A cold and persistent northwest flow across the Eastern Great Lakes resulted in a prolonged period of lake effect and orographically-enhanced snow showers over the Northwest Mountains and Laurel Highlands. The most significant snow accumulations were localized with the highest amounts between 8 and 12 inches.
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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 CTP wrote it up.
A cold and persistent northwest flow across the Eastern Great Lakes resulted in a prolonged period of lake effect and orographically-enhanced snow showers over the Northwest Mountains and Laurel Highlands. The most significant snow accumulations were localized with the highest amounts between 8 and 12 inches. Frequent wind gusts between 25 and 35 mph produced areas of blowing snow and near-blizzard conditions at times. Temperatures in the single digits and teens combined with brisk winds produced wind chills as cold at 10 below zero.
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 Dec 13, 4:45 AM EST, 2 hours 15 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 445 AM EST MON DEC 13 2010 .SYNOPSIS... AN UPPER LEVEL LOW WILL REMAIN PARKED OVER NEW ENGLAND THIS WEEK...FUNNELING A COLD NORTHWEST FLOW ACROSS PENNSYLVANIA WITH LAKE EFFECT SNOW SHOWERS ACROSS THE WESTERN MTNS. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... REGIONAL RADAR LOOP SHOWING LAKE TWO AREAS OF PRECIP AFFECTING CENTRAL PA. LG SCALE FORCING AHEAD OF UPPER TROF PRODUCING -SN ACROSS THE SUSQ VALLEY. TO THE WEST...LAKE EFFECT SNOW COMMENCING AS BLYR FLOW VEERS TO THE NW. LATEST MDL DATA SUGGESTS PATCHY -SN WILL TAPER OFF OVR THE SUSQ VALLEY BY MIDDAY...AS TROF SHIFTS EAST. LATEST RADAR TRENDS AND MDL SUGGEST NO MORE THAN A DUSTING ACROSS THE E ZONES. MEANWHILE...MAIN STORY WILL BECOME LOCALLY HVY LAKE EFFECT SNOWS ACROSS THE LAURELS AND NW MTNS. WELL ALIGNED NW FLOW WITH LITTLE SHEAR AND PLENTY OF COLD AIR FLOWING OVR THE UNFROZEN LAKES WILL PRODUCE PERSISTENT SHSN ALONG THE SPINE OF THE ALLEGHENIES. MDL DATA CONTS TO INDICATE THE LAUREL HIGHLANDS WILL BE THE TARGET FOR THE STEADIEST/HEAVIEST SNOW...GIVEN A FAVORABLE NNW FLOW AND LK HURON CONNECTION. TYPICAL LAKE EFFECT SNOW/LIQUID RATIOS OF ARND 20/1 HAVE BEEN USED AND SUPPORT ACCUMS OF 2-5 INCHES ACROSS SOMERSET CO BY THIS EVENING. THE SNOW WILL BE WHIPPED ARND BY A GUSTY NW WIND...CREATING NR BLIZZARD CONDS ACROSS THE LAURELS BY LATER TDY. BUFKIT DATA SUPPORTS FREQUENT GUSTS BTWN 30-35KTS BY AFTN OVR SOMERSET/CAMBRIA COUNTIES. THE SNOWBELT OF NW WARREN COUNTY ALSO APPEARS LIKELY TO RECEIVE CLOSE TO 5 INCHES BY EVENING. TEMPS IN THE TEENS...COMBINED WITH THE GUSTY WINDS...WILL CREATE WIND CHILLS NR ZERO ACROSS THE W MTNS BY LATE TODAY. DRYING/DOWNSLOPING FLOW EAST OF THE MTNS WILL RESULT IN ONLY SCT -SHSN TODAY AND LITTLE IF ANY ACCUM. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... NNW BLYR FLOW WILL CONTINUE TO TRAIN FOCUS OF LAKE EFFECT MOISTURE INTO THE LAUREL HIGHLANDS TONIGHT AND EARLY TUES. GRADUALLY BACKING BLYR FLOW LATE TUES SHOULD SHIFT THE FOCUS OF LAKE EFFECT BANDS NORTHWARD...TARGETING WARREN CO SE INTO THE CENTRAL MTNS BY TUE EVENING. SEVERAL INCHES OF ADDITIONAL ACCUM EXPECTED BOTH TONIGHT AND TUES ACROSS THE LAURELS AND NW MTNS. LATER SHIFTS MAY SERIOUSLY NEED TO CONSIDER UPGRADING TO BLIZZARD WARNINGS...AS TIGHT PRES GRAD WILL CONTINUE TO CREATE STRONG/GUSTY WINDS AND CONSIDERABLE BLOWING/DRIFTING. BUFKIT SOUNDING DATA CONTINUES TO INDICATE FREQUENT GUSTS ARND 35KTS ACROSS THE ALLEGHENY MTNS TONIGHT AND TUES. CORE OF THE COLDEST AIR IS PROGGED TO PASS OVR PA TONIGHT AND TUES...WHEN GEFS MEAN 850 TEMPS BOTTOM OUT NR -18C. THE COLD AIR...COMBINED WITH GUSTY WINDS...WILL LIKELY RESULT IN WIND CHILLS NR -10F ACROSS THE W MTNS TONIGHT AND ACTUAL HIGHS TUES ONLY IN THE TEENS. EVEN ACROSS THE SUSQ VALLEY...WIND CHILLS BTWN ZERO AND 10 ABV EXPECTED TONIGHT AND TUES. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... GENERAL AGREEMENT AMONG MED RANGE GUIDANCE THRU WED...ALL SHIFTING UPPER LOW NE INTO NEW ENG. THE RESULTING BACKING BLYR FLOW WILL CAUSE FOCUS OF LAKE EFFECT BANDS TO SHIFT INTO NORTHERN PA. ONLY A SLIGHT MODERATION IN TEMPS/WINDS EXPECTED MIDWEEK. ENS MEAN 850 TEMPS NR -14C WED SHOULD TRANSLATE TO HIGHS IN THE 20S TO L30S. MED RANGE MDLS BEGIN TO DIVERGE WITH RESPECT TO TRACK OF CLIPPER SYSTEM LATE THIS WEEK. HOWEVER...SOUTHERN PA STANDS THE BEST CHC FOR A PERIOD OF LGT SNOW AS THIS SYSTEM PASSES S OF THE STATE THURSDAY. OVERALL PATTERN OF NEG NAO AND UPPER LOW LOCKED IN OVR NEW ENG FAVORS BLW NORMAL TEMPS THRU NEXT WEEKEND. ALTHOUGH ENS MEAN 850 TEMPS INDICATE FRI-SUN WILL BE NOT NEARLY AS COLD AS THE NEXT COUPLE OF DAYS. ODDS SEEM TO FAVOR GENERALLY DRY WX INTO THE WEEKEND. HOWEVER...SEVERAL GEFS MEMBERS INDICATE AT LEAST THE POTENTIAL FOR A WIDESPREAD SNOWFALL ARND NEXT SUNDAY WITH CLIPPER AND POSS COASTAL REDEVELOPMENT. && .AVIATION /09Z MONDAY THROUGH FRIDAY/... COLDER AIR MOVING IN FROM THE WEST WILL REINFORCE THE IFR CONDITIONS ACROSS THE HIGHER ELEVATIONS...WHILE DOWNSLOPE FLOW WILL KEEP CENTRAL MTNS MVFR AND SUSQ VALLEY VFR. SNOW SHOWERS/SQUALLS WILL RETURN TO THE HIGHER ELEVATIONS ON MONDAY IN TYPICAL NW FLOW LAKE- ENHANCED UPSLOPE REGIME. NW FLOW ALSO INCREASES MON AFTERNOON WITH 850 MB FLOW INCREASING TO AROUND 50 KTS...WHICH WILL LEAD TO LLWS CONDITIONS AS WELL AS STRONGER AND GUSTY WINDS AT THE SURFACE. OUTLOOK... MON-WED...NW FLOW BRINGS FREQ SHSN/LOW CIGS TO MAINLY NORTHERN AND WESTERN MTNS. THU/FRI...MVFR AND VFR AS HIGH PRESSURE BUILDS. && .CTP WATCHES/WARNINGS/ADVISORIES... LAKE EFFECT SNOW WARNING FROM 7 AM THIS MORNING TO 7 AM EST WEDNESDAY FOR PAZ004-005. WINTER STORM WARNING FROM 7 AM THIS MORNING TO 7 PM EST TUESDAY FOR PAZ024-033. && SYNOPSIS...FITZGERALD NEAR TERM...FITZGERALD SHORT TERM...FITZGERALD LONG TERM...FITZGERALD/MARTIN AVIATION...CERU/RXR
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE STATE COLLEGE PA 531 AM EST MON DEC 13 2010 PAZ006-010>012-017>019-025>028-034>037-041-042-045-046-049>053- 056>059-063>066-141045- POTTER-ELK-CAMERON-NORTHERN CLINTON-CLEARFIELD-NORTHERN CENTRE- SOUTHERN CENTRE-BLAIR-HUNTINGDON-MIFFLIN-JUNIATA-BEDFORD-FULTON- FRANKLIN-TIOGA-NORTHERN LYCOMING-SULLIVAN-SOUTHERN CLINTON- SOUTHERN LYCOMING-UNION-SNYDER-MONTOUR-NORTHUMBERLAND-COLUMBIA-PERRY- DAUPHIN-SCHUYLKILL-LEBANON-CUMBERLAND-ADAMS-YORK-LANCASTER- 531 AM EST MON DEC 13 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. PAZ004-005-141045- WARREN-MCKEAN- 531 AM EST MON DEC 13 2010 ...LAKE EFFECT SNOW WARNING IN EFFECT UNTIL 7 AM EST WEDNESDAY... 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. LAKE EFFECT SNOW WARNING. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. LAKE EFFECT SNOW WARNING. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. PAZ024-033-141045- CAMBRIA-SOMERSET- 531 AM EST MON DEC 13 2010 ...WINTER STORM WARNING IN EFFECT UNTIL 7 PM EST TUESDAY... 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 STORM WARNING. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. WINTER STORM WARNING. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.
The national radar mosaic for the moment the first event began.
2 lake-effect snow, 2 heavy snow. Local standard time, as filed.
Localized lake-effect snowfall amounts ranged between 8 and 12 inches.
Localized lake-effect snowfall amounts ranged between 8 and 12 inches.
Localized upslope snowfall amounts ranged between 3 and 6 inches, with up to 8 inches on the ridgetops. Blustery wind gusts over 30 mph combined with very cold temperatures in the single digits to low teens to produce dangerous near-blizzard conditions with 1/4 mile or less visibility and sub-zero wind chills.
Localized upslope snowfall amounts ranged between 3 and 6 inches, with up to 8 inches on the ridgetops. Blustery wind gusts over 30 mph combined with very cold temperatures in the single digits to low teens to produce dangerous near-blizzard conditions with 1/4 mile or less visibility and sub-zero wind chills.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2010Every state in 2010This day in weather historyWarnings in Pennsylvania, December 2010
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: 264974, 264975, 264977, 264978.