Heavy, wet snow on the backside of a slow-moving cold front accumulated 7 to 14 inches across north-central Pennsylvania. Colder air moved into the area from the west behind the front and changed precipitation from rain to snow during the late morning and early afternoon on the 6th.
Every event with a place to put it; 13 filed by county or forecast zone are drawn at its center, in a lighter ring. 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 CTP wrote it up.
Heavy, wet snow on the backside of a slow-moving cold front accumulated 7 to 14 inches across north-central Pennsylvania. Colder air moved into the area from the west behind the front and changed precipitation from rain to snow during the late morning and early afternoon on the 6th. The snow ended by daybreak on the 7th. Intense snowfall rates of 1 inch per hour were common throughout the event. The highest snowfall amounts in excess of 10 inches were found over Tioga, Northern Lycoming and Sullivan Counties. The heavy, wet snow caused some minor damage to trees and wires.
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 State College, PA wrote its last area forecast discussion before the first event at Mar 6, 7:53 AM EST, 2 hours 7 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 753 AM EST SUN MAR 6 2011 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH TODAY...AND DROP TEMPERATURES QUICKLY. THIS WILL TURN THE MODERATE TO HEAVY RAIN TO SNOW OVER THE NORTHERN AND WESTERN HALF OF THE STATE. COOLER AND DRIER CONDITIONS WILL FOLLOW FOR MONDAY AND TUESDAY...AS COLD CANADIAN HIGH PRESSURE BUILDS SOUTHWARD FROM QUEBEC. ANOTHER RAIN STORM IS POSSIBLE FOR LATE WEDNESDAY INTO THURSDAY. && .NEAR TERM /THROUGH TONIGHT/... COMPLEX SITUATION UNDERWAY. WILL KEEP IT BRIEF. NUM GUID IS VERY SIMILAR...SO HAVE HIGHER THAN AVG CONFIDENCE. COLD FRONT ALREADY THRU THE NWRN 3 COS AND ALMOST TO CLEARFIELD/COUDERSPORT. IT WILL CONTINUE SLIDING EASTWARD...DROPPING THE TEMPS QUICKLY INTO THE 30S. WHILE THE RAIN HAS BEEN LIGHT OVER MUCH OF THE AREA...UP TO AN INCH OR INCH AND A HALF IS ALREADY ON THE GROUND IN THE NW...WHERE A CHANGE TO SNOW HAS BEGUN. IT SHOULD GET HEAVIER IN THE SERN HALF AS THE DAY CONTINUES. STORM TOTAL QPF OF 1-2 INCHES STILL LOOKS SOLID. SE MAY NOT CHANGE TO A MIX UNTIL IT BEGINS TO TAPER OFF THIS EVENING. EXPECT THE CHANGEOVER TO OCCUR GRADUALLY THIS MORNING AND EARLY THIS AFTERNOON OVER MUCH OF THE AREA. HAVE POSTED WINT WX/SNOW ADVISORIES AND WARNINGS FOR THE NRN HALF...WITH HIGHEST AMOUNTS OF 6-8 INCHES EXPECTED IN THE NE...WHERE SNOW WILL LINGER INTO THE NIGHT. AROUND 2 INCHES POSS IN STATE COLLEGE AND WILLIAMSPORT. SOME MIX IS EXPECTED AS THE CHANGE OCCURS...WITH PATCHES OF FZRA POSSIBLE. WILL JUST MENTION FOR THE TIME BEING. MOST OF THE ICE WOULD OCCUR IN THE ADVY/WARN AREAS. IF A GLAZE OF ICE BECOMES MORE- POSSIBLE...LATER SHIFTS MAY HAVE TO EXPAND THE ADVY TO THE SOUTH DUE TO THE FZRA...BUT PROBABLY NOT THE SNOW. FLOOD WATCH CONTINUES...AND SMALLER STREAMS ARE HIGH. HOWEVER...THE NEW GUID FROM THE RFCS KEEPS MOST RIVER FORECAST POINTS UNDER FLOOD FOR TODAY. WILL ALLOW THE DAYSHIFT TO GATHER NEWER DATA BEFORE POSTING ANY MORE WARNINGS - AS MORE RAIN WILL BE ON THE GROUND LATER TODAY AND MORE-CERTAIN FORECASTS WILL SURELY FOLLOW. WILL MENTION MANY POINTS IN RVS THIS MORNING. SNOW TAPERS OFF LATE THIS AFTN IN THE WEST AND AROUND MIDNIGHT OR SLIGHTLY LATER IN THE FAR NE. TEMPS CONTINUE TO FALL AND BY MON MORNING...SINGLE DIGITS ARE POSSIBLE OVER THE NEW SNOWPACK IN THE NORTH. && .SHORT TERM /MONDAY THROUGH MONDAY NIGHT/... EXPECT PCPN TO BE ALL DONE BY MONDAY MORNING AS WEEKEND WEATHER SYSTEM EXITS EAST AND HIGH PRESSURE SINKS SOUTH INTO PA FROM EASTERN CANADA. A FEW LINGERING SNOW SHOWERS/FLURRIES ARE POSSIBLE ACROSS NERN ZONES BEFORE MIDDAY...BUT OTHERWISE HIGH PRESSURE WILL LEAD TO CLEARING SKIES DURING THE DAY AND KEEP POPS MINIMAL INTO AT LEAST TUESDAY. && .LONG TERM /TUESDAY THROUGH SATURDAY/... THE NEXT SYSTEM LOOKS TO MOVE INTO THE REGION LATE WEDNESDAY. THE GFS AND EUROPEAN CONTINUE TO SPEED UP THE TIMING. THIS SYSTEM LOOKS TO BE A MIXED PRECIP EVENT WITH MOSTLY RAIN BUT A MIX AS COLD AIR ADVECTS BEHIND AND THEN A PERIOD OF SNOW. THE EC KEEPS THE LOW MORE NORTHWARD WHERE THE GFS BRINGS THE LOW ALONG THE NY AND PA BORDER. THERE DOES LOOK TO BE AMPLE MOISTURE WITH THIS SYSTEM. AFTER A BRIEF DRYING CONDITIONS THERE MAY BE ANOTHER WEAK SYSTEM SATURDAY NIGHT INTO SUNDAY. TEMPERATURES SHOULD BE COOLER THIS WEEK DUE TO THE NORTHWESTERLY FLOW. && .AVIATION /13Z SUNDAY THROUGH THURSDAY/... COLD FRONT IS MOVING SLOWLY EAST THROUGH CENTRAL PA AT THIS TIME. IFR/LIFR IN PCPN AND CIGS WILL SPREAD EAST OVER THE MORNING HOURS. WIDESPREAD LOW CIGS/VSBYS ARE EXPECTED WITH RAIN FALLING HEAVILY AT TIMES. CHANGEOVER TO SNOW AND WIND SHIFT TO NORTHWEST HAS OCCURRED AT BFD AND WILL REACH THE CENTRAL MTNS BETWEEN 13-15Z...AND MDT ARND 18Z. CHANGEOVER TO SNOW WILL FOLLOW THE FROPA BY A COUPLE OF HOURS...MAINLY AS THE PRECIP IS TAPERING OFF DURING THIS AFTN. LLWS WILL ALSO BE A CONCERN ACROSS THE AREA AS CORE OF STRONG WINDS ALOFT MOVES OVR THE STATE THIS MORNING. USING MDL 0-0.5KM BULK SHEAR AS A CUTOFF...SUGGESTS STRONGEST CASE FOR LLWS CRITERIA WILL BE AT BFD...WITH SOMEWHAT WEAKER SHEAR FURTHER SOUTH. SLOW IMPROVEMENT TO AT LEAST MVFR EXPECTED AFTER 00Z SUN NIGHT AS HIGH PRESSURE MOVES INTO THE REGION. OUTLOOK... MON-TUE...NO SIG WX EXPECTED. WED...RAIN OR SNOW POSS LATE...ESP WEST. THU...RAIN POSSIBLE. && .CTP WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH UNTIL 2 PM EST THIS AFTERNOON FOR PAZ005-006- 010>012-017-018-024-033-037-041-042. WINTER WEATHER ADVISORY UNTIL 4 AM EST MONDAY FOR PAZ012-041- 042. WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR PAZ010-011-017-018. FLOOD WATCH THROUGH LATE TONIGHT FOR PAZ036-056>059-063>066. FLOOD WATCH THROUGH THIS EVENING FOR PAZ019-025>028-034-035- 045-046-049>053. WINTER STORM WARNING UNTIL 4 AM EST MONDAY FOR PAZ006-037. WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR PAZ004-005. && SYNOPSIS...DANGELO NEAR TERM...DANGELO SHORT TERM...GARTNER LONG TERM...MARTIN AVIATION...GARTNER
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE STATE COLLEGE PA 513 AM EST SUN MAR 6 2011 PAZ012-041-042-071015- NORTHERN CLINTON-NORTHERN LYCOMING-SULLIVAN- 513 AM EST SUN MAR 6 2011 ...FLOOD WATCH IN EFFECT UNTIL 2 PM EST THIS AFTERNOON... ...WINTER WEATHER ADVISORY IN EFFECT FROM 10 AM THIS MORNING TO 4 AM EST MONDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. FLOOD WATCH. WINTER WEATHER ADVISORY. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. PAZ010-011-017-018-071015- ELK-CAMERON-CLEARFIELD-NORTHERN CENTRE- 513 AM EST SUN MAR 6 2011 ...FLOOD WATCH IN EFFECT UNTIL 2 PM EST THIS AFTERNOON... ...WINTER WEATHER ADVISORY IN EFFECT FROM 10 AM THIS MORNING TO 10 PM EST THIS EVENING... THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. FLOOD WATCH. WINTER WEATHER ADVISORY. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. PAZ036-056>059-063>066-071015- FRANKLIN-PERRY-DAUPHIN-SCHUYLKILL-LEBANON-CUMBERLAND-ADAMS-YORK- LANCASTER- 513 AM EST SUN MAR 6 2011 ...FLOOD WATCH IN EFFECT THROUGH LATE TONIGHT... THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. FLOOD WATCH. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. PAZ019-025>028-034-035-045-046-049>053-071015- SOUTHERN CENTRE-BLAIR-HUNTINGDON-MIFFLIN-JUNIATA-BEDFORD-FULTON- SOUTHERN CLINTON-SOUTHERN LYCOMING-UNION-SNYDER-MONTOUR- NORTHUMBERLAND-COLUMBIA- 513 AM EST SUN MAR 6 2011 ...FLOOD WATCH IN EFFECT THROUGH THIS EVENING... THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. FLOOD WATCH. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. PAZ006-037-071015- POTTER-TIOGA- 513 AM EST SUN MAR 6 2011 ...FLOOD WATCH IN EFFECT UNTIL 2 PM EST THIS AFTERNOON... ...WINTER STORM WARNING IN EFFECT FROM 10 AM THIS MORNING TO 4 AM EST MONDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. FLOOD WATCH. WINTER STORM WARNING. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. PAZ024-033-071015- CAMBRIA-SOMERSET- 513 AM EST SUN MAR 6 2011 ...FLOOD WATCH IN EFFECT UNTIL 2 PM EST THIS AFTERNOON... THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. FLOOD WATCH. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. PAZ005-071015- MCKEAN- 513 AM EST SUN MAR 6 2011 ...WINTER WEATHER ADVISORY IN EFFECT UNTIL 10 PM EST THIS EVENING... ...FLOOD WATCH IN EFFECT UNTIL 2 PM EST THIS AFTERNOON... THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. FLOOD WATCH. WINTER WEATHER ADVISORY. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. PAZ004-071015- WARREN- 513 AM EST SUN MAR 6 2011 ...WINTER WEATHER ADVISORY IN EFFECT UNTIL 10 PM EST THIS EVENING... THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. WINTER WEATHER ADVISORY. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE STATE COLLEGE PA 845 AM EST SUN MAR 6 2011 PAZ017-018-024-025-033-034-061900- CLEARFIELD-NORTHERN CENTRE-CAMBRIA-BLAIR-SOMERSET-BEDFORD- 845 AM EST SUN MAR 6 2011 ...RAIN WILL BE CHANGING TO SNOW DURING THE LATE MORNING AND EARLY AFTERNOON HOURS LEADING TO HAZARDOUS TRAVEL CONDITIONS ACROSS THE HIGHER ELEVATIONS... A SOAKING RAIN WILL MIX WITH SLEET AND SNOW BETWEEN 930 AM AND 1030 AM BEFORE CHANGING ALL SNOW BY NOON ACROSS THE HIGHER ELEVATIONS TO THE WEST OF INTERSTATE 99 AND ROUTE 220. THE SNOW COULD FALL HEAVY AT TIMES THROUGH THE MID AFTERNOON HOURS...BEFORE GRADUALLY DIMINISHING EARLY THIS EVENING. SNOW ACCUMULATIONS OF 2 TO 3 INCHES WILL OCCUR...MAINLY AT ELEVATIONS OVER 1500 FEET ABOVE SEA LEVEL. UP TO 4 INCHES COULD ACCUMULATE ON THE RIDGE TOPS TO THE WEST OF ROUTES 219 AND 220 IN THE LAUREL HIGHLANDS...AND ON THE HIGHER TERRAIN NEAR AND TO THE WEST OF SNOW SHOE ALONG INTERSTATE 80. LESSER AMOUNTS WILL OCCUR IN THE VALLEYS ALONG THE INTERSTATE 99...ROUTE 220 CORRIDOR. TEMPERATURES WILL FALL THROUGH THE 30S LATE THIS MORNING ACROSS THE HIGHER ELEVATIONS WEST OF INTERSTATE 99...AND DIP BELOW FREEZING ACROSS THE HIGHER ELEVATIONS EARLY THIS AFTERNOON. TEMPERATURES IN THE VALLEYS FURTHER EAST WILL GRADUALLY FALL THROUGH THE 40S LATE THIS MORNING...AND INTO THE MID AND UPPER 30S THIS AFTERNOON. VISIBILITY COULD BE ONE HALF MILE OR LESS AT TIMES LATE THIS MORNING THROUGH THE AFTERNOON...WITH ROADS BECOMING SNOW AND SLUSH COVERED. USE CAUTION IF YOU PLAN TO TRAVEL AND ALLOW PLENTY OF EXTRA TIME TO REACH YOUR DESTINATION. LAMBERT
The national radar mosaic for the moment the first event began.
13 heavy snow. Local standard time, as filed.
Snowfall snowfall amounts between 6 and 10 inches were reported mainly over the eastern half of the county.
Snowfall amounts ranged from 12 to 14 inches.
Snowfall amounts ranged from 10 to 12 inches.
Snowfall amounts ranged from 10 to 12 inches.
Snowfall amounts ranged from 12 to 14 inches.
Snowfall amounts ranged from 8 to 10 inches.
Snowfall amounts ranged from 8 to 10 inches.
Snowfall amounts ranged from 8 to 10 inches.
Snowfall amounts ranged from 9 to 11 inches.
Snowfall amounts ranged from 7 to 10 inches.
Snowfall amounts ranged from 7 to 10 inches.
Snowfall amounts ranged from 7 to 10 inches.
Snowfall amounts ranged from 7 to 10 inches.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2011Every state in 2011This day in weather historyWarnings in Pennsylvania, March 2011
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: 277572, 277579, 277573, 277577, 277580, 277575, 277574, 277576, 277578, 277581, 277582, 277583, 277584.