The high pressure system responsible for third and last arctic blast of the month of February arrived in Pennsylvania on the morning of the 24th. Unlike the two previous arctic outbreaks earlier this month, this one was generally not accompanied by strong winds during the overnight and first half of the day. The one exception was in the Poconos where northwest winds of around 10 mph produced wind chill factors of around 25 degrees below zero during the pre-dawn hours.  Advisory level wind chills occurred until about 9 a.m. EST on the 24th.  Aside from the Poconos, air and wind chill temperatures were nearly the same. Nevertheless, the calm conditions and snow cover combined to give many non urban locations not only the coldest morning of the winter season, but one of the coldest mornings of the current century.  Morning low temperatures averaged 20 to 35 degrees colder than normal.
Lowest temperatures included 16 degrees below zero in Mount Pocono (Monroe County), 14 degrees below zero in East Stroudsburg (Monroe County), 8 degrees below zero at the Lehigh Valley International Airport, 5 degrees below zero in Boyertown (Berks County) and Quakertown (Bucks County), 4 degrees below zero in Gilbertsville (Montgomery County) and Furlong (Bucks County), 3 degrees below zero in Reading (Berks County) and Nazareth (Northampton County), 2 degrees below zero in Oxford (Chester County), 2 degrees above zero in West Chester (Chester County) and Horsham (Montgomery County), 5 degrees above zero in Newtown Square (Delaware County) and 7 degrees above zero at the Philadelphia International Airport.  The lowest hourly wind chill factor at Mount Pocono (Monroe County) was 27 degrees below zero.
The low temperature of 16 degrees below zero at Mount Pocono (Monroe County), not only broke the daily record low for February 24th dating back to 1914, but was also the lowest temperature of the winter and the lowest temperature of the present century.  The low temperature of 3 degrees below zero in Reading (Berks County), not only also broke the daily record low for February 24th dating back to 1914, but was the lowest temperature of the winter and the lowest temperature of the present century. It was the first sub zero minimum temperature of this century.  The low temperature of 8 degrees below zero at the Lehigh Valley International Airport, not only also broke the daily record low for February 24th dating back to 1948, but was the lowest temperature of the winter and the lowest recorded temperature since January of 1996.  The low temperature of 7 degrees above zero in Philadelphia did not establish a new daily record and the lowest temperature of the winter occurred on February 20th (2 degrees above zero).

The multiple arctic intrusions in Pennsylvania made this month one of the coldest Februaries on record. Since 1895, this February ranked as the 2nd coldest February on record with an average statewide temperature of 16.3 degrees (12.5 degrees below average). Only February of 1934 (15.2 degree average) was colder. At the Philadelphia International Airport, the February mean temperature of 25.8 degrees (9.9 degrees below average) was the 7th coldest February on record and the coldest since 1979 (23.0 degrees). At the Lehigh Valley  International Airport, the February mean temperature of 18.9 degrees (11.8 degrees below average) was the 2nd coldest February on record and the coldest since 1934 (16.6 degrees). At the Philadelphia International Airport, the February mean temperature of 25.8 degrees (9.9 degrees below average) was the 7th coldest February on record and the coldest since 1979 (23.0 degrees). In Reading (Berks County), the February mean temperature of 20.5 degrees was 11.8 degrees below average and in Mount Pocono (Monroe County), the February mean temperature of 13.5 degrees was 12.5 degrees below average.

Extreme Cold/Wind Chill in MONROE, PENNSYLVANIA
From 24-FEB-15 00:00:00 to 24-FEB-15 06:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Extreme Cold/Wind Chill in CARBON, PENNSYLVANIA
From 24-FEB-15 00:00:00 to 24-FEB-15 06:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Cold/Wind Chill in BERKS, PENNSYLVANIA
From 24-FEB-15 01:00:00 to 24-FEB-15 09:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Cold/Wind Chill in LEHIGH, PENNSYLVANIA
From 24-FEB-15 01:00:00 to 24-FEB-15 09:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Cold/Wind Chill in WESTERN MONTGOMERY, PENNSYLVANIA
From 24-FEB-15 01:00:00 to 24-FEB-15 09:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Cold/Wind Chill in LOWER BUCKS, PENNSYLVANIA
From 24-FEB-15 01:00:00 to 24-FEB-15 09:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Cold/Wind Chill in PHILADELPHIA, PENNSYLVANIA
From 24-FEB-15 02:00:00 to 24-FEB-15 08:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Cold/Wind Chill in DELAWARE, PENNSYLVANIA
From 24-FEB-15 02:00:00 to 24-FEB-15 08:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Cold/Wind Chill in EASTERN CHESTER, PENNSYLVANIA
From 24-FEB-15 01:00:00 to 24-FEB-15 09:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Cold/Wind Chill in UPPER BUCKS, PENNSYLVANIA
From 24-FEB-15 01:00:00 to 24-FEB-15 09:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Cold/Wind Chill in EASTERN MONTGOMERY, PENNSYLVANIA
From 24-FEB-15 01:00:00 to 24-FEB-15 09:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Cold/Wind Chill in NORTHAMPTON, PENNSYLVANIA
From 24-FEB-15 01:00:00 to 24-FEB-15 09:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Cold/Wind Chill in WESTERN CHESTER, PENNSYLVANIA
From 24-FEB-15 01:00:00 to 24-FEB-15 09:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS