Hurricane Dorian Makes Landfall at Cape Hatteras, Threatens Canadian Maritimes

Hurricane Dorian made an official landfall at Cape Hatteras, North Carolina on Friday morning and posed a serious threat to the Canadian Maritime provinces.  At 5:00 p.m. EDT on Friday the center of Hurricane Dorian was located at latitude 36.9°N and longitude 72.7°W which put it about 330 miles (530 km) south-southwest of Nantucket, Massachusetts.  Dorian was moving toward the northeast at 24 m.p.h. (39 km/h).  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 105 m.p.h. (165 km/h).  The minimum surace pressure was 958 mb.

A Tropical Storm Warning was in effect for the portion of the coast from the North Carolina/Virginia border to Fenwick Island, Delaware, and for Chesapeake Bay south of Drum Point.  A Tropical Storm Warning was in effect for the portion of the coast from Woods Hole to Sagamore Beach, Massachusetts including Martha’s Vineyard and Nantucket.  A Tropical Storm Warning was in effect for the portion of the coast from Bar Harbor to Eastport, Maine.  A Hurricane Warning was in effect from Hubbards to Avonport, Nova Scotia.  A Hurricane Watch was issued for Prince Edward Island, Avonport to Hubbards, Nova Scotia, the Magdalen Islands, Parson’s Pond to Indian Harbour, Newfoundland.  Tropical Storm Warnings were issued for Prince Edward Island and from Avonport to Hubbards, Nova Scotia.  A Tropical Storm Watch was in effect for New Brunswick from Fundy National Park to Shediac.  A Tropical Storm Watch was issued for Newfoundland from Francois to Boat Harbor.  A Tropical Storm Watch was  issued for the portion of the coast from Parson’s Pond to Triton, and from Indian Harbour to Stone’s Cove, Newfoundland.

The National Hurricane Center determined that the center of Hurricane Dorian passed over Cape Hatteras and identified that as the point of landfall.  Hurricane Dorian has been moving rapidly away from the coast since that time.  Hurricane Dorian remained a large, well organized hurricane.  A circular eye with a diameter of 35 miles (55 km) was apparent on satellite images.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Winds to hurricane force extended out about 80 miles (130 km) from the center of circulation.  Winds to tropical storm force extended out about 230 miles (370 km) from the center.  The Hurricane Intensity Index (HII) for Hurricane Dorian was 13.9.  The Hurricane Size Index (HSI) was 23.3 and the Hurricane Wind Intensity Size Index (HWISI) was 43.2.

Hurricane Dorian will move through an environment favorable for intensification on Saturday.  Dorian will start out over water where the Sea Surface Temperature is near 27°C.  Dorian will move over cooler water later on Saturday.  An upper level trough over the eastern U.S. will contribute to upper level divergence, which may pump out enough mass to allow the surface pressure to decrease.  Hurricane Dorian will start to make a transition to an extratropical cyclone later on Saturday.  The interaction of colder and warmer air could also provide additional energy to the transitioning hurricane.  There is a chance that Hurricane Dorian could strengthen to a Category 2 hurricane on the Saffir-Simpson Scale on Saturday.

The upper level trough over the eastern U.S. will steer Hurricane Dorian rapidly toward the northeast during the weekend.  On its anticipated track, Dorian will pass southeast of Massachusetts on Saturday morning.  Hurricane Dorian could reach Nova Scotia by Saturday afternoon.  Dorian could be one of the strongest hurricanes to affect the Canadian Maritime provinces.  It will be capable of causing widespread serious damage.