An intense and rapidly developing low pressure system helped produce heavy snow over the higher terrain of the Poconos on the 28th.  A heavy precipitation band was able to chill the atmosphere to snow also over Bucks and Montgomery Counties Pennsylvania during the mid day hours on the 28th. This was an elevation driven event in the Poconos, as very little snow accumulated in the valleys. It was a dynamically cooling driven event in the Philadelphia northwest suburbs where the accumulating snow coincided with the heaviest precipitation rates. Highest accumulations in the Poconos reached 17 inches; in the northwest Philadelphia suburbs around 3.5 inches.
In the Poconos, the rain began during the afternoon of the 27th. Over the higher terrain, precipitation changed to snow during the late evening. Precipitation fell as snow until it ended during the early evening of the 28th. The heaviest snow fell between 8 a.m. and 6 p.m. EDT on the 28th. In the valleys, precipitation type was intensity driven. When precipitation became heavier, it changed to snow, lighter it went back to rain. This meteorological process is called dynamic cooling in which so much snow is falling from aloft that the amount of heat needed to melt the snow, cools the surrounding air where it can support snow at a lower level to the point it can reach the ground. Once the snow intensity weakens, warmer surrounding air moves in and raises temperatures and the snow then melts before reaching the ground.  A similar precipitation event like this one occurred in New York State in September of 1987. This same process occurred in Bucks and Montgomery Counties around mid-day on the 28th as the rain changed to an accumulating snow for around four hours. Meanwhile precipitation started as rain the previous evening and ended as rain late in the afternoon on the 28th.
The combination of the heavy wet snow, some leaves still on trees and very strong winds led to many traveling problems as well as downed trees and wires in the Poconos. Many school districts never opened; a few others had early dismissal. A seven mile stretch of Interstate 80 was repeatedly closed between the Pennsylvania Turnpike Extension in Carbon County and Pennsylvania State Route 115 in Monroe County because of multiple tractor-trailer and vehicular accidents between 9 a.m. EDT and Noon EDT on the 28th. Many accidents were also reported on Pennsylvania State Route 940 in Monroe County. Pennsylvania State Route 423 in Tobyhanna (Monroe County) was closed. A downed large tree caused road closures in Lehighton. Pennsylvania Power and Light reported about 60,000 customers lost power throughout their eastern Pennsylvania service area with more than 400 separate cases. The ten thousand homes and businesses that lost power in Monroe County were concentrated in Tobyhanna and Coolbaugh Townships. An emergency shelter was opened in Coolbaugh Township. In Carbon County outages were reported in Kidder, Penn Forest and East Side. Power was not fully restored until the 30th.
In the Philadelphia northwest suburbs, Bucks County took the brunt of the reported damage from the combination of the accumulating wet snow and strong winds. About 10,000 homes and businesses lost power with the brunt of the outages in Warminster and Northampton Townships. Many trees still had leaves on them. Roadways were blocked by downed trees in Bristol, Langhorne and Middletown. A vehicle in West Rockhill Township skidded into a wooded area. Seven school districts cancelled after school activities. The weather forced the cancellation of a presidential campaign stop in Quakertown by United States Senator John McCain.
Snowfall totals included 17.0 inches in Tobyhanna (Monroe County), 7 inches in Penn Forest (Carbon County), 6 inches in Albrightsville (Carbon County), 4.5 inches in Pocono Summit (Monroe County), 3.6 inches in Richboro (Bucks County), 3.0 inches in Langhorne (Bucks County), 2.5 inches in Perkasie (Bucks County), 2.0 inches in Montgomeryville (Montgomery County) and Chalfont (Bucks County) and 1.5 inches in Fairless Hills (Bucks County) and Souderton (Montgomery County). The 17 inches that accumulated in Tobyhanna matched a record for the earliest and heaviest snowfall for the Poconos. According to the Pocono Weather Book by meteorologist Ben Gelber, a 17 inch snowfall also occurred on October 16th to 17th in Freeland (Luzerne County) in 1977.
A cold front moved through the region on the 27th and stalled offshore. A low pressure system developed on the stalled front over North Carolina on the afternoon of the 27th. It slowly moved northeast and intensified rapidly. By 2 a.m. EDT on the 28th it was just off the New Jersey Coast and had a central pressure of 1003 millibars. At 8 a.m. EDT on the 28th, the low pressure system was approaching central Long Island, New York and the pressure lowered to 995 millibars. It proceeded to move northeast and was a 989 millibar low pressure system near Hartford, Connecticut at 2 p.m. EDT on the 28th and a 986 millibar low pressure system along the northern Vermont and New Hampshire border at 8 p.m. EDT on the 28th. A closed upper level low moved through the region during the day on the 28th. The relatively colder air at its center coupled with the heavy precipitation intensity made it possible for the rain to change to snow in parts of the region.

Heavy Snow in MONROE, PENNSYLVANIA
From 27-OCT-08 21:00:00 to 28-OCT-08 18:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Heavy Snow in CARBON, PENNSYLVANIA
From 27-OCT-08 22:00:00 to 28-OCT-08 18:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in BUCKS, PENNSYLVANIA
From 28-OCT-08 09:00:00 to 28-OCT-08 13:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in MONTGOMERY, PENNSYLVANIA
From 28-OCT-08 09:00:00 to 28-OCT-08 13:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter