A northwest flow behind a cold front caused cold and moist air to flow over the mountains, triggering snow showers across locations along and west of the Allegheny Front.
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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 northwest flow behind a cold front caused cold and moist air to flow over the mountains, triggering snow showers across locations along and west of the Allegheny Front.
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 Mar 27, 8:53 AM EST, 7 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
953 AM EDT WED MAR 27 2013
.SYNOPSIS...
THE COMBINATION OF LOW PRESSURE TO THE NORTHEAST AND HIGH PRESSURE
TO THE WEST WILL RESULT IN NORTHWEST WINDS ACROSS THE MID-ATLANTIC
THROUGH THURSDAY. HIGH PRESSURE WILL THEN PERSIST THROUGH
SATURDAY. A COLD FRONT LOOKS TO AFFECT THE AREA SUNDAY INTO
MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AFTR MAKING AND RCVG CALLS FM SPOTTERS IN OUR WRN HIGHLANDS WE
FELT WE NEEDED TO REISSUE THE WINT WX ADVSRY AS SNOW CONTINUES TO
ACCUMULATE AT THE HIGHER ELEVS.
SURFACE HIGH PRESSURE WILL REMAIN OVER THE MIDWEST WHILE LOW
PRESSURE REMAINS OVER THE CANADIAN MARITIMES. A NORTHWEST FLOW
BETWEEN THESE TWO SYSTEMS WILL CONTINUE TO BRING CHILLY CONDITIONS
FOR THIS TIME OF YEAR.
A BKN STRATO CU DECK WILL DEVELOP DUE TO THE LIMITED INSTABILITY
ASSOCIATED WITH THE UPPER-LEVEL TROUGH. RAIN/SNOW SHOWERS WILL TRY
TO DEVELOP THIS AFTERNOON AND EVENING...BUT LOW-LEVEL DRY AIR MAY
PREVENT MEASURABLE PRECIP FOR MOST LOCATIONS. HAVE MENTIONED
SPRINKLES AND FLURRIES IN THE FORECAST. SHOULD INSTABILITY BE A BIT
HIGHER THAN ANTICIPATED...THEN POPS MAY NEED TO BE BUMPED UP FOR
RAIN AND SNOW SHOWERS.
MAX TEMPS THIS AFTERNOON WILL RANGE FROM THE 30S IN THE MOUNTAINS TO
THE MIDDLE 50S IN CENTRAL VIRGINIA. MIN TEMPS TONIGHT WILL RANGE
FROM THE TEENS IN THE ALLEGHENY HIGHLANDS TO THE LOWER AND MIDDLE
30S NEAR WASHINGTON AND BALTIMORE.
WIDESPREAD SNOW SHOWERS ARE EXPECTED TONIGHT AS ANOTHER UPPER-
LEVEL DISTURBANCE MOVES THROUGH. ADDITIONAL SNOWFALL ACCUMULATIONS
ARE EXPECTED. A WINTER WEATHER ADVISORY MAY BE NEEDED FOR SOME OF
THESE AREAS.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
THU WILL BE THE LAST OF THE DAILY UPPER VORT PASSAGES DURING THE
MIDDLE PART OF THE WEEK. THIS ONE WILL ACTUALLY BE THE STRONGEST
BUT HAVE LESS LOW LEVEL MOISTURE TO WORK W/ AND WILL MAINLY BE
RESPONSIBLE FOR ANOTHER BREEZY/COOL DAY. EACH DAY THIS WEEK
THOUGH...THE HIGH TEMPS EACH DAY ARE ON A SLOW BUT STEADY
ESCALATOR TOWARD M-U50S BY THE WEEKEND. THU WILL SEE TEMPS
STEADILY CLIMB INTO THE U40S BUT AGAIN HAVE A STIFF NWLY BREEZE
KNOCK THESE LEVELS DOWN A BIT. DEWPOINTS WILL BE IN THE U20S WHICH
WILL HELP TAKE SOME OF THE BITE OUT OF THE AIR THOUGH.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
A LESS IMPACTFUL UPPER WAVE WILL CROSS THE AREA FRI BUT MAINLY
FROM A TRANSITIONAL ZONE BETWEEN THE OFFSHORE LOW AND ONE
APPROACHING FROM THE GREAT LAKES REGION. EITHER WAY...SKIES WILL
CLEAR OUT FOR THE MOST PART AND TEMPS WILL BE ALLOWED TO INCREASE
A COUPLE/FEW DEGREES FROM THE PREVIOUS DAY. WINDS WILL DROP OFF TO
A LIGHT NWLY BREEZE ON FRI AFTN...ALSO HELPING TO MAKE IT FEEL
LIKE A WARMER DAY THAN WE'VE HAD IN A WEEK.
IMPROVEMENT CONTINUES THIS WEEKEND. HIGH PRESSURE WILL INCH ITS WAY
TOWARD THE EAST FROM ITS PLACEMENT OVER THE UPPER MIDWEST THIS
WEEK. DRY CONDITIONS WILL CONTINUE AND THE EXIT OF THE OFFSHORE
LOW PRESSURE SYSTEM WILL BRING TEMPS UP BACK TOWARD AVERAGE LEVELS
FOR THIS TIME OF YEAR...U50S/L60S. A COLD FRONT WILL BE WELL ON
ITS WAY ON SUNDAY MRNG...ON THE DOORSTEP OF THE APLCNS MIDDAY.
BOTH GFS/EC LONG RANGE SOLNS HAVE BEEN MORE PROGRESSIVE SINCE
YESTERDAY BUT ARE BOTH IN AGREEMENT ON THEIR LATEST RUNS TO BRING
IN PRECIP EARLIER IN THE DAY BUT STILL AFTN OR LATER.
THE UPPER LOW RESPONSIBLE FOR THIS SYSTEM WILL THEN DEEPEN OVER
SRN HUDSON BAY...BUT THE FRINGE OF THE SRN STREAM WILL STAY JUST
TO OUR NORTH. AFTER A WARM DAY MON...TEMPS WILL SLIDE INTO THE
50S INTO THE MIDDLE OF NEXT WEEK...W/ ONLY LOW PRECIP CHANCES AS
ANOTHER STORM SYSTEM DEVELOPS OVER THE SOUTHEAST NEXT WEEK.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS ARE EXPECTED THROUGH TONIGHT. NORTHWEST WINDS WILL
GUST AROUND 25 KNOTS...ESPECIALLY LATE THIS MORNING INTO THIS
EVENING. A BKN STRATOCU DECK AROUND 4 TO 5KT IS EXPECTED.
WINDS ON THU WILL BE ABOUT AS BREEZY AS ON WED...MIXING THE
STRONGER BOUNDARY LAYER WINDS TOWARD THE SFC. WINDS WILL SUBSIDE
AND SKIES WILL CLEAR OUT ON FRI. HIGH PRESSURE INTO THE COMING
WEEKEND.
&&
.MARINE...
HIGH PRESSURE WILL REMAIN OVER THE MIDWEST THROUGH TONIGHT WHILE LOW
PRESSURE REMAINS NEAR THE CANADIAN MARITIMES. A NORTHWEST FLOW WILL
CONTINUE DURING THIS TIME. A SMALL CRAFT ADVISORY IS IN EFFECT FOR
THE WATERS TODAY INTO THIS EVENING. THE SMALL CRAFT ADVISORY
CONTINUES THROUGH LATE TONIGHT FOR THE MARYLAND CHESAPEAKE BAY AND
LOWER TIDAL POTOMAC RIVER.
SOLID SCA CONDITIONS FROM DAWN TILL DUSK THU...DISSIPATING
OVERNIGHT. CONDITIONS WILL IMPROVE ON FRI...THOUGH JUST BELOW SCA
RANGE AND A QUIET WEEKEND EXPECTED. A COLD FRONT WILL APPROACH THE
AREA LATE SUN AND BREEZY CONDITIONS COULD RETURN FOR THE EARLY
PART OF NEXT WEEK.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...WINTER WEATHER ADVISORY UNTIL 8 PM EDT THIS EVENING FOR VAZ503.
WV...WINTER WEATHER ADVISORY UNTIL 8 PM EDT THIS EVENING FOR WVZ501-
505.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THURSDAY FOR ANZ530>534-
537>543.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ535.
SMALL CRAFT ADVISORY FROM 8 AM TO 6 PM EDT THURSDAY FOR ANZ535-
536.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ536.
&&
UPDATE...WOODY!
PRVS...BJL/GMSHAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 943 AM EDT WED MAR 27 2013 ANZ530>543-DCZ001-MDZ006-007-011-013-014-016>018-VAZ052>057- 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- 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- 943 AM EDT WED MAR 27 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...TODAY AND TONIGHT A SMALL CRAFT ADVISORY IS IN EFFECT THROUGH THIS EVENING FOR THE WATERS. A SMALL CRAFT ADVISORY IS IN EFFECT OVERNIGHT FOR THE MARYLAND PORTION OF THE CHESAPEAKE BAY AND LOWER TIDAL POTOMAC RIVER FROM COBB ISLAND TO SMITH POINT. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY A SMALL CRAFT ADVISORY IS IN EFFECT THURSDAY FOR THE WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED FOR PORTIONS OF THE WATERS THURSDAY NIGHT AND FRIDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. MDZ003>005-009-010-501-502-VAZ025>031-036>040-042-050-051-501>504- WVZ050>053-055-501>506-281000- 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- 943 AM EDT WED MAR 27 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...TODAY AND TONIGHT A WINTER WEATHER ADVISORY IS IN EFFECT TODAY FOR THE WESTERN SLOPES OF THE POTOMAC HIGHLANDS. ACCUMULATING SNOW WILL CONTINUE TONIGHT ALONG AND WEST OF THE ALLEGHENY AND POTOMAC HIGHLANDS. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY ACCUMULATING SNOW IS EXPECTED ALONG AND WEST OF THE ALLEGHENY FRONT THURSDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.
The national radar mosaic for the moment the first event began.
1 winter weather. Local standard time, as filed.
Snowfall totaled up to 4.0 inches near Mustoe.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Virginia in 2013Every state in 2013This day in weather historyWarnings in Virginia, March 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: 442678.