Low pressure and an associated cold front crossed the Mid Atlantic. Ahead of this system, southerly flow transported moisture into the region.
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.
Low pressure and an associated cold front crossed the Mid Atlantic. Ahead of this system, southerly flow transported moisture into the region. Thunderstorm wind damage was the main threat.
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 May 11, 1:33 PM EST, 1 hour 4 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 233 PM EDT SAT MAY 11 2013 .SYNOPSIS... A COLD FRONT OVER WESTERN MARYLAND WILL TRACK TOWARDS THE CHESAPEAKE BAY THIS EVENNG. HIGH PRESSURE WILL BUILD INTO THE MID ATLANTIC REGION SUNDAY THROUGH EARLY NEXT WEEK. HIGH PRESSURE WILL MOVE OFF DURING THE MIDDLE PORTION OF NEXT WEEK. && .NEAR TERM /TONIGHT/... SC CLDS WHICH IMPLIED ATMOSPHERIC STABILITY IN THE MID ATLC THIS MRNG HV LIFTED AND CU DVLPG IN ITS STEAD. QUSTN WL BE HOW MUCH INSTABILITY CAN DVLP E OF THE MTNS AHD OF THE FNT...WHICH IS CLRLY DEFINED ON RGNL RDR XTNDG FM CENTRAL PA THRU WRN MD INTO ERN W.V. BUFKIT SNDGS SHOW CAPE OVR 700 J/KG. IAD VWP STILL NOT LOOKING TOO IMPRESSIVE W/ WINDS L.T. 30 KT UP TO 10K FT. BWI VWP SHOWS WINDS A LTL STRONGER. HRRR SHOWS A LN DVLPG DURG THE NEXT FEW HRS E OF THE MTNS...MOVG ONTO THE ERN SHORE BY 22Z. THE ERN PART OF THE CWA - INCLUDING DC AND BALT...IS OUTLOOKED AS HAVG A SLT RISK OF TSTMS. QUSTN IS GOING TO INVOLVE TIMING - WL LN BE DVLPD ENOUGH BY THE TIME IT GETS TO THE CITIES FOR SVR? AT MOMENT IT SEEMS UNLKLY. YDA I WROTE THAT LWR SRN MD WOULD HV THE BEST CHC FOR SVR WX...AND THAT STILL SEEMS TO BE THE CASE. SKIES CLRG BEHIND THE FNT THIS EVENING. WINDS TURN WNWRLY. DWPTS DROPPING FM THE L60S TO THE U40S. LOW TEMPS IN THE 40S IN THE MTNS...50S E. && .SHORT TERM /SUNDAY/... HIGH PRES BLDS INTO THE RGN TMRW. BRZY CONDS..M SUN SKIES..HIGHS 65-70 E OF THE MTNS...60-65 W. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... WENT WITH GFS BIAS CORRECTED TEMP GRIDS THRU THE PERIOD WHICH HAVE BEEN PERFORMING WELL. UNSEASONABLY LATE COLD SNAP WILL POSE SOME AGRICULTURAL ISSUES EARLY NEXT WEEK. COLD HIGH PRES MOVES IN ON W WINDS SUN NIGHT. FREEZING CONDITIONS CURRENTLY IN THE FORECAST FOR W GRANT AND W PENDLETON COUNTIES IN WV. HIGH PRES CENTERS OVER THE AREA MON NIGHT WHICH WILL ALLOW FOR FROST EARLY TUE MORNING OVER THE SHEN VALLEY...N CENTRAL MD AND POINTS WEST. PATCHY FROST WILL EXTEND EAST OF THE BLUE RIDGE AS WELL...THO THE BALT AND WASH METRO AREAS SHOULD ESCAPE WITH TEMPS IN THE UPPER 30S TO LOWER 40S. PATCHY FROST WILL BE CLOSE BY THOUGH. TUE...MID LEVL WARM FRONT ADVANCES ON AREA FROM MIDWEST BRINGING AN INCREASE IN CLOUDS. EURO AND GFS IN PRETTY GOOD AGREEMENT THROUGH THE UPCOMING WEEK. TUE NIGHT INTO WED THE MID LEVEL WARM FRONT PASSES ENE THRU THE REGION. SHOULD BE DRY BUT 850MB TEMPS RISE FROM THE SINGLE DIGITS TUE EVE TO THE MIDDLE TEENS BY WED EVE. THAT IS QUICKLY FOLLOWED BY A SMALL 500MB TROF THAT DEVELOPS A WEAK LOW OVER THE REGION WITH A TRAILING COLD FRONT LATE THU INTO FRI. A SMALL AREA OF SLIGHTLY COOLER HIGH PRESSURE TRIES TO NOSE IN FROM THE MIDWEST FOR SAT. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... DVLPG LN OF RW/TRW IN ASSO W/ A CD FNT NOW IN WRN MD...APRCHG MRB. CNVCTN WL BE PSBL AT THE AIRPORTS INTO ERLY EVNG. AFTRWARDS HIGH PRES WL BEGIN TO BUILD INTO THE MID ATLC. VFR CONDS XPCTD OVRNGT. SUNDAY NWRLY WINDS WL GUST INTO 20+ KT RANGE DURG DAYLGT HRS. VFR CONDITIONS EXPECTED TUE NIGHT THROUGH SATURDAY...EXCEPT IN ANY SCT TO ISOLATED TSTMS IN THE MID TO LATE WEEK. && .MARINE... SML CRFT ADVSRY HAS BEEN XTND THRU THE RMNDR OF DAYLGT HRS FOR THE WATERS. BUT PRINCIPLE CONCERN FOR NEXT SVRL HRS WL BE TSTMS.. ESPECIALLY THOSE DVLPG IN THE NRN NECK OF VA TRACKING INTO THE CHES BAY. SPL MARINE WRNGS MAY BE REQUIRED. SUNDAY HIGH PRES WL BLD INTO THE WATERS. AN SCA IS IN EFFECT FOR ALL WATERS. SMALL CRAFT ADVISORIES ARE NOT EXPECTED TUE NIGHT THROUGH SATURDAY. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EDT FOR ANZ530>543. SMALL CRAFT ADVISORY FROM 7 AM TO 8 PM EDT SUNDAY FOR ANZ530>543. && PRODUCTS...WOODY!/CAS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 302 PM EDT SAT MAY 11 2013 ANZ530>543-DCZ001-MDZ006-007-011-013-014-016>018-VAZ052>057- 121615- 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- 302 PM EDT SAT MAY 11 2013 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...THIS AFTERNOON AND TONIGHT A SMALL CRAFT ADVISORY IS IN EFFECT FOR PORTIONS OF THE WATERS THROUGH THIS AFTERNOON. SHOWERS AND THUNDERSTORMS ARE EXPECTED AHEAD OF AN APPROACHING COLD FRONT THROUGH THIS EVENING. THUNDERSTORMS LATE THIS AFTERNOON AND EVENING WILL BE CAPABLE OF PRODUCING DAMAGING WIND GUSTS AND LARGE HAIL. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY A SMALL CRAFT ADVISORY IS IN EFFECT FOR THE WATERS SUNDAY. A SMALL CRAFT ADVISORY MAY BE NEEDED FOR THE WATERS MONDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AND EVENING. MDZ003>005-009-010-501-502-VAZ025>031-036>040-042-050-051-501>504- WVZ050>053-055-501>506-121615- 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- 302 PM EDT SAT MAY 11 2013 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...THIS AFTERNOON AND TONIGHT SHOWERS AND THUNDERSTORMS ARE EXPECTED AHEAD OF AN APPROACHING COLD FRONT THROUGH EARLY EVENING. A FEW THUNDERSTORMS MAY BE CAPABLE OF PRODUCING LOCALLY DAMAGING WIND GUSTS...PRIMARILY EAST OF THE BLUE RIDGE. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY AREAS OF FROST WILL BE POSSIBLE IN THE POTOMAC HIGHLANDS SUNDAY NIGHT. WIDESPREAD FROST WILL BE LIKELY WEST OF THE BLUE RIDGE MONDAY NIGHT...WITH SUBFREEZING CONDITIONS POSSIBLE IN THE POTOMAC HIGHLANDS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON.
The Sterling radar (KLWX), 112 km away, was scanning. The volume nearest the first event began at 19:36 UTC.
3 thunderstorm wind. Local standard time, as filed.
There were trees down near intersection of Carrs Mill Road and Wildwood Drive.
There were large trees on a house including a Willow tree.
There were at least ten trees down.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Maryland in 2013Every state in 2013This day in weather historyWarnings in Maryland, May 2013
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: 455917, 455855, 455918.