Hurricane Felix was the sixth named storm, second hurricane, and second major hurricane of the 2001 Atlantic hurricane season. Felix formed on September 7 from a tropical wave. The depression that spawned Felix degenerated into a tropical wave on September 8. By September 10, it regenerated, strengthened into a tropical storm, then to a hurricane as it moved northeast and out to sea. Felix peaked as a 115 mph Category 3 hurricane on the Saffir-Simpson Hurricane Scale with a pressure of 962 mb. Felix dissipated on September 19.
Felix caused no damage and no deaths.
|Formation||September 7, 2001|
|Dissipation||September 19, 2001|
|Highest winds||115 mph|
|Lowest pressure||962 mbar|
A tropical wave moved off the coast of Africa on September 5, accompanied by a surface low. The wave moved westward for the next two days. On September 6, QuikSCAT indicated that the surface circulation near the wave axis has become better-defined. Deep convection began to increase and weak banding features developed within the wave tracked a few hundred miles south of the Cape Verde Islands. By early on September 7, QuikSCAT data and nearby ship observations indicated that the wave had become better-defined, with 10 to 15 knot westerly winds about 120 miles southwest of the low-level circulation center. Deep convection became more organized around the center, and the banding features continued to improve, as evidenced by visible satellite imagery. Based on Dvorak classifications that day, it is estimated that Tropical Depression Seven formed from this wave at 1200 UTC on September 7, while located about 360 miles southwest of the Cape Verde Islands. After forming, the depression moved rapidly westward at a foward speed of 18 to 20 knots for the next day or so. In spite of favorable upper-level ridging across the depression, the depression failed to organize any further. It is theorized that the depression's rapid westward movement may have contributed to some wind shear at the lower levels, which resulted in the deep convection becoming displaced further east of the low-level circulation center. Another possibility, based on satellite water vapor and AMSU (Advanced Microwave Sounding Unit) temperature data, is that the surrounding environment was more stable than usual, which could also have been an inhibiting factor to maintaining persistent deep convection near the center.
By 1800 UTC on September 8, the convection became disorganized and QuikSCAT data, along with ship reports, indicated that the depression had degenerated into a tropical wave while located about 650 miles southwest of the Cape Verde Islands. The wave moved westward at a foward speed of 15 knots for the next 36 hours. An unfavorable vertical shear pattern developed across the system when an upper-level trough amplified southward into the deep tropics to the west of the wave. Despite this, the southwesterly shear eventually abated enough to allow convection to refire near the mid-level circulation center of the wave late on September 9. By 0600 UTC on September 10, the wave acquired a closed surface circulation once again, based on conventional satellite imagery. Based on this, the wave was upgraded once again to a tropical depression. A QuikSCAT pass at 0816 UTC confirmed the existance of a broad cyclonic circulation within the surface wind field. The depression tracked to the west-northwest, and it became Tropical Storm Felix at 1200 UTC on September 11. Felix moved northwest and slowly intensified as it did so. Around 0000 UTC on September 13, Felix became a hurricane.
Felix rapidly intensified, its winds increasing 35 mph in an 18-hour period. It is estimated that Felix reached its peak intensity around 0000 UTC on September 14 as a 115 mph Category 3 hurricane with a pressure of 962 mb. At this time, Felix was located about 1400 miles southwest of the Azores. Felix maintained major hurricane status until 0600 UTC, after which time Felix began to move northeast and then gradually turn eastward in advance of an approaching mid-latitude trough. Shortly after peaking, Felix began to weaken because of increased westerly wind shear. Late on September 16, Felix began to turn northeast and began to weaken over much cooler waters. By 1200 UTC on September 17, Felix weakened to a tropical storm. At this point, Felix stalled about 350 miles southwest of the Azores. Increasing northwesterly wind shear as well as upwelling caused Felix to weaken rapidly as it drifted to the south over its cold wake. By 1800 UTC on September 18, Felix weakened to a tropical depression and by 1900 UTC on September 19, Felix dissipated, while located about 400 miles southwest of the Azores.
Lack of Retirement
Because Felix did not affect any land areas, it was not retired in the Spring of 2002 by the World Meteorological Organization. It was used again during the 2007 Atlantic hurricane season.