A broad area of low pressure extending from the Ohio Valley to the Piedmont of South Carolina consolidated off the Virginia Capes during the early morning of March 7th. This new primary low moved northeast and gradually deepened as it passed east of the Delaware and New Jersey Coasts on March 7th.
Precipitation gradually overspread the region during the overnight hours of March 6th to the 7th. Precipitation fell mainly as snow.
The snow fell heavy at times. Snowfall amounts generally ranged from 6 to 12 inches with localized amounts of 12 to 15 inches just north and west of I-95 in a swath from central Chester County northeast through central and southern Bucks County.  One emergency manager reported snowfall rates up to 4 inches per hour in thundersnow near Levittown (Bucks County).
The snow contained large amounts of liquid, making it heavy and wet. This led to downed trees, limbs, and wires resulting in numerous power outages.
Governor Wolf declared a State of Emergency for all of eastern Pennsylvania for the event.
The City of Philadelphia declared a Snow Emergency beginning at 8 AM Wednesday, March 7th based on anticipated conditions. City and state offices were closed, as were all public and parochial schools.
Montgomery County declared a Disaster Emergency from 7 PM Tuesday through 3 AM Thursday, March 8th.
A Declaration of Disaster Emergency was issued for Delaware County.  All government offices were closed.
Flights were cancelled at all the major airports due to the storm, and Amtrak cancelled at least some Wednesday service.
The heavy, wet snow, coupled with strong winds, caused power outages in addition to  existing power outages caused by the previous storm.  Hardest hit was Bucks County where up to 47,000 customers experienced power outages from this storm. In Montgomery County, approximately 12,000 customers lost power.  Up to 8,000 customers lost power in Delaware County from the storm. Monroe County experienced over 6,000 new power outages from this storm. Several hundred power outages were reported in Berks County.
The Port of Philadelphia was closed Wednesday, March 7th, and would reopen late the following day.

Winter Storm in WESTERN CHESTER, PENNSYLVANIA
From 06-MAR-18 20:00:00 to 07-MAR-18 15:00:00 (EST-5)
Reported by: Trained Spotter

Snow banding produced over a foot of snow in a very short period of time in a somewhat narrow strip oriented from southwest to northeast across the eastern portions of the county on March 7th.  Heavy snow began just before noon, falling at a rate of 3 to 4 inches per hour at times in thundersnow.  Area roadways were impassable through the afternoon and evening hours in this narrow strip.  Some reported snowfall totals include: 8.1 inches in Glenmoore, 8.0 inches in Coatsville, 6.8 inches in Exton, and 4.8 inches in Chester Springs.

Winter Storm in EASTERN CHESTER, PENNSYLVANIA
From 06-MAR-18 21:00:00 to 07-MAR-18 15:00:00 (EST-5)
Reported by: Trained Spotter

Snow banding produced over a foot of snow in a very short period of time in a somewhat narrow strip oriented from southwest to northeast across the eastern portions of the county on March 7th.  Heavy snow began just before noon, falling at a rate of 3 to 4 inches per hour at times in thundersnow.  Area roadways were impassable through the afternoon and evening hours in this narrow strip.  Some reported snowfall totals include: 13.0 inches in Wickerton, 11.3 inches in East Nantmeal, 9.0 inches in Berwyn, 8.8 inches in Chadds Ford, 8.0 inches in Valley Forge, 7.0 inches in Oxford, 4.8 inches in Nottingham, 4.3 inches in West Chester, and 2.8 inches in Devault.

Winter Storm in DELAWARE, PENNSYLVANIA
From 06-MAR-18 22:00:00 to 07-MAR-18 16:00:00 (EST-5)
Reported by: Trained Spotter

Snow banding produced over a foot of snow in a very short period of time in a somewhat narrow strip oriented from southwest to northeast across the central portions of the county on March 7th.  Heavy snow began just before noon, falling at a rate of 3 to 4 inches per hour at times in thundersnow.  Area roadways were impassable through the afternoon and evening hours in this narrow strip.  Some reported snowfall totals include: 12.0 inches in Broomall, 11.8 inches in Garnet Valley, 10.7 inches in Media, 10.5 inches in Chadds Ford, 9.2 inches in Wayne, 8.0 inches in Ridley Park, 7.5 inches in Lansdowne, and 5.8 inches in Drexel Hill.

Winter Storm in MONROE, PENNSYLVANIA
From 06-MAR-18 23:00:00 to 07-MAR-18 17:00:00 (EST-5)
Reported by: Trained Spotter

Snow was most intense in the higher elevations, where the highest snowfall totals occurred.  Some snowfall reports include: 12.4 inches in Bossardsville, 11.8 inches in Bartonsville, 10.3 inches near the Pocono County Club, 10.0 inches in East Stroudsburg, 9.5 inches in Pocono Summit, 9.2 inches at Mount Pocono, 8.5 inches in Long Pond, and 8.0 inches in Tobyhanna.

Winter Storm in CARBON, PENNSYLVANIA
From 06-MAR-18 23:00:00 to 07-MAR-18 16:00:00 (EST-5)
Reported by: Trained Spotter

Snow was most intense in the higher elevations, where the highest snowfall totals occurred.  Some snowfall reports include: 9.0 inches in Albrightsville, and 7.0 inches in 12.4 inches in Bossardsville, 11.8 inches in Lower Towamensing Township, and 4.0 inches in Lehighton.

Winter Storm in BERKS, PENNSYLVANIA
From 07-MAR-18 01:00:00 to 07-MAR-18 17:00:00 (EST-5)
Reported by: Trained Spotter

Higher elevations throughout the county experienced higher snowfall totals from this event.  Western portions of the county, far from the center of the coastal low, received less than 2 inches from the event. Some snowfall reports include: 10.5 inches in Huffs Church (elevation of 1000 feet), 9.1 inches near Fleetwood, 8.8 inches in Earl Township, 7.4 inches in Boyertown, 3.9 inches northwest of Reading, 2.5 inches near Kutztown, 2.1 inches southwest of Reading, 1.9 inches in Hamburg, and 1.5 inches in Wernersville.

Winter Storm in EASTERN MONTGOMERY, PENNSYLVANIA
From 06-MAR-18 23:00:00 to 07-MAR-18 15:00:00 (EST-5)
Reported by: Trained Spotter

Snow banding produced over a foot of snow in a very short period of time in a somewhat narrow strip oriented from southwest to northeast across the eastern portions of the county on March 7th.  Heavy snow began just before noon, falling at a rate of 3 to 4 inches per hour at times in thundersnow.  Area roadways were impassable through the afternoon and evening hours in this narrow strip.  Some reported snowfall totals include: 14.3 inches in Rosemont, 13.5 inches in Montgomeryville, 11.5 inches in Maple Glen, 11.0 inches in Bryn Mawr, 10.0 inches in Willow Grove, 8.6 inches in Jenkintown, 8.5 inches in King of Prussia, and 7.7 inches in Wynnewood.

Winter Storm in WESTERN MONTGOMERY, PENNSYLVANIA
From 06-MAR-18 23:00:00 to 07-MAR-18 16:00:00 (EST-5)
Reported by: Trained Spotter

Snow banding produced over a foot of snow in a very short period of time in a somewhat narrow strip oriented from southwest to northeast across the eastern portions of the county on March 7th.  Heavy snow began just before noon, falling at a rate of 3 to 4 inches per hour at times in thundersnow.  Area roadways were impassable through the afternoon and evening hours in this narrow strip.  Some reported snowfall totals include: 7.6 inches in Green Lane, 6.1 inches in Gilbertsville, 5.7 inches near Schwenksville, 5.3 inches in Graterford, 5.1 inches in Eagleville, 5.3 inches in Skippack, 4.3 inches in Limerick, and 3.0 inches near Geryville.

Winter Storm in PHILADELPHIA, PENNSYLVANIA
From 06-MAR-18 23:00:00 to 07-MAR-18 17:00:00 (EST-5)
Reported by: Trained Spotter

Snow banding produced over 8 inches of snow across the western portions of the county on March 7th with lesser amounts in the eastern and southern sections of the county.  Heavy snow began just before noon, falling at a rate of 1 to 2 inches per hour at times in thundersnow.  Area roadways were impassable through the afternoon and evening hours. Some reported snowfall totals include: 8.4 inches in Pencoyd (6ABC Studio), 8.2 inches in Fox Chase, 8.1 inches in Somerton, 7.0 inches in Roxborough, 6.1 inches at Philadelphia International Airport, 4.1 inches at the Franklin Institute, 3.9 inches in Spring Garden, and 3.0 inches in South Philadelphia.

Winter Storm in UPPER BUCKS, PENNSYLVANIA
From 07-MAR-18 00:00:00 to 07-MAR-18 18:00:00 (EST-5)
Reported by: Trained Spotter

Snow banding produced over a foot of snow in a very short period of time in a somewhat narrow strip oriented from southwest to northeast across the southern and central portions of the county on March 7th.  Heavy snow began just before noon, falling at a rate of 3 to 4 inches per hour at times in thundersnow.  Area roadways were impassable through the afternoon and evening hours in this narrow strip.  Some reported snowfall totals include: 12.0 inches in Bedminster, 9.0 inches in Springtown, 7.5 inches in Perkasie, 6.5 inches in West Rockhill Township, and 6.0 inches in Quakertown.

Winter Storm in LEHIGH, PENNSYLVANIA
From 07-MAR-18 01:00:00 to 07-MAR-18 17:00:00 (EST-5)
Reported by: Trained Spotter

Higher elevations throughout the county experienced higher snowfall totals from this event.  Some snowfall reports include: 7.8 inches in Washington Township, 7.6 inches in Werleys Corner, 7.3 inches in Neffs, 7.3 inches in Salisbury Township, 6.1 inches in Orefield, 5.3 inches in Emmaus, 4.0 inches in Macungie, and 3.4 inches at Lehigh Valley International Airport.

Winter Storm in NORTHAMPTON, PENNSYLVANIA
From 07-MAR-18 01:00:00 to 07-MAR-18 18:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Higher elevations throughout the county experienced higher snowfall totals in excess of 6 inches from this event.

Winter Storm in LOWER BUCKS, PENNSYLVANIA
From 07-MAR-18 01:00:00 to 07-MAR-18 18:00:00 (EST-5)
Reported by: Trained Spotter

Snow banding produced over a foot of snow in a very short period of time in a somewhat narrow strip oriented from southwest to northeast across the southern and central portions of the county on March 7th.  Heavy snow began just before noon, falling at a rate of 3 to 4 inches per hour at times in thundersnow.  Area roadways were impassable through the afternoon and evening hours in this narrow strip.  Some reported snowfall totals include: 16.0 inches in Richboro, 13.5 inches in Wrightstown Township, 13.2 inches in Newtown Grant, 11.1 inches in Langhorne, 10.5 inches in Lower Makefield Township, 10.3 inches in Doylestown, 9.5 inches in Morrisville, 7.5 inches in Washington Crossing, and 7.0 inches in Yardley.