Earl (2010)

A strong tropical wave that moved off the west coast of Africa on 23 August became Tropical Depression Seven on 25 August about 200 nautical miles west-southwest of the Cape Verde Islands. The system strengthened to Tropical Storm Earl that day and moved generally west to west-northwest under a subtropical ridge. Earl became a hurricane by 29 August east of the northern Leeward Islands, underwent rapid intensification around 30 August, weakened briefly, then re-intensified to a major hurricane and followed a northward turn along the western Atlantic before accelerating toward Atlantic Canada. It became extratropical in the Gulf of St. Lawrence on 5 September and merged with another low over the Labrador Sea on 6 September.

Earl made two landfalls in Canada on 4 September. It struck near Liverpool, Nova Scotia, around 1500 UTC as a hurricane with 65-kt (approximately 75 mph) 1-minute sustained winds. About four hours later, Earl moved over Prince Edward Island around 1900 UTC as a tropical storm with about 60-kt (approximately 70 mph) sustained winds.

The storm’s maximum analyzed intensity was 125 kt (about 145 mph) at 0600 UTC 2 September, with a minimum central pressure of 927 mb. At that time Earl was a Category 4 hurricane on the Saffir–Simpson scale while centered roughly 380 nautical miles southeast of Wilmington, North Carolina.

Storm surge and rainfall were significant in several areas. The highest reported surge was 4.27 ft at Hatteras Village, North Carolina; surges up to about 3 ft occurred along much of the U.S. East Coast from North Carolina through Maine. In Maine, reported storm-tide values were as high as about 19 ft at Eastport (dominated by tide). Rainfall totals included nearly 8 inches on Antigua, 3–5 inches across the northern Leeward Islands, and common totals of 3–5 inches in far eastern North Carolina, southeastern Massachusetts, and much of eastern Maine. Selected station reports included 7.75 inches at Antigua (TAPA) and rainfall of 12.05 inches storm tide/ rain reference values noted at Bar Harbor, Maine (storm tide and coastal tide effects were large there).

Five deaths were associated with Earl: two men drowned offshore of New Jersey (rough surf), a 7‑year‑old girl was swept out to sea at Acadia National Park in Maine, a 14‑year‑old girl died from high surf in northeastern Florida, and a 54‑year‑old man drowned in Blind Bay, Nova Scotia. Damage was concentrated in the northern Leeward Islands (Antigua and Barbuda reported about $12.5 million damage) and along parts of the U.S. East Coast; total estimated damage from Earl is about $45 million, roughly $18 million of that in the United States. Coastal flooding, beach erosion, downed trees, and power outages were reported in New England and Atlantic Canada.

Noteworthy aspects include Earl’s Cape Verde origin and its rapid intensification to a Category 4 hurricane over the open Atlantic, observed concentric eyewall cycles that affected strength, and good forecast performance overall: NHC track and intensity errors were generally below the recent five‑year means and the storm’s genesis was well anticipated more than a day in advance.