29 Jun–2 Jul
27 Aug–8 Sep
30 Aug–2 Sep
25 Sep–7 Oct
T—tropical storm, maximum sustained winds 34–63 kt; H—hurricane, maximum sustained winds 64 kt or higher.
** Dates based on UTC time and include tropical depression stage.
U.S. damage ($ million)
TABLE 1. Atlantic tropical storms and hurricanes of 2003.
Max 1-min wind speed (kt)
Min sea level pressure (mb)
2 4 1
sion, tropical storm, and hurricane stages, but not the extratropical stage. An archive of tropical cyclone re- ports is located on the NHC Internet home page at http://www.nhc.noaa.gov/pastall.shtml. These reports contain the complete best track as well as a detailed description of each storm. The storm summaries in sec- tion 2 below represent abridged versions of the tropical cyclone reports.
near 0000 UTC 21 April with winds of 50 kt (1 kt 0.514791 m s1). This was the peak intensity of the sys- tem. Ana gradually turned toward the east-northeast by 23 April while gradually weakening, and it merged with a cold front on the next day about 810 n mi east of Bermuda.
Ana continued east to east-northeastward as an ex- tratropical low through 26 April and then was aborbed by a frontal system between the Azores and Portugal.
2. Individual tropical storm and hurricane summaries
a. Tropical Storm Ana, 20–24 April
Ana is the first tropical storm on record in April in the North Atlantic basin. The only other tropical or subtropical cyclone known to have occurred in April is a subtropical storm between Puerto Rico and Bermuda from 21 to 24 April 1992.
A nontropical low formed about 210 n mi (1 n mi 1853.248 m) south-southwest of Bermuda on 18 April when an upper-level trough interacted with a frontal system. Moving generally northward, the low produced sporadic bursts of central convection. After turning northwestward, the low looped back toward the south- east on 20 April. The central convection became better organized and the low separated from the frontal sys- tem. It is estimated the low became Subtropical Storm Ana at 0600 UTC 20 April about 215 n mi west of Bermuda.
Satellite microwave wind data showed that a tight inner wind core formed within the nontropical low early on 19 April. However, geostationary infrared sat- ellite imagery showed that the cyclone was still attached to the frontal system at that time. The cylone separated from the front about 24 h later and is estimated to have become subtropical at that time. Ana’s transition to a tropical cyclone is based on data from the Advanced Microwave Sounder Unit on the NOAA polar-orbiting satellites. This sensor indicated that an upper-level warm core formed by late on 20 April, and Ana is estimated to have become tropical by 0000 UTC 21 April. However, experimental cyclone phase diagrams (Hart 2003) suggest that the transition might have oc- curred 6–18 h earlier.
Although Ana did not come close to land, it gener- ated large swells that caused a boat to capsize at Jupiter Inlet, Florida, on 20 April. Two people onboard drowned.
b. Tropical Storm Bill, 29 June–2 July
Based on satellite microwave data showing a warm core, it is estimated that Ana became a tropical storm
Bill made landfall on the Louisiana coast just west of Cocodrie as a tropical storm with 50-kt winds.