A large arctic high pressure system moved toward the area during the 16th and 17th. The extent of the arctic air mass kept maximum temperatures only in the teens, with even some single digits across northeastern Pennslyvania. The minimum temperatures dropped into the single digits, however some areas where the wind was able to drop off considerably, mainly in the northeastern part of the state, dropped to well below zero. As a storm system remained well to the northeast, the combination of this along with strong arctic high pressure to the west allowed for gusty winds. This produced wind chill values to zero and below zero for awhile across eastern Pennsylvania, especially during the nighttime hours. However, the higher elevations in northeastern Pennsylvanina experienced the full force of the brutally cold air mass as Mount Pocono had a wind chill of 21 degrees below zero for a time during the early morning hours of the 16th and 27 degrees below zero for a time during the early morning hours of the 17th.
The Allentown Rescue Mission (Lehigh County) reported that they only provided shelter during the arctic blast of the 14th through the 17th to only men who have vouchers from police. The Lehigh County Conference of Churches walked streets and offered shelter and blankets to the city���s homeless. The arctic blast began around 12th as some communities already established some actions. A code blue was called for the week of the 12th by Philadelphia officials (Philadelphia County). Residential and health outreach teams in the city were mobilized to help people living on the streets. The Montgomery County Health Department issued a code blue on the 10th and continued it through 12:00 PM EST on the 12th. The Bangor Area High School (Northampton County) closed on the 14th because of frozen pipes. Students were dismissed at 9:15 AM EST because there was no water. The Safe Harbor homeless shelter on Bushkill Street in Easton (Northampton County) filled its 27 beds as people living on the streets seeked a warm place to stay. Officials at the American Red Cross Lower Bucks County Chapter on the 14th reported that they were ready to deal with the impending arctic chill. Their shelter on New Falls Road in Bristol Township was already at capacity with 75 people and a waiting list was growing. If needed, the township reported that the facilities library could be converted into a dorm with 10 extra cots. Arctic air along with bitterly cold wind chills on the 15th lead to several schools having a two hour delay in Carbon County.
The 17th was the coldest morning in awhile across the region. The low temperature at the Philadelphia International Airport (Philadelphia County) dropped to 6 degrees. This was the coldest since January 28, 2005 when the low was also 6 degrees. The Lehigh Valley International Airport (Lehigh County) dropped to 2 degrees below zero. This was the coldest since December 14, 2005 when it was 2 degrees below zero. The Reading Airport (Berks County) dropeped to 1 degree, which was the coldest since January 10, 2004 when it was 1 degree.
Some low temperatures on the 16th included; 4 degrees below zero in Mount Pocono (Monroe County), 7 degrees at the Lehigh Valley International Airport (Lehigh County), 8 degrees in Doylestown (Bucks County), 9 degrees in Willow Grove (Montgomery County), 10 degrees in Pottstown (Montgomery County), 11 degrees at the Reading Airport (Berks County), 13 degrees at the Philadelphia International Airport (Philadelphia County), and 14 degrees at the Northeast Philadelphia Airport (Philadelphia County).
Some low temperatures on the 17th included; 14 degrees below zero in Mount Pocono (Monroe County), 2 degrees below zero at the Lehigh Valley International Airport (Lehigh County), 1 degree at the Reading Airport (Berks County), 2 degrees in Pottstown (Montgomery County), 2 degrees in Doylestown (Bucks County), 4 degrees in Willow Grove (Montgomery County), 6 degrees at the Philadelphia International Airport (Philadelphia County), and 8 degrees at the Northeast Philadelphia Airport (Philadelphia County).

Cold/Wind Chill in BERKS, PENNSYLVANIA
From 16-JAN-09 22:00:00 to 18-JAN-09 10:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Cold/Wind Chill in BUCKS, PENNSYLVANIA
From 16-JAN-09 22:00:00 to 18-JAN-09 10:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Cold/Wind Chill in CARBON, PENNSYLVANIA
From 16-JAN-09 20:00:00 to 18-JAN-09 12:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Cold/Wind Chill in CHESTER, PENNSYLVANIA
From 16-JAN-09 22:00:00 to 18-JAN-09 10:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Cold/Wind Chill in DELAWARE, PENNSYLVANIA
From 16-JAN-09 22:00:00 to 18-JAN-09 10:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Cold/Wind Chill in LEHIGH, PENNSYLVANIA
From 16-JAN-09 22:00:00 to 18-JAN-09 10:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Cold/Wind Chill in MONROE, PENNSYLVANIA
From 16-JAN-09 20:00:00 to 18-JAN-09 12:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Cold/Wind Chill in MONTGOMERY, PENNSYLVANIA
From 16-JAN-09 22:00:00 to 18-JAN-09 10:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Cold/Wind Chill in NORTHAMPTON, PENNSYLVANIA
From 16-JAN-09 22:00:00 to 18-JAN-09 10:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Cold/Wind Chill in PHILADELPHIA, PENNSYLVANIA
From 16-JAN-09 22:00:00 to 18-JAN-09 10:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS