January 25 2000
The most intense and widespread winter storm since the Blizzard of 1996 buried Eastern Pennsylvania on the 25th
with around 12 inches of snow. The low pressure system responsible for the winter storm began as a weak low pressure
system on a stationary front in southern Texas on the 23rd. By the morning of the 24th, it was located in the northeastern
Gulf of Mexico near Apalachicola, Florida. Initial projections were for this storm system to stay far enough offshore for
the heaviest precipitation to fall over the ocean and a more significant storm was expected on Wednesday the 26th. But, by
Monday evening the 24th, it became apparent that the storm would not safely go out to sea. In fact, it was intensifying and
hugging the South Atlantic Coast. By 7 a.m. EST on the 25th, it was about a 980 millibar low just northeast of Cape Hatteras.
The storm's greatest intensification was over, but it moved northeast near the Atlantic Seaboard, instead of
eastnortheast as was originally expected.
The snow began with a vengeance between 4 a.m. and 7 a.m. EST across Eastern Pennsylvania. Snowfall rates of
around 2 inches per hour were common during the first couple hours of this storm. By the morning rush hour, several inches
had already accumulated around the Philadelphia area.
After sunrise, as warmer air came in above the ground and the precipitation intensity slackened, the snow began
mixing with and changing over to sleet and freezing rain across Southeast Pennsylvania. It was still snowing across the rest
of Eastern Pennsylvania, but at a lighter rate.
Nevertheless by mid morning there was already 5 inches of snow on the ground in Berks County and by noon, there
was already 6 inches of new snow in Stroudsburg (Monroe County). Southeast Pennsylvania spent most of the daylight hours
in the storm's "dry slot" - an area of lighter precipitation. As colder air became more deeply entrenched, after 2 p.m. EST,
the wintry mix started to change to sleet and then snow. Precipitation was mainly snow with a little sleet mixed in around
Philadelphia during the evening.
The change to mainly snow coincided with another heavier band of precipitation that affected Eastern Pennsylvania
during the evening of the 25th. The snow ended by Midnight EST.
Total Accumulations (going from northwest to southeast across the region) included: in Monroe County 13 inches
in Saylorsburg, 11 inches in Long Pond, 10 inches in Bossardsville and East Stroudsburg, 7 inches in Scotia and 6.5 inches
in Pocono Summit; in Northampton County, 14 inches in Williams Township and 7 inches in Bath; in Lehigh County 10 inches at
the Lehigh Valley International Airport, 7 inches in Allentown; in Berks County 11 inches at the Blue Marsh Lake, 10 inches
in Morgantown and Vinemont, 8 inches in Kutztown and Lincoln Park; in Chester County 12 inches in Kennett Square and West
Barlborough Township, 11 inches in Downingtown and West Chester, 9 inches in Coatesville and 8 inches in Honey Brook and Glenmoore;
in Montgomery County 14 inches at the Willow Grove NAS, 12 inches in Wynnewood, 11.5 inches in Norristown, 11 inches in King
of Prussia and 7 inches in Pottstown; in Bucks County 13.6 inches in Chalfont, 12.5 inches in Furlong, 12 inches in Doylestown
and 9 inches in Springtown and Langhorne; in Delaware County 11 inches in Springfield and 9 inches at the Philadelphia International
January 20 2001
A vigorous upper air disturbance coupled with a low pressure system that was intensifying east of the New Jersey
coast produced heavy snow across Eastern Pennsylvania.
Precipitation started again as snow across most of Eastern Pennsylvania during the late afternoon and early evening
of the 20th. In and around the local Philadelphia area, where the air mass was warmer, precipitation started as rain. During
the evening precipitation then changed to sleet and then snow and by 10 p.m. EST it was snowing throughout Eastern Pennsylvania.
The heaviest precipitation, thus the largest accumulation of snow fell in a band from Lancaster County northeastward through
the Lehigh Valley. Accumulations ranged from three to twelve inches. The upper air disturbance was so strong that thunderstorms
were reported in Delaware County and the Lehigh Valley. The snow ended shortly after daybreak on the 21st, except in the Poconos
where it lingered throughout most of the morning.
Specific accumulations included 12 inches in Camelback Mountain (Monroe County) and Morgantown (Berks County),
10.8 inches in Williams Township (Northampton County), 8.3 inches in Reading (Berks County), 8.1 inches in Glenmoore (Chester
County), 8 inches in Sellersville (Bucks County), Macungie (Lehigh County) and Saylorsburg (Monroe County), 7.6 inches in
Boyertown (Berks County), 7.5 inches in Albrightsville (Carbon County), 7 inches in at the Lehigh Valley International Airport
and Pottstown and Green Lane (Montgomery County), 6.5 inches in Downingtown (Chester County), 6.3 inches in East Stroudsburg
(Monroe County), 6 inches in Fricks (Bucks County), 5.3 inches in Somerton (Philadelphia), 5 inches in Wynnewood (Montgomery
County), 4.5 inches in Hamburg (Berks County), Jim Thorpe (Carbon County) and Valley Forge (Chester County), 4 inches in Clifton
Heights and Crum Creek (Delaware County) and 3.6 inches at the Philadelphia International Airport.
February 5 2001
The low pressure system responsible for the heavy snow developed along a stationary front just east of Florida
on the 4th. By the morning of the 5th, it moved north to near Elizabeth City, North Carolina. It then intensified rapidly
(a drop of about 25 millibars during the next 24 hours) as it moved northeast and reached Nova Scotia during the morning of
the 6th. The air mass over the region was marginally cold for snow, especially around Philadelphia. But, the precipitation
intensity was so great (storm total water equivalents were around 1.5 inches), that the heat required to melt the snow aloft
(called the latent heat of fusion) chilled the air mass and made the snow capable of reaching the ground. This type of snowstorm
is typically called a "warm snowstorm" because the low pressure system itself manufactures the cold air needed to make the
snow reach the ground.
Specific accumulations included in Berks County: Mohnton 14.5 inches, Bechtelsville 13 inches, Reading 10 inches
and Lincoln Park 9.5 inches, in Bucks County: 18 inches in Springtown, 14.7 inches in Chalfont, 13.5 inches in Sellersville,
8 inches in Doylestown and 4 inches in Levittown, in Carbon County: 11 inches in Albrightsville, 10 inches in Meckesville
and 9 inches in Jim Thorpe and Lehighton, in Chester County: 11 inches in Kimberton, 10 inches in Exton, 7.4 inches in Glenmoore,
6 inches in Valley Forge and 4 inches in Oxford. In Delaware County: 12.4 inches in Radnor, 7.5 inches in Newtown and 4 inches
in Crum Creek, In Lehigh County: 17.5 inches in Coopersburg, 17 inches in Salisbury Township, 16 inches in Alburtis and 13
inches at the Lehigh Valley International Airport, in Monroe County: 16 inches in Saylorsburg, 13.5 inches in East Stroudsburg,
12 inches in Scotia and 10 inches in Pocono Summit, In Montgomery County: 14 inches in Palm, 13 inches in King of Prussia,
12 inches in Pottstown, 11 inches in Hatfield and 9 inches in Whitemarsh, in Northampton County: 18 inches in Williams Township,
17 inches in Palmer Township, 13 inches in Easton and 12 inches in Bethlehem and in Philadelphia County: 8 inches in Manayunk,
5.5 inches in Somerton, 4 inches at the Franklin Institute and 3 inches at the Philadelphia International Airport.