Saturday, February 18, 2012

Weather History: February 1987 Snowstorm

February 23rd (next Thursday) marks the 25th anniversary of that winter's biggest second snowfall in Philadelphia and the largest snowfall the Pennsylvania suburban areas picked up during that winter.  While a larger snowfall fell in the city in late January with a more potent storm, the February 1987 storm was a quick hitting thump of snow that brought over ten inches of snow in a short duration of time to many in the region.  In this case, the reverse held serve as a more "traditional" storm brought decent snows to the city and heavier snows to the city's north.

Energy pushed across the South along the jet stream, with a decent low pressure center hitting the Virginia coastline early in the morning on Monday 2/23.  This low intensified as it tracked off of the East Coast, with precipitation blossoming along the northern periphery of the storm low.  This deepening, along with a relatively decent cool air mass, allowed for much of the region to see snow from this storm system.  Light snow started late in the evening on the 22nd, continuing and intensifying as the night progressed into the 23rd until mid morning when snow ended.  However, in the nine hours where snow did in fact fall at the Airport, the city picked up 6.8".  In itself, a nice little storm.  The city total was not representative of the rest of the region, though.

Many suburban areas, as well as Northeast Philadelphia, picked up over a foot of snow.

Snowfall from this storm varied quite a bit by elevation, with parts of Chester County and Lancaster County picking up nearly two feet of snow (23.5" near Coatesville, 24" in Christiana in Lancaster County), with Wilmington getting between fourteen and eighteen inches of snow depending on location.   Snowfall during the peak of the storm fell at a rate of over three to four inches per hour, resulting on downed utility poles and numerous accidents in the suburbs.  The good news is much of this fell in the pre-dawn hours on a Monday morning, before work.  Greg Duffy, one of our regular readers on the site, measured twenty inches of snow in his driveway as a then-nine year old in Horsham, Montgomery County, and was kind enough to send along the photo seen above of the thumping of snow his neighborhood received.

To give an example of the sharp cutoff in snowfall to the north of us, snowfall amounts dropped quickly below five inches north of I-78 as places to the north of the Lehigh Valley picked up just a few inches, with Allentown picking up 6.5" at their Airport.

Other snowfall totals around the region included 17.5" in West Chester, 7.5" in Harrisburg, 6.6" in Atlantic City, and 2.9" in Scranton.