Hurricane Diana (1984) - Meteorological History

Meteorological History

The origins of Hurricane Diana can be traced back to a stalled out area of low pressure just north of the Bahamas along the tail end of a cold front on September 6. Shower and thunderstorm activity began to increase the next day but was generally disorganized. Around 1200 UTC on September 8, a ship in the vicinity of the low reported a sustained wind speed of 40 mph (65 km/h). A few hours later, based on satellite observations, the low was designated Tropical Storm Diana. With weak steering currents, Diana gradually intensified as it slowly moved towards the west over the next day, coming within 50 miles (85 km) of Cape Canaveral, Florida, before taking a sharp turn towards the north-northwest. As Diana neared Saint Augustine, Florida, it turned towards the northeast and intensified into a hurricane.

Under weak steering currents while detached to the front, Diana drifted westward, and came within 50 miles (80 km) of the Florida coast. Rather than continuing westward, where it would have hit near Cape Canaveral, Diana turned to the northwest where it paralleled the coastline. The storm, continually strengthening over the Gulf Stream, turned to the northeast and became a hurricane on September 10. On September 11 and September 12, Diana rapidly intensified to a peak of 130 miles per hour (210 km/h) winds while remaining offshore.

An approaching frontal system caused Diana to execute a cyclonic loop, where cool, dry air caused it to weaken. The hurricane hit Wilmington, North Carolina as a weakening hurricane with maximum sustained winds of 90 miles per hour (140 km/h) on September 13, and quickly weakened to a tropical storm over land. The high pressure system that built in after Diana looped weakened, allowing the storm to move to the north and east. After crossing the Outer Banks, Diana accelerated to the northeast, and after restrengthening to a 70 miles per hour (110 km/h) storm, became extratropical near Nova Scotia on September 16.