2003- Hurricane Isabel

Hurricane Isabel emerged from a tropical wave moving off the African coast on September 1, 2003 but did not gain hurricane status until 7 September. The hurricane then rapidly intensified, moving through Categories 2 and 3 of the Saffir-Simpson Hurricane Wind Scale, and reaching Category 4 status by late on 8 September. Isabel remained at Category 4 strength until reaching Category 5 intensity (the highest category of hurricane strength) on 11 September. After a northwest turn, on 16 September, the system weakened to below major hurricane strength for the first time in 8 days. Although weakening, Isabel’s wind field continued to expand and the storm made landfall as a Category 2 hurricane mid-day on 18 September near Drum Inlet, NC (along the Outer Banks).

High altitude image of Hurricane Isabel's Eye. Source: NASA

Hurricane Isabel was the worst hurricane to affect the Chesapeake Bay region since 1933. It became the costliest (~$3 billion in 2003 USD) and deadliest (17 fatalities) hurricane of 2003. Isabel’s largest effect was due to flood damage, the greatest of which occurred along North Carolina’s Outer Banks. A 1.8-2.4 m (6-8 ft) storm surge caused extensive erosion and overwash near Cape Hatteras, NC, including the destruction of thousands of homes, erosion of protective dunes, and creation of island breaches. The most extensive changes were associated with the opening of a new breach in an island southwest of Cape Hatteras- the breach created a 600 m (2,000 ft) wide inlet, unofficially known as Isabel Inlet.

• Hurricane Isabel was the ninth named storm of the 2003 season, the fifth hurricane, and the second major hurricane.
• The highest wind speed recorded for Hurricane Isabel was 265.5 km/h (165 mph) (Category 5 intensity). The highest observed wind speeds on land were sustained at 127.1 km/h (79 mph) with a gust to 157.7 km/h (98 mph) measured at an instrumented tower near Cape Hatteras, North Carolina on the afternoon of September 18, 2003.
• A NOAA Hurricane Hunter Reconnaissance Aircraft flying into the hurricane launched a dropsonde that measured an instantaneous wind speed of 375 km/h (233 mph), the strongest instantaneous wind speed recorded in an Atlantic hurricane.
• The lowest pressure observed by reconnaissance aircraft was 920 mb on the evening of 12 September. The lowest pressures from official observation sites were 962.8 mb from an instrumented tower in Atlantic Beach, North Carolina on the evening of 18 September, and 963.5 mb at Washington, North Carolina later that night.