Hurricane Edna - Meteorological History

Meteorological History

Hurricane Edna originated in an easterly tropical wave which modern research has estimated to have spawned a tropical depression east of the Caribbean Sea on September 2, 1954. At the time, a possible surface low pressure area was not noted until several days later, on September 5, while situated between Puerto Rico and The Bahamas. A ship in the vicinity of the disturbance reported heavy squalls and wind gusts to 70 mph (110 km/h). Additionally, the island of Puerto Rico experienced torrential rainfall in association with the storm. Operationally, the system was not recognized to have organized into a tropical cyclone until September 6; it is listed in the Atlantic hurricane database as achieving tropical storm intensity early on September 4. Edna proceeded west-northwestward, bypassing Hispaniola to the north, and by September 7 it had strengthened into a minimal hurricane on the present-day Saffir–Simpson Hurricane Scale.

Initially a rather small storm in terms of physical size, the hurricane steadily intensified throughout the day. Reconnaissance aircraft flew into the storm frequently to take observations on the cyclone's structure. The center of circulation passed near San Salvador Island, and on September 8, Edna further strengthened into a Category 3 major hurricane while broadly curving northward. Reconnaissance flights indicated a maturing and evolving eye, approximately 20 mi (32 km) is diameter. The overall circulation increased in size as banding features became more well-defined. The storm reached its peak winds of 120 mph (190 km/h) and maintained them for over two days. However, reconnaissance data was at times inconsistent and inaccurate, leading to suspicious and unlikely jogs in the storm's track. The cause of these errors is attributed to misinterpretation of radar information.

Midday on September 9, while tracking nearly due north, Edna's minimum central barometric pressure fell to 968 mbar (28.6 inHg), but is believed to have leveled off shortly thereafter. The radius of hurricane-force winds increased, and the storm may have become asymmetrical, with convection concentrated to the right of the center, although this was not confirmed due to a lack of data. Overcast conditions spread over the Eastern Seaboard north of North Carolina in association with the storm and a weak frontal boundary which enhanced the cloudcover. By September 10, Edna was located just south of Cape Hatteras, passing east of the Outer Banks early the next day. As the hurricane accelerated to the northeast, it began to deteriorate and weaken. Closely following the recent track of Hurricane Carol, Edna approached New England, but diverged from Carol's track upon skirting the eastern coast instead of moving inland. Weather reporting stations in the Mid-Atlantic States reported rapid clearing as the storm gained latitude, while heavy rain and gusty winds enveloped New England. On September 11, Edna passed directly over Cape Cod after weakening to Category 1 status, although surface weather analysis depicted a central pressure of 956 mbar (28.2 inHg) or lower. It subsequently tracked just east of Eastport, Maine. The storm continued northeastward into Atlantic Canada and transitioned into an extratropical cyclone, although the exact time of this transition is unknown. The storm's extratropical remnants reemerged into the northern Atlantic after crossing eastern Canada.