A seasonably cold westerly flow over the record-warm waters of Lake Erie produced localized lake-effect snowfall accumulation between 6 and 8 inches over far northwest Warren County. The heaviest snow bands with snowfall rates of 1 inch per hour impacted the favored lake-effect snowbelt in northwest Pennsylvania during the early morning hours.
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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 seasonably cold westerly flow over the record-warm waters of Lake Erie produced localized lake-effect snowfall accumulation between 6 and 8 inches over far northwest Warren County. The heaviest snow bands with snowfall rates of 1 inch per hour impacted the favored lake-effect snowbelt in northwest Pennsylvania during the early morning hours.
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 18, 6:29 PM EST, 31 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 629 PM EST FRI DEC 18 2015 .SYNOPSIS... A DEEP BUT FAST MOVING UPPER TROUGH IS MOVING THROUGH THE REGION BRINGING A TOUCH OF WINTER. AN UPPER RIDGE WILL MOVE OVER THE AREA SUNDAY AND THE START OF THE NEW WEEK...RESULTING IN A REBOUND IN TEMPERATURES WHICH WILL LAST AT LEAST THROUGH MID WEEK. && .NEAR TERM /THROUGH SATURDAY/... THE SECONDARY COLD FRONT IS ENTERING WESTERN PA ACCOMPANIED BY AN AREA OF LIGHT SNOW. THE MAIN EFFECT WILL BE TO TURN THE WIND MORE OFF THE GR LAKES AND HELP DEVELOP BANDED LAKE EFFECT SNOW SHOWERS...WHICH THE HRRR SHOWS BEGINNING TO EVOLVE BETWEEN ABOUT 10PM AND MIDNIGHT. MADE ONLY MINOR TWEAKS TO THE NEAR TERM AS IT LOOKS LIKE A MORE OR LESS TYPICAL LAKE EFFECT EVENT WITH THE BEST CHANCE FOR MEASURABLE SNOW BEING OVER MY NWRN ZONES AND SOME UPSLOPE AREAS OF THE LAURELS. *SIGNIFICANT LAKE EFFECT SNOW ACROSS THE NORTHWEST PA SNOWBELT TONIGHT INTO SATURDAY* THE 3KM HRRR INITIALLY IT KEEPS THE MAIN BAND NORTH OF THE PA/NY BORDER. IT DOES SHOW SOME MEASURABLE SNOW BETWEEN ABOUT 10 PM AND 2AM. THE HRRR HAS AN INTENSE BAND OF HEAVY SNOW AT THIS TIME IN NY STATE...THIS BAND HAS 0.50 TO 0.70 INCHES OF QPF...THAT IS A LOT OF LES POTENTIAL. BASED ON THE HRRR...PREVIOUS NCAR EFS KEPT OUR SNOW IN THE 5-8" RANGE IN EXTREME NORTHERN WARREN COUNTY AND LOWER TO SOUTH AND EAST. ALSO SHOWED SOME SNOW IN THE LAURELS. MOST OTHER AREAS COULD SEE SOME SNOW FLURRIES OVERNIGHT AND EARLY SATURDAY. IT WILL BECOME QUITE BREEZY SATURDAY IN THE COLD AIR. SOME GUIDANCE SHOWS CLOSE TO ADVISORY CATEGORY GUSTS IN THE SOUTHWEST MOUNTAINS SATURDAY AFTERNOON. PREVIOUS INFORMATION ON NCAR ENSEMBLE FORECAST... THE NCAR 3KM ENSEMBLE SHOWS THAT THE FIRST INCH OF SNOW AT THE 90 PERCENT CONFIDENCE LEVEL FALLS IN NORTHERN WARREN COUNTY BY LATE EVENING. THE 3 INCH VALUES ARE REACHED BY ABOUT 8 AM SATURDAY. THE 6 INCH PROBABILITY AT 80 PERCENT OUR GREATER MOVES IN AROUND 10 AM AND PEAKING NEAR 100 PERCENT BY 3-4 PM. BEST CHANCE ACROSS NORTHERN AREAS OF WARREN COUNTY. THERE IS A 10 PERCENT CHANCE OF 1 FOOT OF SNOW IN A SLIVER OF NORTHWESTERN WARREN COUNTY. VERY LOW CHANCE OF A FOOT IN THE 3KM MODELS. && .SHORT TERM /SATURDAY NIGHT/... HIGH PRESSURE WILL BUILD IN AND BRING ABOUT A LOWERING INVERSION HEIGHT AND GRADUALLY BACKING WINDS...WHICH SHOULD SHUT OFF THE BEST OF THE LAKE EFFECT SNOW SHOWERS. SHOULD BE THE COLDEST NIGHT WE HAVE HAD FOR A WHILE...IN THE LOW TO MID 20S...WHICH WILL ONLY BE A DEGREE OR 2 EITHER SIDE OF NORMAL. && .LONG TERM /SUNDAY THROUGH FRIDAY/... A RIDGE OF HIGH PRESSURE AT THE SURFACE AND ALOFT WILL DRIFT EAST ACROSS THE COMMONWEALTH ON SUNDAY...ACCOMPANIED BY A SLIGHT MODERATION IN TEMPERATURES AND LIGHTER WINDS. TEMPERATURES WILL CONTINUE TO REBOUND ON MONDAY...AS WARM AIR FROM THE SOUTH FILTERS INTO THE REGION AHEAD OF A COLD FRONT. THE COLD FRONT WILL PUSH ACROSS THE STATE LATE MONDAY INTO TUESDAY...BRINGING SCATTERED SHOWERS. MODELS STILL HAVE SOME TIMING VARIATIONS...BUT RAINFALL SHOULD BE LIMITED AND MOST LOCATIONS WILL SEE NO MORE THAN A FEW TENTHS OF AN INCH. A MOIST SOUTHERLY FLOW WILL CONTINUE ACROSS THE AREA TUESDAY...BRINGING MILD TEMPERATURES AND A CONTINUED CHANCE FOR SOME LIGHT SHOWERS. ANOTHER FRONT WILL SWEEP ACROSS THE STATE WEDNESDAY INTO THURSDAY...RESULTING IN A FAIRLY HEALTHY RAIN EVENT. 18DEC 12Z GEFS/EC BLEND CONTINUES TO INDICATE THE POTENTIAL FOR OVER ONE INCH OF RAIN IN SOME LOCATIONS OF THE STATE. ITS STILL MUCH TOO EARLY TO PIN DOWN ANY TYPE OF MESOSCALE FOCUS THAT WOULD LEAD TO HEAVIER RAIN BANDS. AT THIS POINT...CHRISTMAS EVE LOOKS TO BE THE WARMEST DAY NEXT WEEK WITH TEMPERATURES NUDGING INTO THE 60S IN THE SOUTHEAST. HOWEVER...A LOT DEPENDS ON THE TIMING OF THE FRONTAL PASSAGE AND ENSEMBLE SOLUTIONS STILL INDICATE A GOOD DEAL OF TEMPERATURE SPREAD. && .AVIATION /23Z FRIDAY THROUGH WEDNESDAY/... UPDATE THE TAFS MOST SITES ARE NOW SHOWING THE SURGE OF THE SECONDARY COLD PUSH WITH SOME GUSTY WINDS OVER THE REGION AND SPREADING EASTWARD. WINDS ACTUALLY SHOULD PEAK SATURDAY. MOST AREAS TO THE EAST ARE VFR WITH MORE MVFR TO THE WEST AND NORTHWEST. WINDS AND LOW CLOUDS WILL BE THE ISSUE FOR THE REST OF TODAY. SIGNIFICANT SNOW SHOWERS STILL HAVE NOT DEVELOPED. THIS WILL CHANGE IN THE 5-8 PM TIME FRAME IN THE NORTHWEST WHERE LAKE EFFECT SNOW WILL LOWER CIGS/VSBY AND SOME AREAS OF THE LAURELS. THE BEST SNOW WILL BE IN THE NORTHERN AREAS OF WARREN COUNTY OVERNIGHT AND INTO SATURDAY...AFFECTING KBFD. PUT SOME MENTION SNOW AT KJST TOO. MOST OTHER AREAS SHOULD BE QUITE GOOD OVERNIGHT AND SATURDAY...EXCEPT FOR GUSTY WINDS ESPECIALLY SATURDAY. SNOW TAPERS OFF IN NW SATURDAY EVENING/OVERNIGHT. AND THINGS IMPROVE...SUNDAY BIG BUBBLE NO TROUBLE AND VFR SHOULD DOMINATE. OUTLOOK... MON...PM SHRA/LOW CIGS POSS NW. TUE...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... LAKE EFFECT SNOW ADVISORY UNTIL 10 PM EST SATURDAY FOR PAZ005. LAKE EFFECT SNOW WARNING UNTIL 10 PM EST SATURDAY FOR PAZ004. && SYNOPSIS...GRUMM/LA CORTE NEAR TERM...GRUMM/LA CORTE SHORT TERM...GRUMM/LA CORTE LONG TERM...HAGNER AVIATION...GRUMM
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE STATE COLLEGE PA 341 AM EST FRI DEC 18 2015 PAZ006-010>012-017>019-024>028-033>037-041-042-045-046-049>053- 056>059-063>066-190845- POTTER-ELK-CAMERON-NORTHERN CLINTON-CLEARFIELD-NORTHERN CENTRE- SOUTHERN CENTRE-CAMBRIA-BLAIR-HUNTINGDON-MIFFLIN-JUNIATA-SOMERSET- BEDFORD-FULTON-FRANKLIN-TIOGA-NORTHERN LYCOMING-SULLIVAN- SOUTHERN CLINTON-SOUTHERN LYCOMING-UNION-SNYDER-MONTOUR- NORTHUMBERLAND-COLUMBIA-PERRY-DAUPHIN-SCHUYLKILL-LEBANON-CUMBERLAND- ADAMS-YORK-LANCASTER- 341 AM EST FRI DEC 18 2015 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...SATURDAY THROUGH THURSDAY. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. PAZ005-190845- MCKEAN- 341 AM EST FRI DEC 18 2015 ...LAKE EFFECT SNOW ADVISORY IN EFFECT FROM 7 PM THIS EVENING TO 10 PM EST SATURDAY... 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 ADVISORY. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY. 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 ADVISORY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. PAZ004-190845- WARREN- 341 AM EST FRI DEC 18 2015 ...LAKE EFFECT SNOW WARNING IN EFFECT FROM 7 PM THIS EVENING TO 10 PM EST SATURDAY... 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...SATURDAY THROUGH THURSDAY. 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.
The national radar mosaic for the moment the first event began.
1 lake-effect snow. Local standard time, as filed.
COOP Observers in Bear Lake and Chandlers Valley reported 6 to 7 inches of snow accumulation.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2015Every state in 2015This day in weather historyWarnings in Pennsylvania, December 2015
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: 605047.