The North Atlantic Hurricane Season 2005


The record-setting 2005 hurricane season officially comes to a close on Wednesday. Tropical Storm Delta is making sure it ends with a bang. Delta, the 25th named storm of the season, is a strong tropical storm, with sustained winds just below hurricane status. The system is currently undergoing shear from an approaching front. This front will weaken the tropical storm and eventually the two systems will merge. Look for Delta to be classified as extratropical on Monday. No other tropical systems are looming in the Atlantic or eastern Pacific basins.

The 2005 Atlantic hurricane season already has shattered many long-standing records, chief among them a record number of named storms (25) breaking the record from 1933 with 21 storms, requiring the use of the Greek alphabet for the last four storms. There have also been (13) hurricanes so far this season breaking the old record of 12 set in 1969. Another record set was for the most category five hurricanes (3) in a season with Katrina, Rita, and Wilma. Wilma would become the strongest hurricane on record in the Atlantic Basin with a pressure of 882 mb breaking the old record held by Gilbert set in 1988 with a pressure of 888 mb. Katrina will likely be the costliest U.S. hurricane on record. Also, the final tally for damage will go on to show that this season was the most costly in U.S. History breaking the terrible season of 2004 with 45 billion in damage just recently set last year. The landfall of (4) major hurricanes on the U.S. set a record.

November named storms haven't been a stranger to the Atlantic Basin, however. Last year, Tropical Storm Otto flared in the open Atlantic Ocean the last day of November. A pair of tropical storms, Odette and Peter, spun up in early December 2003. U.S. hurricane landfalls in November, thankfully, are very rare. Since 1861, only four U.S. November hurricane landfalls have occurred, most recently 20 years ago when Category Two Hurricane Kate struck near Apalachicola, Fla. This was the only November U. S. hurricane landfall in the last 70 years.

Overview of the 2005 hurricane season:

The 2005 season began early with Tropical Storm Arlene forming on June 9th from a tropical depression in the southwest Caribbean Sea. Tropical Storm Bret also formed in June making it only the 13th time since 1851 that 2 tropical storms are known to have formed in June.

A record active July followed, wherein 5 named storms (Cindy, Dennis, Emily, Franklin and Gert) formed. The previous record for the number of named storms in July was four. Of the 5 named storms, 2 major hurrianes formed tying a record set in 1916. The seven named storms that had formed up until the end of July represented a record level of activity for the first two months of the season.

A further five named storms formed in August of which two were hurricanes bringing the seasonal total to 12 named storms and 4 hurricanes - well above the long term average as of August 31st, which is 4.4 storms and 2.1 hurricanes. August also saw the development of Hurricane Katrina, which will likely be one of the most costly and destructive storms in US history. At one stage a category 5 hurricane, Katrina ultimately made landfall in Louisiana and Mississippi at category 4 strength. While loss of life will not approach the magnitude of the Galveston Hurricane of 1900 (6000-12000 deaths), it nonetheless caused approximately 1,000 deaths and will likely cost more than 100 billion dollars - by far the highest cost of any hurricane in history.

In September, five hurricanes formed leading to a seasonal total nearly double the June-September average number of named storms. In only one other year (1933) had this many storms (17) formed by the end of September. The 2005 season eventually surpassed 1933 for the number of named tropical cyclones. The second category five hurricane of the season developed in September - Hurricane Rita. Impacting the Florida Keys and eventually the Texas/Louisiana border, it prompted massive evacuations along the Gulf Coast and caused widespread damage in parts of Southwest Louisiana, just weeks after Katrina impacted the state. Hurricane Ophelia also impacted the US as it raked the North Carolina coast leading to 10-12 inches of rain for coastal areas as well as significant coastal erosion.

October produced some unusual tropical activity and the most intense Atlantic hurricane on record. Six named storms formed during the month leading to an extension of the naming system to include the Greek alphabet. Hurricane Wilma entered the record books in October as having the lowest central pressure of any Atlantic hurricane at 882 mb, beating Hurricane Gilbert in 1988 with 888 mb. At one stage a category 5 storm, Wilma produced well over 60 inches of rain as it moved across the Yucatan Peninsula, then turned northeastward and eventually made landfall in Florida as a category 3 storm. Hurricane Vince was unusual in its track and location. Vince became a hurricane in the eastern Atlantic and tracked northeastward, passing northwest of the Madeira Islands. Weakening, it eventually made landfall in Spain as a tropical depression. It is the first known instance of a tropical cyclone making landfall in Spain. Tammy impacted northeast Florida as a tropical storm and Tropical Storm Alpha and Hurricane Beta also formed in October. For the first time since the naming convention was instituted, the Greek alphabet had to be employed as the 22nd named storm of the season developed. Alpha produced heavy rains across portions of Hispaniola, while Beta became a major (category 3) hurricane as it neared the coast of Nicaragua, eventually making landfall at category 2.

So far in November it has been active with two named storms Tropical Storm Gamma and Tropical Storm Delta. These two storms have added to the record setting season of 2005 with 25 named storms. This total by far exceeds the record of 21 named storms set in 1933. It also extends the use of the Greek alphabet to the fourth letter well beyond the designated regular alphabet. Tropical Storm Gamma formed in the Caribbean and moved across and impacted northern Honduras and Belize with flooding rains before being sheared by strong westerly winds. Tropical Storm Delta formed well out in the central Atlantic with only impacts for shipping interests.