charles	52 min
Jul 5, 1:43 PM EDT	Excessive Heat Warning	LWX	Baltimore, City of Baltimore	6 hr
Jul 5, 6:20 PM EDT	Special Weather Statement	LWX	Baltimore	25 min
Jul 5, 6:39 PM EDT	Special Weather Statement	LWX	Baltimore	31 min
Jul 5, 7:08 PM EDT	Special Weather Statement	LWX	Carroll	32 min
Jul 5, 7:42 PM EDT	Special Weather Statement	LWX	Baltimore	33 min
Jul 5, 3:36 AM EDT	Special Weather Statement	LWX	Grant	54 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2012 Every 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.