A surface trough moved into Central VA in the morning as a shortwave trough passed over the region. Showers and thunderstorms formed and produced heavy rain, damaging winds and large hail.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS LWX wrote it up.
A surface trough moved into Central VA in the morning as a shortwave trough passed over the region. Showers and thunderstorms formed and produced heavy rain, damaging winds and large hail.
The local office's own words before the first event, 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 the first event at Sep 6, 2:59 AM EST, 7 hours 1 minute earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 359 AM EDT THU SEP 6 2012 .SYNOPSIS... A WEAK SURFACE TROUGH WILL REMAIN SITUATED ACROSS THE MID-ATLANTIC REGION THROUGH FRIDAY. A COLD FRONT WILL APPROACH THE REGION FRIDAY BEFORE PASSING THROUGH THE AREA SATURDAY. COOLER AND DRIER AIR IS EXPECTED BEHIND THE BOUNDARY FOR THE FIRST HALF OF NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... WSW-ENE ORIENTED SFC TROUGH HAS MOVED INTO CENTRAL VA AND SRN MD ERY THIS MRNG. THE BOUNDARY HAS BECOME INCREASINGLY DIFFUSE. LGT SHOWERS AND SPRINKLES WILL CONTINUE TO OVERSPREAD THE AREA THIS MRNG AS A LOW- AND MID-LVL SHORTWAVE TROUGH APPROACHES FROM THE WEST. ALTHOUGH FORCING IS WEAK...IT WILL NOT TAKE MUCH LIFT TO YIELD SHOWERS GIVEN THE VERY MOIST ENVIRONMENT. HIGHEST COVERAGE OF SHOWERS WILL BE OVER THE SRN POTOMAC HIGHLANDS AND CENTRAL SHENANDOAH VLY...BUT ANY PLACES NEAR AND SOUTH OF THE AFOREMENTIONED TROUGH COULD SEE LGT PRECIP THIS MRNG. THE SFC AND LLVL SHORTWAVE TROUGH WILL PUSH SOUTH AND EAST OF THE CWA BY THE AFTN. SUBSIDENCE IN WAKE OF THE TROUGH SHOULD BE ENOUGH TO CAP CONVECTION OVER MOST OF THE AREA. THE EXCEPTION WILL BE THE POTOMAC HIGHLANDS AS TERRAIN CIRCULATIONS AND STRONG DAYTIME HEATING AID THE DEVELOPMENT OF ISO CONVECTION. A WEAK COLD FRONT THAT IS CURRENTLY OVER THE GREAT LAKES IS FCST TO MOVE INTO THE OH VLY AND CENTRAL PA THIS AFTN. WILL NEED TO MONITOR THE POTENTIAL FOR ADDITIONAL STORMS LATE THIS AFTN/ERY EVE OVER THE HIGHER TERRAIN AND NEAR THE MASON-DIXON LINE AS THE FRONT APPROACHES. A STORM OR TWO MAY BECOME STRONG TO SVR GIVEN THE MODERATELY UNSTABLE ENVIRONMENT AND PRESENCE OF MID-LVL DRY AIR. MAX TEMPS TDA WILL BE SIMILAR TO YDA...UPPER 80S AND LOW 90S... EXCEPT COOLER ALONG THE RIDGE TOPS. COLD FRONT EXPECTED TO BECOME WASHED OUT THIS EVE AS IT APPROACHES THE MASON-DIXON LINE. ANY LEFTOVER SHOWERS AND STORMS SHOULD DISSIPATE BY LATE EVE W/ THE LOSS OF DAYTIME HEATING. MIN TEMPS WILL RANGE FROM NEAR 60 IN THE ALLEGHENY FRONT TO MID 70S IN THE CITIES. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... WEAK LOW PRESSURE TROUGH WILL REMAIN ACROSS THE CWFA DURING THE EARLY PART OF FRIDAY...BUT SHEAR OUT BY THE EVENING AS A COLD FRONT APPROACHES FROM THE WEST. THE FRONT IS EXPECTED TO MOVE THROUGH THE MID ATLANTIC DURING THE DAY ON SATURDAY...ACCOMPANIED BY SHOWERS AND THUNDERSTORMS. A FEW OF THE STORMS COULD BE STRONG...BUT SEVERE WEATHER LOOKS TO BE LIMITED AT THIS TIME. HOWEVER...IF SURFACE INSTABILITY DOES INCREASE...AND GOOD HEATING OCCURS...THE CHANCES FOR SEVERE WEATHER MAY INCREASE. MADE A FEW CHANGES TO THE GRIDS...MAINLY TO THE POPS SURROUNDING THE FRONTAL PASSAGE. OTHERWISE...NO MAJOR CHANGES TO THE REMAINDER OF THE GRIDS. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... HIGH PRESSURE WILL BUILD IN BEHIND THE COLD FRONT LATER ON THE DAY SUNDAY. HOWEVER...A MID LEVEL TROUGH AND STRONG SHORTWAVE WILL MOVE THROUGH DURING THE AFTERNOON. THIS STRONG ENERGY MAY BE ENOUGH TO AID IN THE DEVELOPMENT OF SCATTERED SHOWERS AND THUNDERSTORMS. HIGH PRESSURE REMAINS OVER THE MID ATLANTIC FOR MUCH OF NEXT WEEK. NO CHANGES TO THE GRIDS PAST SUNDAY. && .AVIATION /08Z THURSDAY THROUGH MONDAY/... A SHORTWAVE TROUGH IS CURRENTLY MOVING THRU THE AREA. WITH THE LOW-LEVELS SATURATED...CLOUDS WILL LOWER TO MVFR RANGE AT MOST TERMINALS ERY THIS MRNG. WHILE CLOUDS WILL LIMIT FOG POTENTIAL... VSBYS MAY BE LOCALLY REDUCED TO MVFR LVLS ERY THIS MRNG. ONE EXCEPTION WILL BE CHO...AS CLOUD COVER HAS REMAINED JUST NORTH AND WEST OF THE TERMINAL. IFR RESTRICTIONS FAVORABLE IN FOG. ISO SHOWERS THIS MRNG WILL BE LGT. VFR CONDITIONS AFTER SUNRISE TDA. AN ISO STORM POSSIBLE IN VC OF MRB LATE THIS AFTN. SUB VFR CONDTIONS IN SHOWERS AND THUNDERSTORMS ARE LIKELY ON SATURDAY WITH A COLD FRONTAL PASSAGE. ACTIVITY IS EXPECTED TO BE MORE SCATTERED ON SUNDAY AS A STRONG MID LEVEL DISTURBANCE MOVES THROUGH THE MID ATLANTIC. WINDS WILL SHIFT TO THE N/NW BEHIND THE FRONT ON SUNDAY. && .MARINE... AS OF 3 AM...SFC TROUGH OVER THE MID POTOMAC RVR AND MID CHSPK BAY. SLY WINDS AHEAD OF THE BOUNDARY WILL SHIFT TO NLY ONCE THE BOUNDARY MOVES THRU THIS MRNG. WINDS WILL REMAIN LGT TDA AND TNGT...GENERALLY 5-10 KT. A FEW GUSTS TO 15 KT POSSIBLE TNGT AS SLY WINDS CHANNEL UP THE BAY. ISO SHOWERS LATER THIS MRNG. AN ISO TSTM POSSIBLE OVER THE SRN MOST ZONES OF THE MD CHSPK BAY ERY THIS EVE. A WEAK SURFACE TROUGH WILL REMAIN NEAR THE WATERS THROUGH FRIDAY...BUT SHEAR OUT DURING THE EVENING. A COLD FRONT IS EXPECTED TO IMPACT THE WATERS ON SATURDAY...WITH HIGH PRESSURE BUILDING IN LATE SUNDAY. SPECIAL MARINE WARNINGS ARE POSSIBLE WITH THE SHOWERS AND THUNDERSTORMS THAT WILL ACCOMPANY THE FRONT. HIGH PRESSURE WILL CONTINUE THROUGH MUCH OF NEXT WEEK. SMALL CRAFT CONDITIONS ARE POSSIBLE FRIDAY NIGHT THROUGH MUCH OF SUNDAY. S WINDS ARE EXPECTED TO CHANNEL UP THE BAY AHEAD OF THE COLD FRONT...WITH A NORTHERN SURGE ON SUNDAY BEHIND THE BOUNDARY. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && KLEIN/LISTEMAA
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 508 AM EDT THU SEP 6 2012 ANZ530>543-DCZ001-MDZ006-007-011-013-014-016>018-VAZ052>057- 071000- 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- 508 AM EDT THU SEP 6 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...TODAY AND TONIGHT NO SEVERE WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY A STRONG COLD FRONT WILL CROSS THE MID ATLANTIC ON SATURDAY. THE FRONT WILL BE ACCOMPANIED BY SHOWERS AND THUNDERSTORMS. A FEW OF THE THUNDERSTORMS WILL HAVE THE POTENTIAL TO BECOME SEVERE. SMALL CRAFT CONDITIONS ARE POSSIBLE ACROSS THE WATERS FRIDAY NIGHT THROUGH SUNDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED THROUGH TONIGHT...BUT MAY BE NEEDED ON SATURDAY. MDZ003>005-009-010-501-502-VAZ025>031-036>040-042-050-051-501>504- WVZ050>053-055-501>506-071000- 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- 508 AM EDT THU SEP 6 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...TODAY AND TONIGHT ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS THE POTOMAC HIGHLANDS LATE THIS AFTERNOON. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY A STRONG COLD FRONT WILL CROSS THE MID ATLANTIC ON SATURDAY. THE FRONT WILL BE ACCOMPANIED BY SHOWERS AND THUNDERSTORMS. A FEW OF THE THUNDERSTORMS WILL HAVE THE POTENTIAL TO BECOME SEVERE. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED THROUGH TONIGHT...BUT MAY BE NEEDED ON SATURDAY.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
919 AM EDT THU SEP 06 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0825 AM TSTM WND DMG LOGAN 38.22N 77.76W
09/06/2012 SPOTSYLVANIA VA 911 CALL CENTER
TREE DOWN AT 12000 BLOCK OF WEST CATHARPIN RD
&&
EVENT NUMBER LWX1201162
KLWPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
920 AM EDT THU SEP 06 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0905 AM TSTM WND DMG 4 SSE FREDERICKSBURG 38.25N 77.45W
09/06/2012 SPOTSYLVANIA VA 911 CALL CENTER
TREE DOWN NEAR MINE RD AND LEES CROSSING LANE
&&
EVENT NUMBER LWX1201163
KLWPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1027 AM EDT THU SEP 06 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0900 AM FLASH FLOOD SPOTSYLVANIA 38.20N 77.59W
09/06/2012 SPOTSYLVANIA VA 911 CALL CENTER
PORTION OF WEST CATHARPIN ROAD CLOSED DUE TO FLASH
FLOODING ON CATHARPIN CREEK.
&&
EVENT NUMBER LWX1201164
SBKPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1028 AM EDT THU SEP 06 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1000 AM FLASH FLOOD SPOTSYLVANIA 38.20N 77.59W
09/06/2012 SPOTSYLVANIA VA 911 CALL CENTER
FLASH FLOODING ON JEFFERSON DAVIS HIGHWAY NEAR
MASSAPONAX.
&&
EVENT NUMBER LWX1201165
SBKPRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1033 AM EDT THU SEP 06 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0900 AM FLASH FLOOD 2 E LOGAN 38.22N 77.72W
09/06/2012 SPOTSYLVANIA VA 911 CALL CENTER
PORTION OF WEST CATHARPIN ROAD CLOSED DUE TO FLASH
FLOODING ON CATHARPIN CREEK.
&&
CORRECTED LOCATION
EVENT NUMBER LWX1201164
SBKPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1100 AM EDT THU SEP 06 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0835 AM HAIL 2 WNW COOKSTOWN 38.31N 77.73W
09/06/2012 M0.88 INCH SPOTSYLVANIA VA PUBLIC
PENNY TO NICKEL SIZE HAIL
&&
EVENT NUMBER LWX1201166
KLWThe national radar mosaic for the moment the first event began.
1 flash flood. Local standard time, as filed.
There was flash flooding on Worth Avenue.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Maryland in 2012Every state in 2012This day in weather historyWarnings in Maryland, September 2012
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 413705.