After fluctuating in intensity for four days, Isabel gradually weakened and made landfall on the Outer Banks of North Carolina with winds of 105 mph (169 km/h) on September 18.

The storm's center remained to the south and west of Delaware, and was about 175 miles (282 km) from the state at its closest approach.

[3] Though located within the cone of uncertainty, all subsequent forecasts predicted a landfall on North Carolina with the hurricane passing to the west of the state.

The declaration also included for the activation of the Delaware National Guard to assist in hurricane related duties.

[7] Officials began recommending visitors to leave potentially affected areas by three days before Isabel made landfall.

[6] The Delaware Department of Transportation planned to place restrictions on state roads in the event strong wind gusts were recorded.

[8] Strong swells from the hurricane produced a moderate storm surge which peaked at 8.66 feet (2.64 m) in Reedy Point.

[1] Tides were only slightly above normal, though high surf on top of the storm surge resulted in beach erosion,[9] particularly in Sussex County.

[8] The high waters breached dunes south of Bethany Beach, and several locations along Delaware Route 1 were flooded.

The declaration allowed for the use of federal disaster funds and emergency resources to help families and businesses recover from the effects of Hurricane Isabel.

[14] State and federal officials opened a disaster recovery center in Georgetown and Wilmington to assist individuals who suffered losses from Isabel and the remnants of Tropical Storm Henri just days before.

[12] Over 200 volunteers donated time, food and money to provide hot meals for individuals and families affected by the storm.

Support teams provided by county officials transported over 300 tons of ruined accessories from the storm, such as appliances, carpets, and drywall, to local landfills.