A narrow convective line, void of lightning, moved rapidly eastward through central PA during the early morning hours. The line was along the leading edge of a surface wind shift and in an environment characterized by very strong low level wind fields and minimal to no instability.
Every event with a place to put it. 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.
A narrow convective line, void of lightning, moved rapidly eastward through central PA during the early morning hours. The line was along the leading edge of a surface wind shift and in an environment characterized by very strong low level wind fields and minimal to no instability. Isolated strong to locally severe wind gusts occurred along the line, with damage reported in Somerset and Elk counties.
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 22, 2:15 AM EST, 1 hour 40 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 215 AM EST SUN DEC 22 2013 .SYNOPSIS... AN UNSEASONABLY MILD AND FAST SOUTHWEST FLOW WILL PRECEDE A COLD FRONT PUSHING SLOWLY EASTWARD FROM THE UPPER OHIO VALLEY. IT WILL FEEL LIKE SPRING TODAY AS TEMPERATURES SURGE TO NEAR RECORD LEVELS IN ADVANCE OF THE FRONT. A SECONDARY LOW PRESSURE SYSTEM WILL DEVELOP ALONG FRONT OVER THE SOUTHERN MID-ATLANTIC PIEDMONT AND TRACK NORTHEAST NEAR THE MID-ATLANTIC COAST LATE TONIGHT INTO EARLY MONDAY. NOTICEABLY COLDER AIR WILL RETURN TO THE AREA BY CHRISTMAS EVE WITH GUSTY WINDS AND LAKE EFFECT SNOWS. AFTER A COLD START FOR CHRISTMAS MORNING...CONDITIONS SHOULD IMPROVE...BUT IT WILL STAY QUITE COLD FOR CHRISTMAS DAY WITH THE ARRIVAL OF HIGH PRESSURE. && .NEAR TERM /UNTIL 8 AM THIS MORNING/... VERY ANOMALOUS...WARM AIRMASS BLANKETED MUCH OF THE CWA ATTM...AND SOUTHWESTERLY DEEP LAYER SHEAR WAS OFF THE CHARTS...ESP ACROSS THE NWRN HALF OF THE STATE WHERE 0-6 KM BULK SHEAR WAS OVER 85 KTS...AND EVEN THE BULK SHEAR FROM 0-3 KM WAS AROUND 75 KTS. SOMEWHAT LOWER SHEAR WAS LOCATED ACROSS THE FAR SERN ZONES. A NARROW RIBBON OF HEAVY SHOWERS AND A FEW LOW-TOPPED TSRA WAS APPROACHING THE OHIO/PA BORDER ATTM...AND SPC RECENTLY ISSUED SVR TSRA WATCH 589 RIGHT UP TO THE WESTERN BORDER OF OUR CWA WHERE SOME POCKETS OF LOW MIXED LAYER CAPE WERE PRESENT. AREAS OF SHOWERS WILL CONTINUE TO RACE NE ACROSS THE REGION EARLY THIS MORNING...WITH THE BULK OF THE RAIN FALLING OVER THE NW 1/2 OT 2/3RDS OF THE STATE...WHERE ANOTHER ONE-HALF...TO THREE QUARTERS OF AN INCH IS LIKELY BY 12Z. A VERY SHARP QUASI STNRY BOUNDARY WILL BE STRETCHED EAST TO WEST JUST NORTH OF THE PA/NY BORDER THROUGH THE MID MORNING. THIS FRONT WILL GRADUALLY RETREAT NWD AS A PAIR OF SFC LOWS /FROM NERN OHIO...TO SRN INDIANA/ MOVE NORTHEAST. COOLEST TEMPS EARLY TODAY WILL CONTINUE TO BE FOUND ACROSS THE MIDDLE SUSQ VALLEY...AND NCENT MTNS. ELSEWHERE...TEMPS IN THE UPPER 50S TO UPPER 60S WILL BE 25-30 DEG F ABOVE THEIR NORMAL AFTERNOON HIGH TEMPS FOR LATE DEC. SO FAR THE ONLY FLOOD WARNING IS ON CONEWANGO CREEK AT RUSSELL IN WARREN COUNTY. FORTUNATELY WATER LEVELS ARE LOW GOING INTO THIS EVENT AND THAT SHOULD HELP MINIMIZE FLOODING. ALSO...THE VERY WARM AND MOIST AIR PASSING OVER THE COOL GROUND WILL LEAD TO PATCHY FOG...WITH VSBYS AT PRIMARY ASOS SITES LIKELY STAYING MAINLY ABOVE 2SM. && .SHORT TERM /8 AM THIS MORNING THROUGH 6 PM MONDAY/... INITIAL FRONTAL BOUNDARY MARCHES EAST ACROSS PENN DURING THE DAY SUNDAY AS THE STRONG SWRLY LLJ IN EXCESS OF 40KTS SHIFTS EAST TO THE SUSQ RIVER VALLEY BY 21Z. THE STEADIER RAIN WILL HAVE ENDED ACROSS THE WESTERN HALF OF PENN BY 21Z...WITH PW DROPPING LIKE A STONE FROM WEST TO EAST DURING THE AFTERNOON/EARLY EVENING HOURS SUNDAY AFTERNOON. THE BEST COMBINATION OF LLVL MOISTURE...SHEAR AND WARMTH WILL RESIDE OVER THE SUSQ VALLEY AND POINTS EAST ON SUNDAY. THIS IS WHERE SEVERAL VERSION OF U.S. AND INTN/L OPERATIONAL MODEL GUIDANCE INDICATES THE CHC FOR SOME LOW-TOPPED TSRA...ESPECIALLY IS SOME FLEETING BREAKS OF SUNSHINE POKE THEIR WAY THROUGH THE OTHERWISE ANTICIPATED MULTI-LAYERED CLOUD DECK. THE GEFS ACTUALLY TRIES TO DEVELOP 100-300J OF CAPE ACROSS SERN PA AND NJ DURING THE DAY SUNDAY. ANY NEAR SFC-BASED CAPE IN DECEMBER IS QUITE RARE IN THIS PART OF THE COUNTRY...SO WILL CONTINUE TO MENTION THE CHC OF THUNDERSTORMS IN SE COUNTIES SUNDAY AFTERNOON. TEMPERATURES SUNDAY...BOTH AT THE SURFACE AND 850 MB...ROCKET INTO +2 TO +3 SD RANGE. TEMPERATURES AT *850 MB* WILL APPROACH THE RECORD *SURFACE* HIGHS FOR THE DATE. WE CONTINUE TO EXPECT +25F TO +30F DEPARTURES FROM NORMAL OVER SOUTHEAST PA...WITH HIGHS IN THE U50S ACROSS THE NORTH AND LOWER TO MID 60S ACROSS MUCH OF THE CENTRAL AND SOUTH. 850 HPA TEMPS BETWEEN 7 AND MIDNIGHT SUNDAY IN NW DROP BACK BELOW 0C...SO WE/LL MAINTAIN THE MENTION OF SNOW SHOWERS IN NW PA OVERNIGHT SUNDAY INTO MONDAY. THE COLD AIR WILL TAKE UNTIL MONDAY EVENING TO GET THROUGH OUR ENTIRE COUNTY WARNING AREA. AS THE ASSOCIATED COLD FRONT SWEEPS THROUGH THE STATE SUNDAY NIGHT...TEMPERATURES WILL DROP OFF STEADILY IN THE WESTERLY FLOW. THE LATEST SREF PLACES A SHARP E/W GRADIENT IN THE PROB OF 850 MB TEMPS BELOW ZERO - RIGHT OVER WARREN COUNTY. HOWEVER...THE 00Z EC AND GFS APPEARS AT LEAST SEVERAL HOURS QUICKER THAN THE NAM/SREF TANDEM. ELSEWHERE...LOWS THROUGHOUT THE CENTRAL RIDGE AND VALLEY REGION OF THE STATE WILL RANGE FROM THE MID 40S...AND IN THE U40S TO AROUND 50 IN THE SE. SOME LAKE EFFECT SNOWS ARE POSSIBLE ACROSS THE FAR NORTHERN PARTS OF WARREN COUNTY TWD DAYBREAK MONDAY MORNING ON A WESTERLY TRAJECTORY WITH LOW TEMPS IN THE 32-35F RANGE. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... UPPER TROFFING WILL REMAIN DOMINANT OVER THE EASTERN THIRD OF THE COUNTRY THROUGH MID WEEK. A SECONDARY SHORTWAVE WILL KEEP PRECIPITATION OVER THE STATE THROUGH MONDAY...MAINLY IN THE FORM OF RAIN. DRY AND NOTICEABLY COLDER WEATHER WILL THEN DOMINATE THROUGH MUCH OF THE REMAINDER OF THE LONG TERM PERIOD. THE CORE OF THE COLDEST AIR THIS WEEK WILL MOVE THROUGH TUESDAY AFTERNOON WITH GEFS AVERAGE 850 MB TEMPS IN THE -16C RANGE COMING ACROSS LAKES HURON AND ERIE. THE 00Z EC SHOWS THE TROUGH AXIS CROSSING WESTERN LAKE ERIE AND THE OHIO VALLEY AT 12Z MONDAY. THE DEEP COLD AIR AND MDTLY STRONG MEAN WESTERLY BOUNDARY LAYER FLOW TUESDAY SHOULD LEAD TO SOME DECENT LAKE EFFECT SNOW SHOWERS BANDS PENETRATING WELL INLAND AND PERHAPS BRINGING EVEN A LIGHT COATING TO PORTIONS OF THE CENTRAL RIDGE AND VALLEY REGION. THE NW ZONES AND LAURELS WILL SEE A LIKELIHOOD OF SNOW SHOWERS WITH 1 TO 3 INCHES OF ACCUM. THIS UPPER TROUGH...COMBINED WITH A FETCH ACROSS THE LAKES...MAY GIVE SOME HOPE FOR A LIGHT COATING OF SNOW TUESDAY AFTERNOON INTO EARLY CHRISTMAS MORNING OVER CENTRAL PA. AFTER THE PASSAGE OF THIS FEATURE...THE MID WEEK WILL BE HIGHLIGHTED BY A WESTERLY UPPER FLOW COMPONENT WITH SLIGHTLY RISING TEMPERATURES. A WEAK SYSTEM MAY PASS JUST NORTH OF THE AREA ON WEDNESDAY. THERE IS SOME INDICATION OF AN ENSEMBLE MEAN WEAKNESS IN SURFACE PRESSURES ON FRIDAY...BUT NOTHING ORGANIZED AT THIS POINT. && .AVIATION /07Z SUNDAY THROUGH THURSDAY/... A VARIABLE AND ACTIVE AVN PERIOD WILL EVOLVE THROUGH THE FIRST HALF OF THE PERIOD...AS A DYNAMIC SFC LOW TRACKS NEWD FM THE UPPER OH VLY ACRS WRN NY...WITH A TRAILING COLD FRONT PUSHING SLOWLY EWD ACRS THE AIRSPACE. ONLY TROUBLE SPOT CURRENTLY IS BFD WITH IFR CIGS ALTHO THE GUIDANCE WANTS TO TAKE THE SERN TERMINALS DOWN LATER THIS MORNING. CONFIDENCE IS LOW AT MDT/LNS AND TRIED TO PLAY A MIDDLE GROUND BTWN THE GUIDANCE AND CURRENT OBSERVATIONAL TRENDS. WILL BE MONITORING THE EWD PROGRESS OF CONVECTIVELY ENHANCED THIN LINE APPROACHING THE PA/OH BORDER...WHICH AS BEEN PRODUCING SVR WND GUSTS IN ERN OH. THE OTHER SIGNIFICANT AVN IMPACT WILL BE LLWS WITH REGIONAL VWP/S SHOWING 50KT WSW WINDS JUST A FEW THOUSAND FEET AGL. ANTICIPATE SEVERAL UPDATES/AMENDMENTS THROUGH THE MORNING. OUTLOOK... MON...RAIN SE ALONG STALLED FRONTAL ZONE. TUE...LGT SN PSBL WITH STG UPPER LVL TROUGH. GUSTY WNW WINDS. WED...BCMG VFR WITH FAIR CONDS PROVIDED BY SFC HIGH PRES. THU...FEW SNOW SHOWERS POSSIBLE WITH COLD FRONT. && .HYDROLOGY... THE COMBINATION OF MODERATE TO HEAVY RAIN COMBINED WITH SNOW-MELT WILL CONTRIBUTE TO THE POTENTIAL FOR SIGNIFICANT FLOODING ACROSS NRN PA...WITH AN EFFECTIVE 3 INCH+ RAINFALL/SNOWMELT/RUNOFF EXPECTED BY SUNDAY. A FLOOD WATCH IS IN EFFECT FOR FROM WARREN EAST TO TIOGA COUNTY THROUGH MUCH OF TODAY. FLOOD WARNING CONTINUES FOR RUSSELL...WHERE THE RIVER SHOULD CROSS FLOOD STAGE SUNDAY MORNING AND CREST JUST BELOW THE 10 FOOT MODERATE FLOOD LEVEL. SIGNIFICANT RISES AREA EXPECTED ACROSS MOST RIVERS AND STREAMS IN THE WESTERN HALF OF THE FORECAST AREA. && .CTP WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH THROUGH THIS AFTERNOON FOR PAZ004>006-010-011-037. && SYNOPSIS...LAMBERT/STEINBUGL NEAR TERM...LAMBERT SHORT TERM...LAMBERT LONG TERM...LAMBERT/GARTNER AVIATION...STEINBUGL HYDROLOGY...ROSS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE STATE COLLEGE PA 934 PM EST SAT DEC 21 2013 PAZ012-017>019-024>028-033>036-041-042-045-046-049>053-056>059- 063>066-230245- NORTHERN CLINTON-CLEARFIELD-NORTHERN CENTRE-SOUTHERN CENTRE-CAMBRIA- BLAIR-HUNTINGDON-MIFFLIN-JUNIATA-SOMERSET-BEDFORD-FULTON-FRANKLIN- NORTHERN LYCOMING-SULLIVAN-SOUTHERN CLINTON-SOUTHERN LYCOMING-UNION- SNYDER-MONTOUR-NORTHUMBERLAND-COLUMBIA-PERRY-DAUPHIN-SCHUYLKILL- LEBANON-CUMBERLAND-ADAMS-YORK-LANCASTER- 934 PM EST SAT DEC 21 2013 THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...TONIGHT. THE PROBABILITY OF WIDESPREAD HAZARDOUS WEATHER IS LOW. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY. ISOLATED THUNDERSTORMS MAY TRIGGER STRONG WIND GUSTS...MAINLY ACROSS SOUTHERN PENNSYLVANIA AND THE SUSQUEHANNA RIVER VALLEY ON SUNDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. PAZ004>006-010-011-037-230245- WARREN-MCKEAN-POTTER-ELK-CAMERON-TIOGA- 934 PM EST SAT DEC 21 2013 ...FLOOD WATCH IN EFFECT THROUGH SUNDAY AFTERNOON... THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL PENNSYLVANIA. .DAY ONE...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...SUNDAY THROUGH FRIDAY. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV/STATECOLLEGE ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. FLOOD WATCH. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
255 AM EST SUN DEC 22 2013
PAZ005-010-220900-
ELK PA-MCKEAN PA-
255 AM EST SUN DEC 22 2013
...A LINE OF SHOWERS WITH STRONG WIND GUSTS WILL AFFECT SOUTHERN
MCKEAN AND WESTERN ELK COUNTIES...
AT 254 AM EST...SHOWERS WITH STRONG WIND GUSTS WERE LOCATED FROM
TIONESTA TO 36 MILES WEST OF FREEPORT...MOVING EAST AT 50 MPH.
WIND GUSTS TO 50 MPH ARE POSSIBLE WITH THIS LINE OF SHOWERS. THESE
SHOWERS WILL AFFECT JAMES CITY...WILCOX AND BRANDY CAMP.
THIS WILL IMPACT THE FOLLOWING MAJOR ROADS...ROUTE 6...ROUTE 219...
STATE ROAD 66...STATE ROAD 120...STATE ROAD 255.
LAT...LON 4174 7826 4162 7838 4162 7842 4158 7842
4126 7874 4137 7897 4135 7902 4134 7910
4142 7910 4143 7907 4145 7907 4145 7897
4164 7895
FORECASTER: STEINBUGLThe State College radar (KCCX), 78 km away, was scanning. The volume nearest the first event began at 08:54 UTC.
2 thunderstorm wind. Local standard time, as filed.
A narrow line of heavy showers with estimated winds near 60 mph knocked down trees between St. Mary's and Johnsonburg.
A narrow line of heavy showers with estimated winds near 60 mph brought down utility wires and caused power outages in Stoystown.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2013Every state in 2013This day in weather historyWarnings in Pennsylvania, December 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: 481972, 481971.