A wave of low pressure passed by to the south during the 9th. The low triggered a period of wintry precipitation across central Maryland.
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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 wave of low pressure passed by to the south during the 9th. The low triggered a period of wintry precipitation across central Maryland.
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 Jan 9, 10:12 AM EST, 1 hour 48 minutes earlier.
AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 1012 AM EST MON JAN 9 2012 .SYNOPSIS... LOW PRESSURE WILL MOVE ACROSS NORTH CAROLINA WHILE HIGH PRESSURE OVER THE MID-ATLANTIC REGION SHIFTS EASTWARD. HIGH PRESSURE RETURNS TUESDAY. A STORM SYSTEM WILL IMPACT THE MID-ATLANTIC REGION WEDNESDAY AND WEDNESDAY NIGHT. A STRONG COLD FRONT IS EXPECTED TO CROSS THE REGION ON THURSDAY...USHERING IN MUCH COLDER AIR TO THE REGION. && .NEAR TERM /THROUGH TUESDAY/... SFC HIPRES NOTED OVER MID-ATLC RGN TDA BENEATH QUASI-ZONAL FLOW ALOFT. SHRTWV TROF OVER WRN GRTLKS RGN THIS MRNG WILL RACE SEWD TO THE APLCNS BY THIS EVE. SFC LOPRES WILL CROSS THE CAROLINAS THIS AFTN AND EMERGE INTO THE ATLC THIS EVE. MODEST WARM AIR ADVCTN ALOFT IS GENERATING LGT PCPN THIS MRNG IN FAR SWRN ZONES. REPORTS EARLY THIS MRNG FROM HIGHLAND CTY NOTED ICY ROADS AT HIGHER ELEVATIONS OWING TO FRZG DRZL. RECENT OBS HAVE INDICATED THAT PCPN MAY HAVE CHGD TO BRIEF LGT SNOW. ADZY WAS EXTENDED UNTIL 12PM FOR ANY LINGERING FRZG DRZL. BY THE TIME MEASURABLE PCPN ARRIVES...SFC TEMPS SHOULD BE ABV FRZG...SO NO ADDITIONAL HEADLINES XPCD. RAIN XPCD TO INCR THIS AFTN WITH APRCH OF UPR SHRTWV TROF...SPCLY ACRS SRN ZONES...WHERE UP TO ONE-TENTH INCH WILL BE PSBL THRU THIS EVE. RAPID CLRG XPCD TNGT IN WAKE OF SHRTWV TROF. TUE WILL BE MOSTLY SUNNY AS HIPRES BUILDS INTO THE RGN AT THE SFC AND WINDS BCM WLY. AFTER A COOL DAY IN THE LOW 40S TDA...MAXIMA ON TUE WILL REBOUND INTO THE LOW- MID 50S. NO PCPN XPCD. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... ABOUT A DAY REPRIEVE IN BETWEEN THE EXITING UPPER LEVEL WAVE AND THE NEXT LOW PRESSURE SYSTEM TO AFFECT THE REGION. THIS FEATURE IS CURRENTLY AN UPPER LOW OVER THE W TX PANHANDLE. THIS CUT OFF UPPER LOW WILL ACTUALLY MAINTAIN GOOD ORGANIZATION AND ACTUALLY DEEPEN AS IT DRIFTS DUE EWD OVER THE I-20 CORRIDOR OF THE DEEP SOUTH TUE/WED. WHILE CROSSING OVER THESE STATES...THE SYSTEM WILL PICK UP A HEFTY FETCH OF GULF MOISTURE AND BEGIN TO MAKE A DIRECT PATH UP THE ERN SEABOARD EARLY WED. THIS SYSTEM WILL MAINTAIN RELATIVELY WARM CHARACTERISTICS DRIFTING UP TOWARD AND OVER THE MID ATLC WED/THU. MUCH OF THE QPF WILL BE CLOSER TO THE COAST...BUT A LARGE LIGHT TO MODERATE SHIELD OF RAIN WILL BE PUSHING UP THE PIEDMONT AND COASTAL AREAS OF THE CWA DURING THE DAYTIME HRS ON WED AND INTO THE LATE NIGHT HRS. MEANWHILE...A DEEP UPPER TROF WILL BE DIGGING DOWN THE WRN SIDE OF THE GREAT LAKES AND INTO THE MID MS VLY. THIS WILL SQUEEZE THE SOUTHEAST CUT-OFF LOW QUICKLY UP THE ERN SEABOARD AND BRING IN COLDER/DRIER AIR. AS THE LOW RACES TOWARD NEW ENGLAND...THIS COLDER REGIME WILL BEGIN TO CHANGEOVER ANY LINGERING PRECIP TO SNOW /MAINLY ACROSS THE MTNS BUT POTENTIALLY SOME BRIEF PATCHES OF RAIN-SNOW MIX BACK INTO THE SHENANDOAH VLY/PIEDMONT EARLY THU MRNG. BEFORE THE BACKSIDE UPPER TROF REACHES THE AREA LATE THU...WE WILL SEE ANOTHER 3-DAY STRETCH OF WELL-ABOVE NORMAL TEMPS /THOUGH PERIODS OF RAIN WILL BE FALLING FOR ABOUT HALF THAT STRETCH/. && .LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/... A COUPLE OF REINFORCING SURGES OF COLD/DRY AIR WILL SLIDE ACROSS THE MID ATLC TO CLOSE OUT THE WEEK. MAINLY DRY E OF THE MTNS /AND SOME PERIODS OF UPSLOPE SNOW FOR THE WINDWARD SIDES OF THE APLCNS/. THE SECOND SURGE MAY ENCOMPASS THE WEEKEND...KEEPING CONDITIONS BREEZY...DRY AND COLD. && .AVIATION /15Z MONDAY THROUGH FRIDAY/... LGT PCPN WILL SPREAD NEWD TDA AND COULD IMPACT SVRL TERMINALS... INCLUDING KCHO...KIAD AND KDCA. MVFR CIGS PSBL IN ANY PCPN. RAPID CLRG XPCD TNGT AS UPR SHRTWV TROF EXITS RGN. LGT WINDS AND VFR CONDS XPCD THRU RMNDR OF VALID TAF PD. A LOW PRESSURE SYSTEM WILL QUICKLY SLIDE UP ACROSS THE AREA FROM THE SW...FROM MIDDAY WED THROUGH MIDDAY THU. MAINLY PERIODS OF RAIN W/ BREEZY LOW LEVEL WINDS CLOSER TO THE MD BAY/DELMARVA. THE LOW WILL MOVE NE ON THU...W/ A COUPLE OF BREEZY AND DRY UPPER LEVEL SYSTEMS READY TO MOVE DOWN ACROSS THE REGION TO END THE WEEK. && .MARINE... LGT WINDS UP TO 10 KT XPCD ON WATERS TDA AS SFC HIPRES RMNS IN THE RGN. LGT SLY WINDS WILL ENSUE TNGT WHEN HIPRES MOVES EWD INTO ATLC. WINDS WILL BCM WLY BY MRNG. NO HAZARDS ANTICIPATED THRU TUE. CONDITIONS WILL BRIEFLY SETTLE DOWN INTO MIDDAY WED. A LOW PRESSURE SYSTEM WILL MOVE UP THE ERN SEABOARD WED INTO THU...W/ A THE SFC LOW SLIDING JUST SE OF THE I-95 CORRIDOR. THIS WILL BRIEFLY DEVELOP SCA CONDITIONS OVER THE MD BAY/TP LATE WED INTO THU. THIS RAINY SYSTEM WILL RACE TOWARD NEW ENGLAND EARLY THU...WHILE A COUPLE OF DRY AND BREEZY UPPER WAVES GEAR UP TO SWING OVER THE AREA. THESE UPPER LEVEL FEATURES WILL BRING SCA CONDITIONS TO THE AREA TO END THE WEEK. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR VAZ503-504. WV...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR WVZ505-506. MARINE...NONE. && UPDATE...KRAMAR PREV DISCUSSION...WOODY!/GMS
HAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 927 AM EST MON JAN 9 2012 ANZ530>543-DCZ001-MDZ006-007-011-013-014-016>018-VAZ052>057- 101000- 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- 927 AM EST MON JAN 9 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 HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY A SMALL CRAFT ADVISORY MAY BE NEEDED WEDNESDAY NIGHT THROUGH 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>506-101000- 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- 927 AM EST MON JAN 9 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 A WINTER WEATHER ADVISORY FOR FREEZING DRIZZLE AND LIGHT SNOW IS IN EFFECT UNTIL 12 PM FOR HIGHLAND AND PENDLETON COUNTIES. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY ACCUMULATING SNOW WILL BE POSSIBLE LATE IN THE WEEK ALONG WEST- FACING SLOPES OF THE ALLEGHENY FRONT. .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE REQUESTED TO RELAY REPORTS OF FREEZING DRIZZLE OR FREEZING RAIN TO THE NATIONAL WEATHER SERVICE. KRAMAR
The national radar mosaic for the moment the first event began.
2 winter weather. Local standard time, as filed.
Snowfall averaged between one and two inches across the county.
Snowfall averaged around one inch across the county.
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, January 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: 362182, 362183.