Hurricane Danielle was the fourth named storm and the second hurricane of the 1998 Atlantic hurricane season. Danielle was a long-track Cape Verde hurricane that formed on August 24. Danielle took a west-northwest path for a very long time, before turning to the north and northeast, and recurving out to sea. Danielle formed from a tropical wave that exited the coast of Africa on August 21. Danielle was unusual in that it reached its peak intensity of 105 mph four times. Following just days behind Hurricane Bonnie, Danielle remained offshore, fortunately, but it did manage to come close to the United States mainland, very near the same location Bonnie came ashore at earlier in the season. Despite never making landfall, Danielle had a severe impact on the British Isles as an extratropical cyclone on September 6, where it produced significant beach erosion, as well as high seas before merging with another extratropical low near Ireland.
A few people had to be rescued from the treacherous sea conditions produced by the extratropical Danielle, as well as the evacuation of some of the coastal beaches in some locations, including Cornwall. Despite the bad conditions, little damage was reported in the British Isles from Danielle's extratropical remnants. Finally, Danielle did produce tropical storm-force winds on the island of Bermuda while it was still tropical, although no damage was reported on Bermuda, either.
Danielle caused no reported damage, and no fatalities were reported in association with the hurricane.
|Formation||August 24, 1998|
|Dissipation||September 3, 1998|
|Highest winds||105 mph|
|Lowest pressure||960 mbar|
|Areas affected||Eastern Seaboard, Bermuda, northeastern United States, Canadian Maritimes, British Isles|
A tropical wave moved off the coast of Africa on August 21. The wave had an ill-defined circulation cetner amid a cyclonic cloud formation, and deep convection began to form near the center of circulation within 24 hours. Dvorak classifications began on the wave the following day at 1100 UTC. Shortly thereafter, the convective organization of the wave improved, with clusters of showers and cloudiness became more concentrated around the wave's circulation center. On August 24, the wave was classified as Tropical Depression Four while located approximately 600 miles west-southwest of the Cape Verde Islands. The depression continued to strengthen, and as covection began to consolidate itself around the depression's center of circulation, the depression became Tropical Storm Danielle late on August 24. After becoming a tropical storm, Danielle moved west-northwest, strengthening as it did so, due to well-established outflow. On August 25, a pinhole-eye developed within Danielle, and after that, Danielle was upgraded to a hurricane. Danielle was a small storm, with tropical storm-force winds only extending slightly over 100 miles from its center of circulation.
Danielle's small size aided in intensification, and satellite imagery indicated that Danielle continued to intensify as it moved west-northwest, and Danielle reached its first peak intensity of 105 mph while 900 miles east of the Lesser Antilles on August 26. Shortly after reaching its first peak, increasing southwesterly wind shear disrupted Danielle's organization, with reconnaissance aircraft on August 27 stating that Danielle was not well-organized. In spite of a relatively high pressure of 993 mb, Danielle continued to maintain its intensity of 105 mph. The reason for the deviation from the wind-pressure relationship was probably due to Danielle's small size. Significant intensification that Danielle could've undergone continued to be inhibited by moderately strong vertical wind shear, but later on August 27, Danielle again peaked as a 105 mph Category 2 hurricane as measured by reconnaissance aircraft. Some weakening took place over the next few days as Danielle continued to move to the west-northwest. By August 30, Danielle was barely a hurricane, likely because of the cooler water left behind by Hurricane Bonnie.
Danielle continued to move west-northwest as it neared the western periphery of the subtropical ridge on August 30. After that, Danielle's foward speed began to slow down. As Danielle continued to slow down, a movement to the northwest and then to the north began, and Danielle reached its closest approach to the United States mainland on August 31. Upon reaching its third peak as a 105 mph hurricane, Danielle recurved northeast out to sea, due to southwesterly flow ahead of an approaching trough off the East Coast of the United States. On September 1, Danielle briefly reached its fourth and final peak as a 105 mph Category 2 hurricane. After passing 200 miles northwest of Bermuda later on September 1, Danielle began to lose its tropical characteristics while it was located approximately 200 miles south of Cape Race, Newfoundland. Danielle still carried hurricane-force winds at this time, however. On September 4, Danielle became an extratropical cyclone, then moved east to east-northeast across the northern Atlantic Ocean for the next two days, gradually weakening as it did so.
On September 6, Danielle slowed down and turned to the northeast, while located 300 miles west of the British Isles. Danielle lost its identity on September 8 while merging with another extratropical cyclone 200 miles north of Iceland.
The track of Danielle was predicted quite well by both the National Hurricane Center and computer models, and Danielle's recurvature out to sea was predicted in advance. No watches or warnings were issued for the East Coast of the United States, but a Tropical Storm Warning was issued for Bermuda on September 1 as the southern portion of Danielle affected the island.
Danielle off the East Coast of the United States.
Danielle had no notable impact in the United States, since it stayed far away from the United States mainland, even during its closest approach.
Danielle produced winds as high as 35 knots, with gusts as high as 47 knots, while passing 200 miles northwest of Bermuda on September 1. No damage was reported, however, and no fatalities occured.
In the British Isles on September 6, the extratropical remnants of Danielle produced rough sea conditions to the western part of the British Isles. Danielle produced beach erosion in some locations, and many people also had to be rescued from rough sea conditions produced by the extratropical cyclone. Coastal portions of the city of Cornwall were evacuated as high waves broke over the tops of homes. An all-terrain police vehicle was pushed into the sea by a rogue wave in the Isles of Scilly. Fortunately, no deaths or significant damages occured in the British Isles as a result of the then extratropical Danielle.
Lack of Retirement
The name Danielle was not retired in the Spring of 1999 by the World Meteorological Organization, because of the lack of any major damage. It was used again in 2004, and is on the list of names to be used for the 2010 Atlantic hurricane season.