Hurricane Dora was the first tropical cyclone on record to make landfall over the Atlantic coast of North Florida at hurricane intensity. The sixth tropical storm and second hurricane of the 1964 season, Dora developed from a tropical wave near the coast of Senegal on August 28. The depression intensified into Tropical Storm Dora late on August 31. It then curved northwestward and continued to strengthen. By late on September 2, Dora became a Category 1 hurricane. Intensification slowed somewhat, with Dora becoming a Category 2 hurricane on September 4 and then a Category 3 hurricane the following day. Deepening further, the storm briefly peaked as a Category 4 with maximum sustained winds of 130 mph (215 km/h) on September 6. Dora soon weakened to a Category 3 hurricane and then a Category 2 hurricane while curving westward early the following day.
Dora maintained Category 2 intensity over the next few days, except for several hours on September 9. While approaching the northeast coast of Florida, Dora's motion became erratic, making a few cyclonic loops. Early on September 10, the hurricane made landfall near St. Augustine, Florida, with winds of . Dora quickly weakened to tropical storm intensity over land on September 11 and then briefly drifted over southwestern Georgia, until turning northeastward later the next day. Upon merging with a cold front, Dora became extratropical cyclone over coastal South Carolina on September 13. Early on September 14, the extratropical storm emerged into the Atlantic Ocean over the Outer Banks of North Carolina and accelerated, striking Newfoundland on September 15 before being absorbed by another extratropical system.
Along the First Coast of Florida, tides reached up to above mean sea level. Strong winds lashed the region, with sustained wind of observed in St. Augustine. In Jacksonville, approximately 156,000 customers lost power, while about 19% of phones in Duval County were out of service. Much of the damage in the Jacksonville area occurred to older buildings and those located in coastal areas. Additionally, sections of the city experienced wind-induced river flooding in the vicinity of the St. Johns River. Heavy rainfall damaged many unharvested crops and inundated numerous roads and bridges, isolated some communities for several days. Throughout Florida, Dora demolished 74 dwellings and damaged 9,374 others, while 14 mobile homes were destroyed and 218 others suffered severe impact. About 50 farm buildings and 423 small businesses suffered major damage or destruction. Three deaths and at least $230 million in damage occurred. In Georgia, the storm damaged about 1,135 homes and obliterated 5 others. Additionally, 18 trailers suffered major impact, while 43 small businesses were destroyed or experienced severe damage. The state reported one death and at least $9 million in damage. Dora impacted a few other states the East Coast of the United States, but to a much lesser degree. One death occurred in Virginia. Overall, Dora caused $280 million in damage, which is equivalent to $2.6 billion in 2022 USD, and five deaths.
Meteorological history
Hurricane Dora was first identified as a broad area of low pressure on August 28, 1964, that moved off the west coast of Africa into the Atlantic Ocean near Dakar, Senegal. Traveling west-southwestward, the system brushed the Cape Verde Islands on the next day. By August 31, images from the eighth Television Infrared Observation Satellite (TIROS VIII) depicted a developing storm with a central dense overcast, banding features and cirrus outflow. Observations from ship Mormacscan, which passed closest to the storm, indicated decreasing barometric pressures and wind gusts up to . As part of a review of the cyclone during the Atlantic hurricane reanalysis project in 2019, the depression intensified into Tropical Storm Dora around 18:00 UTC on August 31. This was based on an extrapolation of reconnaissance aircraft flight data on September 1, which observed sustained winds of . Shortly thereafter, the Weather Bureau in San Juan, Puerto Rico, issued the first advisory on the storm, with the center estimated to be roughly 850 mi (1,370 km) east of Trinidad.
After advisories began on September 1, Dora turned northwestward and continued to intensify. Several reconnaissance missions into the storm indicated that it attained hurricane status during the afternoon of September 2, which the official Atlantic hurricane database lists as 18:00 UTC. Although contemporary reports indicated that Dora quickly became a major hurricane, the 2019 reanalysis of Dora concluded that remained a Category 1 hurricane on the modern-day Saffir–Simpson hurricane scale until late on September 4 and did not intensify into a Category 3 hurricane until about 24 hours thereafter.
At the time, meteorologists expected the storm to maintain a northwesterly course and be steered over open waters by a trough associated with Hurricane Cleo to the west. However, Dora avoided the trough and instead gradually turned westward September 6. That day, the hurricane attained its peak intensity as a Category 4-equivalent storm with winds estimated at 130 mph (215 km/h) and a minimum atmospheric pressure of . While executing the turn, Dora steadily weakened as its low-level inflow was disrupted, falling to Category 3 intensity around 12:00 UTC on September 6 and then to Category 2 status by early the next day. While initially thought to have re-intensified into a Category 3 hurricane on September 8, the 2019 reanalysis on Dora indicated that the storm remained no stronger than a Category 2 hurricane for the remainder of its duration.
Tracking westward towards Florida, Dora's forward movement decreased and became erratic as it neared the coast. Early on September 9, the storm abruptly turned southeastward before moving north for several hours. Throughout the remainder of the day, Dora executed three distinct cyclonic loops while maintaining a general westward motion. The cyclone weakened to a Category 1 hurricane intensity early on September 9, possibly due to an eyewall replacement cycle, but re-strengthened into a Category 2 hurricane at 18:00 UTC while passing over the Gulf Stream. This resulted in its central pressure decreasing 9 mbar (hPa; ) in a few hours. As Dora neared North Florida in the early hours of September 10, the diameter of its eye decreased from about 28 mi to 8 mi (44 to 13 km). Around 06:00 UTC on September 10, the storm made landfall near St. Augustine, as a strong Category 2 hurricane with sustained winds of 110 mph (175 km/h). Dora became the only hurricane to strike the First Coast region during the 20th century. The cyclone quickly weakened after moving ashore, losing hurricane status within 12 hours, and turned to the north just west of Tallahassee on September 11. Early on the following day, Dora briefly became almost stationary over southwest Georgia, before a cold front caused it to accelerate northeastward. Dora also began merging with the cold front, leading to its transition into an extratropical cyclone over coastal South Carolina around 12:00 UTC on September 13. The extratropical remnants emerged into the Atlantic along the Outer Banks of North Carolina early the following day and continued northeastward, striking Newfoundland late on September 15, shortly before being absorbed by another extratropical system.
Preparations Caribbean Upon Dora's classification on September 1, a small craft advisory was issued for the Leeward Islands and the northern Windward Islands.
United States As Dora approached Florida, gale warnings were issued for the northeast section of the coastline. As Dora moved inland, gale warnings were issued from Sarasota to Pensacola. In addition, small craft for much of the Gulf Coast to the west coast of Florida, and later in the Mid-Atlantic were advised to remain in port until the storm subsided.
Impact Leeward Islands The storm remained far enough from the Leeward Islands to cause little impact. On Saint Kitts, sustained winds reached and gusts peaked at . Additionally, the United States' Weather Bureau office in San Juan, Puerto Rico, noted that "some slight erosion of beaches may have occurred due to heavy surf on September 3 and 4."
United States
Overall, Dora was responsible for five deaths and $280 million in damage in the United States, much of which occurred in Florida. Within Florida and Georgia combined, the hurricane injured nearly 1,500 persons, with 72 of those people requiring hospitalization. Dora demolished at least 79 dwellings, 14 trailers, 2 farm buildings, and destroyed or severely damaged 205 boats and 466 small businesses. Additionally, Dora rendered major damage to at least 492 residences, 236 trailers, and 48 farm buildings, as well as minor damage to 10,017 residences. Approximately 13,476 families in the two states experienced losses relating to the storm.
Florida Along the coast of Florida, tides reached up to above mean sea level. The hurricane also produced storm surge and abnormally high tides on the Gulf Coast of Florida, especially from Tampa Bay to St. Marks, where tides between were observed. Residents were forced to evacuate their homes. Strong winds lashed northeastern Florida, with sustained wind of observed in St. Augustine. Many locations north of Daytona Beach received sustained winds of at least . Because of the slow movement of Dora, some places experienced the worst of the storm for as much as 24 hours. Many areas of North Florida received at least of rainfall, damaging many unharvested crops and inundating numerous roads and bridges, which isolated some communities for several days. Throughout Florida, 74 dwellings were flattened and 9,374 received damage, while 14 mobile homes were destroyed and 218 others suffered severe impact. About 50 farm buildings and 423 small businesses were severely damaged or demolished.
First Coast Jacksonville was one of the most severely impacted cities. Approximately 156,000 customers were left without electricity, while about 19% of phones in Duval County were out of service. The power supply for Jacksonville and surrounding towns was lost for six days. Much of the damage in the Jacksonville area occurred to older buildings and those located in coastal areas. Additionally, sections of the city experienced wind-induced river flooding in the vicinity of the St. Johns River. Along the coast, Atlantic Beach and Jacksonville Beach were lashed by storm surge, which flooded low-lying areas and swept away houses and roads. One street in the latter was inundated with about of water. Three homes were destroyed and 3,992 suffered damage, while 5 mobile homes were demolished and 25 experienced impact, overall in Duval County.
The storm was also one of the factors that nearly led to the cancellation of a Beatles concert at Gator Bowl Stadium in Jacksonville on September 11; other reasons included that the Beatles would not perform with a segregated audience, the American Guild of Variety Artists forced the Fab Four to pay union dues, and that a group of filmmakers attempted to create bootleg footage of the concert. Those issues were eventually resolved. Initially, the Beatles planned to fly to Jacksonville after their concert in Montreal on September 8, but the storm forced their plane to be diverted to Key West. Just hours before the concert began, the Beatles arrived at Imeson Field. More than 20,000 fans attended the concert, though thousands of others could not attend due to power outages in the city. Because winds were still gusting up to , Ringo Starr's drums were nailed to the stage.