Gusty west winds and low temperatures combined to produce very low wind chills across the region.
Every event with a place to put it; 23 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.
Gusty west winds and low temperatures combined to produce very low wind chills across the region.
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 Feb 5, 3:41 PM EST, 19 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 341 PM EST MON FEB 5 2007 .SHORT TERM /TONIGHT/... MORE OF THE SAME TONIGHT WITH ARCTIC HIGH AND W/NW FLOW. LOWS MAY BE JUST SLIGHTLY WARMER THAN LAST NIGHT WITH HEIGHTS SUBTLY HIGHER...BUT IN GENERAL TEMPS WILL BE SIMILAR TO LAST NIGHT. WINDS WILL NOT BE QUITE AS STRONG HOWEVER...KEEPING WIND CHILLS IN THE ADVISORY AREA IN THE ADVISORY CATEGORY (ALTHOUGH CAMBRIA/SOMERSET MAY BUMP -25F FROM TIME TO TIME). WILL ALSO EXPAND THE WC.Y FURTHER SOUTH TO COVER THE REMAINDER OF THE CWA AS GRIDDED DATABASE QUERY INDICATES CRITERIA WILL BE MET/EXCEEDED FURTHER SOUTH. THIS ALSO LINES UP WELL WITH LWX TO THE SOUTH. WILL RUN IT...LIKE THE ADY ALREADY IN EFFECT...UNTL 17Z TUE. LAKE EFFECT SNOWS WILL CONTINUE TO JUST BRUSH THE NW CORNER OF CWA. COULD SEE AN INCH OR SO OF FRESH ACCUMULATION N AND W OF WARREN...OTHERWISE JUST SOME SCATTERED LIGHT SNOW SHOWERS FOR THE NW MTNS OVERNIGHT. && .LONG TERM /TUESDAY THROUGH MONDAY/... IN SHORT...COLD AND DRY WILL SUM UP THE WEATHER OVER THE NEXT SEVERAL DAYS IN THE LONG TERM PD. NOW FOR THE DETAILS...AN ALBERTA CLIPPER DIVING ESEWD THRU THE UPPER MISSISSIPPI VALLEY EARLY TUE IS FCAST TO REACH THE LWR OH VLY BY 00Z WED. MODEL DIAGS OF PREVIOUS RUNS FROM YESTERDAY AS WELL AS TODAYS MODEL SUITE CONTINUES TO RECOMMEND/FAVOR A SOLN CLOSER TO THE GFS WITH SUPPORT FROM SREF/MREF ENS MEANS. HPC HAD NOTED OVERNIGHT THAT THE FLOW ALOFT IN THE NAM SEEMS TOO AMPLIFIED...LEADING TO A SLOWER AND DEEPER SFC WAVE. DESPITE THE NAM SHOWING GOOD RUN-TO-RUN CONTINUITY WITH RESPECT TO THE PREVIOUS TRENDS WITH THIS CLIPPER SYS...IT STILL APPEARS TO BE AN OUTLIER THIS PACKAGE GIVEN THE FAST/FLAT NATURE OF THE UPPER LVL FLOW. GIVEN THAT THE S/W IS EMBEDDED WITHIN THIS FAST FLOW...A SOLN MORE ALIGNED WITH THE GFS IS PREFERRED. THE AFOREMENTIONED CLIPPER SYSTEM WILL BRING A BRIEF PD OF WARM ADVECTION -SN TO MAINLY THE SRN 1/3 OF THE CWA FROM LATE TUE EVE INTO EARLY WED. THE GFS SHOWS A GOOD SURGE OF THETA-E ADV ALONG AND SOUTH OF THE MASON-DIXON LINE WITH FORCING AND ISENTROPIC LIFT ALONG THE 275-285K RIBBON INCREASING BELOW A THERMALLY INDIRECT 140KT JET STREAK. THE WEAK SFC LO REFLECTION SLIDES EWD THRU THE SRN MID ATLANTIC STATES AND OFFSHORE BY 12Z WED. SFC RIDGING QUICKLY BUILDS IN FROM THE WEST...SHUTTING OFF THE PRECIP BY LATE WED MORN/EARLY AFT. THE LLVL MAY BACK ENUF IN THE WAKE OF THE S/W TO BRING SOME LAKE SNOWS INTO THE NW COS...BUT GUID STILL INDICATING MORE OF A GNRL WRLY FLOW SO HAVE HELD POPS IN THE CHC CAT ACROSS THE NW MTNS WITH LITTLE IN THE WAY OF ACCUMS. HAVE INCREASED POPS ACROSS THE FAR SRN TIER COS ALONG AND SOUTH OF THE PA TURNPIKE TO LKLY /60%/ WHICH IS MORE IN LINE THE THE 09/15Z SREF 0.05/0.10 PROBS. HAVE BLENDED MODEL QPF FIELDS WITH HPC AND HAVE COME UP WITH SNOW AMOUNTS FROM 0.5-1.5 ACROSS THIS AREA WITH THE HIGHER AMOUNTS PSBL OVER THE HIGHER TERRAIN OF THE LAUREL/SCENT MTNS. THESE AMOUNTS AGREE WITH THE 09/15Z SREF PLUME DIAGRAMS WHICH SHOW AROUND AN INCH OR SO IN THE MEAN AT JOHNSTOWN AND SOMERSET...WITH A TAD LESS A BIT FURTHER N AT ALTOONA. IN GENERAL...SHOULD SEE LESSER AMOUNTS THE FURTHER NORTH AND EAST ONE GOES WITH LITTLE MORE THAN A FLURRY IN THE FAR NE PORTION OF THE CWA. HAVE GONE WITH ENS MOS BLEND FOR TEMPS EARLY IN THE PD WHICH REMAIN FAIRLY COLD AND REMAIN BELOW NORMAL. FOLLOWED HPC GUID IN THE LATER PDS WITH BLEND FROM THE 06/12Z GFS. MAIN THEMES IN THE MEDIUM TO LONG RANGE CONTINUE TO BE DRY WX AND BELOW NORMAL TEMPS WITH THE EXCEPTION OF SOME -SHSN ACROSS THE NW MTNS CLOSE TO LAKE ERIE. DIFFERENCES/UNCERTAINTY IN THE DETAILS OF THE EXTNDD REMAIN THE SAME WITH EACH MODEL HANDLING EMBEDDED S/W DISTURBANCES A LITTLE DIFFERENTLY. BASIC PATTERN SHOULD NOT CHANGE MUCH INTO THE WKEND AS THE 06/12Z MREF/GEFS ENS MEANS CONTINUE TO SHOW TROFING OVER THE ERN PAC AND ERN NOAM WITH POSITIVE HEIGHT ANOMALIES WEAKENING OVER NWRN CANADA/AK AND RIDGING OVER THE WCENT CONUS. ENSEMBLE GUID AS WELL AS OPERATIONAL GFS/ECMWF STILL WANT TO FLATTEN THE UPPER LEVEL FLOW AND MOVE THE MEAN ERN TROF NEWD BY EARLY NEXT WEEK WITH A RETURN TO A SLIGHTLY MORE MILDER...QUASI-ZONAL FLOW TYPE PATTERN PREVAILING ACROSS THE CONUS. THIS WOULD ALSO LEAD A MODERATION IN TEMPERATURES...ALLOWING THEM TO RETURN TO MORE SEASONABLE LEVELS BY EARLY NEXT WEEK. && .AVIATION /21Z-18Z/... NOT MUCH TO WORRY ABOUT TODAY FOR THE MAJORITY OF AVIATION SITES ACROSS CTP CWA. OFF AND ON CLOUDS PRODUCING OCCASIONAL MVFR...BUT VFR FOR A VAST MAJORITY OF THE TIME/REGION. WINDS WILL SLACKEN A LITTLE OVERNIGHT. CLOUDS ASSOCIATED WITH THE NEXT SYSTEM BEGIN TO MOVE INTO THE AREA DURING THE DAY TOMORROW...BUT THE TRANSITION IS GOING TO BE TOO CLOSE TO THE END OF THE TAF AND INSIGNIFICANT TO AVIATION TO WARRANT ITS INCLUSION. AS FOR KBFD...LAKE EFFECT ON A DOWNWARD TREND...RESULTING IN SCATTERED SNOW SHOWERS TO THE WEST OF LAKE ERIE. WITH THE LAKE FREEZING OVER...THE HEIGHT OF THE INVERSION DROPPING...AND WIND SHEAR/DIRECTION BECOME INCREASINGLY UNFAVORABLE...DO NOT EXPECT MUCH FROM THE ACTUAL SNOW SHOWERS. THE MAIN ISSUE IS THE WIND AND RESULTANT BLOWING SNOW...WHICH WILL CONTINUE TO PRODUCE THE LOW VIS WE SEE CLOSE TO THE SURFACE THROUGH MUCH OF THE PERIOD. && .CTP WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY UNTIL 11 AM EST TUESDAY FOR PAZ004>006- 010>012-017>019-024>028-033>037-041-042-045-046-049>053- 056>059-063>066. && SHORT TERM...RXR LONG TERM...STEINBUGL AVIATION...CONNELLY
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE STATE COLLEGE PA 533 AM EST MON FEB 5 2007 PAZ004>006-010>012-017-018-024-033-037-041-042-061045- WARREN-MCKEAN-POTTER-ELK-CAMERON-NORTHERN CLINTON-CLEARFIELD- NORTHERN CENTRE-CAMBRIA-SOMERSET-TIOGA-NORTHERN LYCOMING-SULLIVAN- 533 AM EST MON FEB 5 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT DANGEROUSLY COLD WIND CHILLS OF 25 TO 30 BELOW ZERO WILL OCCUR THROUGH LATE THIS MORNING...PROMPTING A WIND CHILL WARNING FOR THE REGION THROUGH 11 AM. THE WIND CHILL WARNING WILL BE REPLACED WITH A WIND CHILL ADVISORY AFTER 11 AM FOR THE REMAINDER OF THE DAY AS WIND CHILLS REMAIN BETWEEN 10 AND 20 BELOW ZERO. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY DEPENDING ON THE STRENGTH OF WINDS TONIGHT...A WIND CHILL WARNING MAY AGAIN BE NEEDED OVERNIGHT INTO TUESDAY MORNING. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED. PAZ019-025>028-034>036-045-046-049>053-056>059-063>066-061045- SOUTHERN CENTRE-BLAIR-HUNTINGDON-MIFFLIN-JUNIATA-BEDFORD-FULTON- FRANKLIN-SOUTHERN CLINTON-SOUTHERN LYCOMING-UNION-SNYDER-MONTOUR- NORTHUMBERLAND-COLUMBIA-PERRY-DAUPHIN-SCHUYLKILL-LEBANON- CUMBERLAND-ADAMS-YORK-LANCASTER- 533 AM EST MON FEB 5 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT A WIND CHILL ADVISORY IS IN EFFECT THROUGH 11 AM AS WIND CHILLS WILL REACH 10 TO 20 BELOW ZERO THROUGH LATE THIS MORNING. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY DEPENDING ON THE STRENGTH OF WINDS TONIGHT...A WIND CHILL ADVISORY MAY AGAIN BE NEEDED OVERNIGHT INTO TUESDAY MORNING. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED. GARTNER/MARTIN
The national radar mosaic for the moment the first event began.
23 extreme cold/wind chill. Local standard time, as filed.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
Temperatures in the single digits, combined with west winds of 10 to 20 mph, produced wind chills of 10 to 15 degrees below zero.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2007Every state in 2007This day in weather historyWarnings in Pennsylvania, February 2007
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: 7649, 7650, 7651, 7652, 7653, 7654, 7655, 7656, 7657, 7658, 7659, 7660, 7661, 7662, 7663, 7664, 7665, 7666, 7667, 7668, 7669, 7670, 7671.