A potent low pressure system in the Ohio Valley during the early morning hours of May 11th moved eastward and gradually weakened. A secondary low formed over northeastern North Carolina during the late afternoon on the 11th and eventually absorbed the other low pressure system, becoming the dominant storm. This storm gradually moved east northeastward late on the 11th into the 12th. Early on the morning of the 12th, the storm was centered over the southern Delmarva. As this storm strengthened fairly rapidly, a strong northeast wind developed and persisted through the evening of the 12th. The prolonged northeast flow combined with higher than normal tides, which caused tidal flooding in New Jersey along the Delaware River and Delaware Bay. There was limited moisture inland from the center of the storm. By the evening of the 12th, the coastal storm tracked eastward and gradually moved away from the region.
A number of Cumberland County residents remained without power on the 13th following high winds and heavy rains on the 12th. Atlantic City Electric reported on the 13th that crews continued to work to restore power to some 200 customers who lost power during the storm. The majority of the outages on the 12th were caused by downed trees and tree limbs. Utilities reported more than 60,000 customers were without power in New Jersey. A large portion of a tree limb fell onto the roof of a home in Upper Deerfield (Cumberland County) on the 13th after heavy rain and strong winds compromised the trunk. There were numerous reports of tree limbs and other debris on Salem County roadways. The Red Cross set up a shelter for Pennsville (Salem County). In Bridgeton (Cumberland County), eight reports of downed trees or large limbs blocking roadways were received between 1:00 AM EDT and 1:00 PM EDT on the 12th, with the bulk of that activity having occurred between 10:00 AM EDT and 11:00 AM EDT. Several trees were downed in Vineland (Cumberland County), with a couple which fell across public streets and one tree hit a house. The home suffered considerable damage as the front of the structure was torn off. The Department of Streets in Millville (Cumberland County) reported that six streets were blocked by fallen trees. In Cumberland County, a wind gust to 64 mph was reported in Fortescue during the night of the 11th and early morning of the 12th.
An east wind drove in the tide, which filled marshes with water, into parts of coastal Cumberland County. Roads into Gandy's Beach and Money Island were impassable, as they were covered with debris and with two feet of sand over the road in at least one place. As a result, the sand needed to be bulldozed away. Floating propane tanks also presented a problem in Downe (Cumberland County). Five or six were recovered floating in the Gandy's Beach-Money Island area and another half-dozen in Fortescue (Cumberland County). At 2:00 PM EDT on the 12th, 3,900 Atlantic City Electric customers were without power across Cumberland County. By 9:15 PM EDT on the 12th, that number had dropped considerably.
In Salem County, reports started to arrive into the 911 Center around 2:30 AM EDT on the 12th regarding downed trees and debris blocking several roads. The following roads were closed due to flooding in Gloucester County; Route 322 at Route 130 southbound (Logan Township); Route 130 at High Hill Road (Logan Township); Center Square Road between Pedricktown Road and Route 130 (Logan Township); Route 44 at Crown Point Road (West Deptford Township). There was a report of a levee failure in Logan Township, and local resources were sent with concrete rip-raf to strengthen up the levee. In Burlington County, some trees were either snapped off or completely uprooted due to the rain and strong winds on the 12th, including in the Moorestown and Southampton areas. The New Jersey Turnpike restricted motorcycles and cars pulling trailers from using the highway on the 12th due to the strong winds.
Some peak wind gusts included; 57 mph in Tabernacle; 51 mph in Chatsworth Coyle Field; 50 mph in Bivalve; 48 mph at the Millville Airport; and 46 mph at McGuire Air Force Base.
Minor tidal flooding occurred along the Delaware River in Gloucester and Camden Counties as the Philadelphia tide gage peaked at 8.9 feet mean lower low water at 8:00 AM EDT on the 12th. Moderate tidal flooding was observered in Salem and Cumberland Counties. The Reedy Point, Delaware tidal gage reached 8.3 feet mean lower low water at 6:00 AM EDT on the 12th (moderate flooding begins at 8.2 feet mean lower low water). The Cape May Ferry Terminal tide gage, which is used for Cumberland County, reached 8.1 feet mean lower low water at 2:00 AM EDT on the 12th (moderate flooding begins at 7.7 feet mean lower low water). A newer tide gage at Delaware City, Delaware reached 9.1 feet mean lower low water at 6:00 AM EDT on the 12th. This was reported to be a record level since the gage was installed in 2001.