Strong Wind — Montgomery, Pennsylvania

2004-12-01 · Montgomery, Pennsylvania

Wider weather episode

The combination of a rapidly intensifying low pressure system and a strong cold frontal passage produced peak wind gusts of around 50 mph across Eastern Pennsylvania during the second half of the morning and throughout most of the afternoon of the 1st. The peak wind gusts occurred from the time of the cold frontal passage (between 10 a.m. and 11 a.m. EST) into the first half of the afternoon. A 50-year-old man was killed by a fallen tree in Montgomery County. Numerous weaker trees and limbs and subsequently power lines were knocked down. The wind strewed garbage and recycling pails. The wind damage was exacerbated by the recent wet weather which made the ground soft and the prolonged duration of the stronger winds. Over 100,000 homes and businesses lost power across Eastern Pennsylvania. In the greater Philadelphia Metropolitan area, in Whitemarsh Township (Montgomery County), a 50-year-old man was crushed and killed by a fallen pine tree on Caramoor Farm. PECO Energy reported about 103,000 of its customers lost power due to the downed trees, tree limbs and wires. The breakdown was approximately 39,500 in Delaware County, 26,500 in Chester County, 22,000 in Montgomery County, 9,000 in Bucks County and 6,000 within Philadelphia. All power was restored by the 2nd. In Philadelphia, construction material debris was blown off a Center City building. No injuries were reported. Trees were downed along the Schuylkill Expressway. In Montgomery County, some of the longer outages occurred in Springfield Township. In Hatfield Township, a house fire was caused by a toppled tree. The tree pulled down a power line which caused a power surge into the home's basement. In Delaware County, downed trees caused road closures in Chester Heights Borough and Newtown Township. In Newtown, a downed wire ignited a fire in the front yard of one home. A couple of schools dismissed children early because they lost power. In Chester County, a transformer fire occurred in East Bradford Township after its pole was knocked over. Many traffic lights were out throughout the county.In the Lehigh Valley and the Poconos, about 15,500 homes and businesses lost power. The strong winds ripped off a 100-foot by 40-foot section of bricks along the north wall of the Wachovia Bank Building in downtown Bethlehem (Northampton County). Several vehicles were damaged and the building was evacuated for safety reasons. In Northampton County, power outages were reported, in Bath, Bangor, Bethlehem, Easton, Nazareth and Upper Mount Bethel. Outages in Lehigh County, outages were concentrated within Allentown.Peak wind gusts (from the west) included 58 mph in Downingtown (Chester County), 53 mph at the Northeast Philadelphia Airport, 52 mph at the Philadelphia International Airport, Mount Pocono (Monroe County), Reading (Berks County) and Willow Grove (Montgomery County), 51 mph in London Grove (Chester County), 48 mph in Pottstown (Montgomery County), 46 mph at the Lehigh Valley International Airport and 45 mph in Doylestown (Bucks County). The winds were caused by the surface pressure difference (gradient) between a high pressure system building northeast from the Gulf Coast States and an intensifying low pressure system that moved northeast through the Saint Lawrence Valley on the 1st. The strongest winds aloft occurred during the daytime hours and this coincided with the maximum daytime heating. The turbulent mixing that normally occurs when these two conditions coincide, efficiently mixed the stronger winds to the ground.

Source: NOAA Storm Events Database, event_id 5429521. Narrative written by the NWS forecast office that issued the report.