Atlantic hurricane season

For the most recent season, see 2012 Atlantic hurricane season.

The Atlantic hurricane season is the period in a year when hurricanes usually form in the Atlantic Ocean. Tropical cyclones in the North Atlantic are called hurricanes, tropical storms, or tropical depressions. In addition, there have been several storms over the years that have not been fully tropical which are categorised as subtropical depressions and subtropical storms.

Worldwide, tropical cyclone activity peaks in late summer, when the difference between temperatures aloft and sea surface temperatures is the greatest. However, each particular basin has its own seasonal patterns. On a worldwide scale, May is the least active month, while September is the most active. We also notice that many of the Atlantic hurricanes occur in the famous Bermuda Triangle. [1] In the Northern Atlantic Ocean, a distinct hurricane season occurs from June 1 to November 30, sharply peaking from late August through September;[1] the season's climatological peak of activity occurs around September 10 each season.[2]

Tropical disturbances that reach tropical storm intensity are named from a pre-determined list. On average, 10.1 named storms occur each season, with an average of 5.9 becoming hurricanes and 2.5 becoming major hurricanes (Category 3 or greater). The most active season was 2005, during which 28 tropical cyclones formed, of which a record 15 became hurricanes. The least active season was the 1914, with only one known tropical cyclone developing during that year.[3] The Atlantic hurricane season is a time when most tropical cyclones are expected to develop across the northern Atlantic Ocean. It is currently defined as the time frame from June 1 through November 30, though in the past the season was defined as a shorter time frame. During the season, regular tropical weather outlooks are issued by the National Hurricane Center, and coordination between the Hydrometeorological Prediction Center and National Hurricane Center occurs for systems which have not formed yet, but could develop during the next three to seven days.

Contents

Concept

The basic concept of a hurricane season began during 1935,[4] when dedicated wire circuits known as hurricane circuits began to be set up along the Gulf and Atlantic coasts,[5] a process completed by 1955.[6] It was originally the time frame when the tropics were monitored routinely for tropical cyclone activity, and was originally defined as from June 15 through October 31.[7] Over the years, the beginning date was shifted back to June 1, while the end date was shifted to November 15,[5] before settling at November 30 by 1965.[8][9] This was when hurricane reconnaissance planes were sent out to fly across the Atlantic and Gulf of Mexico on a routine basis to look for potential tropical cyclones, in the years prior to the continuous weather satellite era.[7] After regular satellite surveillance began, hurricane hunter aircraft flew only into areas which were spotted first by satellite imagery.[10]

Operations

See also: National Hurricane Center and Hydrometeorological Prediction Center

During the hurricane season, the National Hurricane Center routinely issues their Tropical Weather Outlook product, which identifies areas of concern within the tropics which could develop into tropical cyclones. If systems occur outside the defined hurricane season, special Tropical Weather Outlooks will be issued.[11] Routine coordination occurs at 1700 UTC each day between the Hydrometeorological Prediction Center and National Hurricane Center to identify systems for the pressure maps three to seven days into the future within the tropics, and points for existing tropical cyclones six to seven days into the future.[12] Possible tropical cyclones are depicted with a closed isobar, while systems with less certainty to develop are depicted as "spot lows" with no isobar surrounding them.

HURDAT

Main article: HURDAT

The North Atlantic hurricane database, or HURDAT, is the database for all tropical storms and hurricanes for the Atlantic Ocean, Gulf of Mexico and Caribbean Sea, including those that have made landfall in the United States. The original database of six-hourly positions and intensities were put together in the 1960s in support of the Apollo space program to help provide statistical track forecast guidance. In the intervening years, this database — which is now freely and easily accessible on the Internet from the National Hurricane Center's (NHC's) Webpage — has been utilized for a wide variety of uses: climatic change studies, seasonal forecasting, risk assessment for county emergency managers, analysis of potential losses for insurance and business interests, intensity forecasting techniques and verification of official and various model predictions of track and intensity.

HURDAT was not designed with all of these uses in mind when it was first put together and not all of them may be appropriate given its original motivation. HURDAT contains numerous systematic as well as some random errors in the database. Additionally, analysis techniques have changed over the years at NHC as their understanding of tropical cyclones has developed, leading to biases in the historical database. Another difficulty in applying the hurricane database to studies concerned with landfalling events is the lack exact location, time and intensity at hurricane landfall.

Re-analysis Project

Main article: Atlantic hurricane reanalysis

HURDAT has been updated significantly only twice before. The first time was in 2001 when data for years 1851 to 1885 were added to the database. The second time was August 2002 when Hurricane Andrew was upgraded to a Category 5. Recent efforts into uncovering undocumented historical hurricanes in the late 19th and early 20th centuries led by Jose Fernandez-Partagas have greatly increased our knowledge of these past events, which are not yet incorporated into the HURDAT database. Because of all of these issues, a re-analysis of the Atlantic hurricane database is being attempted that will be completed in three years.

In addition to the groundbreaking work by Partagas, additional analyses, digitization and quality control of the data was carried out by researchers at the NOAA Hurricane Research Division funded by the NOAA Office of Global Programs. Over the next two years, this re-analysis will continue to progress through the remainder of the 20th Century.[1] [2]

Over 5000 additions and alterations are now approved for the 1851 to 1910 era by the National Hurricane Center's Best Track Change Committee. (This same process was utilized for the upgrade of 1992's Hurricane Andrew to a Category 5 on the Saffir-Simpson Hurricane Scale last August.) This work on historical hurricanes was originally conducted by the late Jose Fernandez Partagas. Additional analyses, digitization and quality control of the data was carried out by researchers at the NOAA Hurricane Research Division funded by NOAA Office of Global Programs. Over the next two years, this re-analysis will continue to progress through the remainder of the 20th Century.

Official changes to the Atlantic hurricane database are approved by the National Hurricane Center Best Track Change Committee. Thus research conducted by Chris Landsea and colleagues as part of the Atlantic hurricane database reanalysis project likewise goes through this review process. Not all Landsea's recommendations are accepted by the Committee.

Pre-1870

Period Seasons
Pre-19th century Pre-17th century, 17th century, 18th century, 1780
1800–1869 1800-1809, 1810-1819, 1820-1829, 1830-1839, 1840-1849, 1850-1859, 1851, 1852, 1854, 1860, 1861, 1862-1864, 1865, 1866, 1867, 1868, 1869

1800s

1870s

Year Number of
tropical
storms		 Number of
hurricanes		 Number of
major hurricanes		 Deaths Strongest
storm
1870 11 10 2 2,052 Unnamed
1871 8 6 2 30 Unnamed
1872 5 4 0 Unknown Unnamed
1873 5 3 2 626 Unnamed
1874 7 4 0 Unknown Unnamed
1875 6 5 1 800 Unnamed
1876 5 4 2 19 "San Felipe"
1877 8 3 1 34 Unnamed
1878 12 10 1 108 Unnamed
1879 8 6 2 47 Unnamed

1880s

Year Number of
tropical
storms		 Number of
hurricanes		 Number of
major hurricanes		 Deaths Strongest
storm		 Notes
1880 11 9 2 133 Unnamed
1881 7 4 0 700 Unnamed
1882 6 5 2 6 Unnamed
1883 4 3 2 236 Unnamed
1884 4 4 1 8 Unnamed
1885 8 6 1 25 Unnamed
1886 12 10 4 200+ "Indianola" Seven hurricanes struck the United States, the most during a single year[13]
1887 19 11 2 2 Unnamed Tied for third most active season on record
1888 9 6 2 924 Unnamed
1889 9 6 0 40 Unnamed

1890s

Year Number of
tropical
storms		 Number of
hurricanes		 Number of
major hurricanes		 Deaths Strongest
storm		 Notes
1890 4 2 1 9 Unnamed
1891 10 7 1 13 Unnamed
1892 9 5 0 16 Unnamed
1893 12 10 5 4,028 Unnamed Two hurricanes caused more than 2,000 deaths in the United States
Four simultaneous hurricanes on August 22, one of two times on record
1894 7 5 4 200+ Unnamed
1895 6 2 0 56 Unnamed
1896 7 6 2 130 Unnamed
1897 6 3 0 None Unnamed
1898 11 5 1 562 Unnamed
1899 9 5 2 3,439 "San Ciriaco" The San Ciriaco hurricane was the longest lasting Atlantic hurricane on record

1900s

1900-1909

Year Number of
tropical
storms		 Number of
hurricanes		 Number of
major hurricanes		 Deaths Damage
USD		 Strongest
storm		 Notes
1900 7 3 2 8,000+ $60 million "Galveston hurricane" The Galveston hurricane was the deadliest disaster in the United States
1901 12 5 1 10 $1 million Unnamed
1902 5 3 0 None Unknown Unnamed
1903 10 7 1 228 $1.15 million Unnamed
1904 5 3 0 87 $1 million Unnamed
1905 5 1 1 1 Unknown Unnamed
1906 11 6 3 367 $2.48 million Unnamed
1907 5 0 0 None Unknown Unnamed One of two seasons with no recorded hurricanes
1908 10 6 1 None Unknown Unnamed Includes the only known March tropical cyclone in the basin
1909 11 6 4 4,614 $75 million "Grand Isle hurricane"

1910s

Year Number of
tropical
storms		 Number of
hurricanes		 Number of
major hurricanes		 Deaths Damage
USD		 Strongest
storm		 Notes
1910 5 3 1 100 $1.25 million Unnamed
1911 6 3 0 27 $3 million Unnamed
1912 7 4 1 116 $67,000 Unnamed
1913 6 4 0 5 $4 million Unnamed
1914 1 0 0 0 Unknown Unnamed Least active season on record
One of two seasons with no recorded hurricanes
1915 6 5 4 675 $63 million "New Orleans hurricane"
1916 15 10 5 31 $5.9 million Unnamed
1917 4 4 2 5 $170,000 "Nueva Gerona hurricane"
1918 6 4 1 34 $5+ million Unnamed
1919 5 2 1 ~900 $22 million "Florida Keys"

1920s

Year Number of
tropical
storms		 Number of
hurricanes		 Number of
major hurricanes		 Deaths Damage
USD		 Strongest
storm		 Notes
1920 5 4 0 2 $15.75 million Unnamed
1921 7 5 2 6 $36.5 million Unnamed
1922 5 3 1 Unknown Unknown Unnamed
1923 9 4 1 0 Unknown Unnamed
1924 11 5 2 150+ Unknown "Cuba" The 1924 Cuba hurricane was the earliest officially classified Category 5 Atlantic hurricane on the Saffir–Simpson Scale
1925 4 2 0 59+ $19.9 million Unnamed Includes a hurricane that struck Florida on December 1, the latest United States hurricane landfall
1926 11 8 6 1,315+ $1.4+ billion "Great Miami Hurricane"
1927 8 4 1 184 Unknown "Great Gale of August 24"
1928 6 4 1 4,000+ $952.5+ million "Okeechobee hurricane" "Okeechobee hurricane" was the only recorded hurricane to strike Puerto Rico at Category 5 strength
1929 5 3 1 51 $9.0 million Unnamed

1930s

Year Number of
tropical
storms		 Number of
hurricanes		 Number of
major hurricanes		 Deaths Damage
USD		 Strongest
storm		 Notes
1930 3 2 2 8,000 $50 million "Dominican Republic" "Dominican Republic" hurricane was the fifth deadliest hurricane on record
1931 9 2 1 2,502 $7.5 million Unnamed
1932 11 6 4 3,315 $37 million Unnamed
1933 21 10 5 651 $86.6 million Unnamed Second most active season on record
1934 11 6 0 2,017 $4.26 million Unnamed
1935 6 5 3 2,604 $12.5 million "Labor Day hurricane" The 1935 Labor Day hurricane was the most intense United States landfalling tropical cyclone
1936 16 7 1 5 $1.23 million Unnamed Tied for fifth most active season on record
1937 9 3 0 0 Unknown Unnamed
1938 8 3 1 ~700 $290.3 million "Long Island Express"
1939 5 3 1 5 Unknown Unnamed

1940s

Year Number of
tropical storms		 Number of
hurricanes		 Number of
major hurricanes		 Deaths Damage
USD		 Strongest
storm		 Notes
1940 8 4 0 101 $4.7 million Unnamed
1941 6 4 2 63 $10 million Unnamed
1942 10 4 1 17 $30.6 million Unnamed
1943 10 5 2 19 $17.2 million Unnamed First year of Hurricane Hunters
1944 11 7 3 1,153 $202 million "Great Atlantic hurricane"
1945 11 5 3 80 $80 million Unnamed
1946 6 3 1 5 $5.2 million Unnamed
1947 9 5 2 94 $145.3 million "Fort Lauderdale hurricane"
1948 9 6 4 94 $30.9 million Unnamed
1949 13 7 2 3 $58.2 million Unnamed

1950s

Year Number of
tropical storms		 Number of
hurricanes		 Number of
major hurricanes		 Deaths Damage
USD		 Strongest
storm		 Retired names Notes
1950 13 11 8 20 $37 million Dog None Record number of major hurricanes
First year of Atlantic tropical cyclone naming
1951 10 8 5 257 $80 million Easy None
1952 7 6 3 47 $3.75 million Fox None Includes the only known February tropical cyclone in the basin
1953 14 6 4 1 $6 million Carol None First year of female names for storms
1954 11 8 2 1,069 $752 million Hazel Carol, Hazel Includes Alice, one of only two storms in the basin to span two calendar years
1955 12 9 6 1,518 $1.2 billion Janet Connie, Diane, Ione, Janet
1956 9 4 2 76 $67.8 million Betsy None
1957 8 3 2 513 $152.5 million Carrie Audrey
1958 10 7 5 41 $12 million Helene None
1959 11 7 2 59 $23.3 million Gracie Gracie* Status of Gracie's retirement is unclear

1960s

Year Number of
tropical storms		 Number of
hurricanes		 Number of
major hurricanes		 Deaths Damage
USD		 Strongest
storm		 Retired names Notes
1960 7 4 2 385 $410 million Donna Donna
1961 11 8 7 345 $392 million Hattie Carla, Hattie
1962 5 3 1 4 $10 million Ella None
1963 9 7 2 7,225 $589 million Flora Flora Hurricane Flora was the sixth deadliest hurricane on record
1964 12 6 6 261 $605 million Hilda Cleo, Dora, Hilda
1965 6 4 1 76 $1.45 billion Betsy Betsy
1966 11 7 3 1,094 $410 million Inez Inez One named storm de-classified in post-analysis
1967 8 6 1 64 $217 million Beulah Beulah
1968 8 4 0 10 $10 million Gladys Edna The name "Edna" was retired due to the storm in 1954, also includes one subtropical storm
1969 18 12 5 364 $1.7 billion Camille Camille Fourth most active season on record
Tied for second most hurricanes in a season on record
Includes one subtropical storm

1970s

Year Number of
tropical storms		 Number of
hurricanes		 Number of
major hurricanes		 Deaths Damage
USD		 Strongest
storm		 Retired names Notes
1970 10 5 2 71 $454 million Celia Celia
1971 13 6 1 45 $213 million Edith None
1972 7 3 0 122 $2.1 billion Betty Agnes Includes three subtropical storms
1973 8 4 1 15 $18 million Ellen None Includes one subtropical storm
1974 11 4 2 8,260+ $1.97 billion Carmen Carmen, Fifi Includes four subtropical storms
Hurricane Fifi was the fourth deadliest hurricane on record
1975 9 6 3 80 $100 million Gladys Eloise Includes one subtropical storm
1976 10 6 2 72 $100 million Belle None Includes two subtropical storms
1977 6 5 1 10 $10 million Anita Anita
1978 12 5 2 37 $45 million Greta None Includes the January tropical cyclone in the Atlantic
1979 9 5 2 2,118 $4.3 billion David David, Frederic First year for alternating male/female names
Includes one subtropical storm

1980s

Year Number of
tropical cyclones		 Number of
tropical storms		 Number of
hurricanes		 Number of
major hurricanes		 Deaths Damage
USD		 Strongest
storm		 Retired names Notes
1980 15 11 9 2 256 $1 billion Allen Allen
1981 18 12 7 3 10 $45 million Harvey None
1982 9 7 4 1 141 $100 million Debby None Includes one subtropical storm
1983 7 4 3 1 22 $2.6 billion Alicia Alicia
1984 17 13 5 1 35 $66 million Diana None Includes one subtropical storm
1985 13 11 7 3 241 $4.5 billion Gloria Elena, Gloria
1986 10 6 4 0 70 $57 million Earl None
1987 14 7 3 1 10 $73 million Emily None
1988 19 12 5 3 550 $7 billion Gilbert Gilbert, Joan Included strongest hurricane on record until 2005
1989 15 11 7 2 112 $10.7 billion Hugo Hugo

1990s

Year Number of
tropical cyclones		 Number of
tropical storms		 Number of
hurricanes		 Number of
major hurricanes		 Deaths Damage
USD		 Strongest
storm		 Retired names Notes
1990 16 14 8 1 116 $150 million Gustav Diana, Klaus No tropical storms or hurricanes made landfall in the United States
1991 12 8 4 2 30 $2.5 billion Claudette Bob
1992 9 7 4 1 66 $26 billion Andrew Andrew Hurricane Andrew is the second-costliest U.S. hurricane
Includes one subtropical storm
1993 10 8 4 1 274 $271 million Emily None
1994 12 7 3 0 1,184 $1.56 billion Florence None
1995 21 19 11 5 115 $9.3 billion Opal Luis, Marilyn, Opal, Roxanne Tied for third most active season on record
1996 14 14 10 6 179 $3.8 billion Edouard Cesar, Fran, Hortense
1997 9 8 3 1 11 $110 million Erika None Includes one subtropical storm
1998 14 14 10 3 12,000+ $12.2 billion Mitch Georges, Mitch Four simultaneous hurricanes on September 26, the first time since 1893
Hurricane Mitch was the deadliest hurricane in over 200 years
1999 16 12 8 5 465 $5.9 billion Floyd Floyd, Lenny Most Category 4 hurricanes on record

2000s

2000-2009

Year Number of
tropical cyclones		 Number of
tropical storms		 Number of
hurricanes		 Number of
major hurricanes		 Deaths Damage
USD		 Strongest
storm		 Retired names Notes
2000 19 15 8 3 79 $1.2 billion Keith Keith Includes one subtropical storm
2001 17 15 9 4 105 $7.1 billion Michelle Allison, Iris, Michelle Allison is the only Atlantic tropical system to have its name retired without reaching hurricane strength.
2002 14 12 4 2 23 $2.6 billion Isidore Isidore, Lili
2003 21 16 7 3 92 $4.4 billion Isabel Fabian, Isabel, Juan Tied for fifth most active season on record
2004 17 15 9 6 3,100+ $50 billion Ivan Charley, Frances, Ivan, Jeanne Includes one subtropical storm
2005 31 28 15 7 2,280+ $128 billion Wilma Dennis, Katrina, Rita, Stan, Wilma Most active season and costliest on record
Includes one subtropical storm
Tropical Storm Zeta extended into 2006; first such occurrence since 1954
2006 10 10 5 2 14 $500 million Gordon/Helene None
2007 17 15 6 2 423 $3 billion Dean Dean, Felix, Noel Includes one subtropical storm
2008 17 16 8 5 1,047 $42 billion Ike Gustav, Ike, Paloma Tied for fifth most active season on record
Only year on record in which a major hurricane existed in every month from July through November
2009 11 9 3 2 6 $77 million Bill None

2010s

Year Number of
tropical cyclones		 Number of
tropical storms		 Number of
hurricanes		 Number of
major hurricanes		 Deaths Damage
USD		 Strongest
storm		 Retired names Notes
2010 21 19 12 5 259 $12.441 billion Igor Igor, Tomas Tied for third most active season on record
Tied for second most hurricanes in a season on record
Most active season since 2005
2011 20 19 7 3 120 <$11.8 billion Ophelia Tied for third most active season on record
Record for first eight storms unable to become hurricanes

Number of tropical storms and hurricanes per season

This bar chart shows the number of named storms and hurricanes per year from 1893-2011:



See also

Tropical cyclones portal
Weather portal

Parent topics

Atlantic hurricane topics

Other tropical cyclone basins

References

  1. ^ a b Atlantic Oceanographic and Meteorological Laboratory, Hurricane Research Division. "Frequently Asked Questions: When is hurricane season?". NOAA. http://www.aoml.noaa.gov/hrd/tcfaq/G1.html. Retrieved 2006-07-25. 
  2. ^ McAdie, Colin (May 10, 2007). "Tropical Cyclone Climatology". National Hurricane Center. http://www.nhc.noaa.gov/pastprofile.shtml. Retrieved 2007-06-09. 
  3. ^ NOAA (2007). "Atlantic Hurricane Database". NOAA. http://www.aoml.noaa.gov/hrd/hurdat/Data_Storm.html. Retrieved 2009-02-01. 
  4. ^ Associated Press (1941-06-15). "Hurricane Bureau Begins Season's Vigil Tonight". St. Petersburg Times. http://news.google.com/newspapers?id=r8A0AAAAIBAJ&sjid=a00DAAAAIBAJ&pg=7104,1787592&dq=hurricane+season+opened&hl=en. Retrieved 2011-07-09. 
  5. ^ a b Associated Press (1959-06-15). "1959 Hurricane Season Opens Officially Today". Meridian Record. http://news.google.com/newspapers?id=exRIAAAAIBAJ&sjid=owANAAAAIBAJ&pg=1250,4615997&dq=hurricane+season+opened&hl=en. Retrieved 2011-07-09. 
  6. ^ Associated Press (1955-06-15). "Hurricane Season Opens; New England Joins Circuit". The Robesonian. http://news.google.com/newspapers?id=EihAAAAAIBAJ&sjid=vVgMAAAAIBAJ&pg=7094,4148647&dq=hurricane+season+opened&hl=en. Retrieved 2011-07-09. 
  7. ^ a b Associated Press (1960-06-15). "1960 Hurricane Season Open As Planes Prowl". The Evening Independent. http://news.google.com/newspapers?id=0g9QAAAAIBAJ&sjid=dlUDAAAAIBAJ&pg=3556,2273287&dq=hurricane+season+opened&hl=en. Retrieved 2011-07-09. 
  8. ^ Neal Dorst (2010-01-21). "Subject: G1) When is hurricane season ?". National Hurricane Center. http://www.aoml.noaa.gov/hrd/tcfaq/G1.html. Retrieved 2011-07-09. 
  9. ^ Brownsville Herald (1965-06-01). Hurricane Season Officially Opened.
  10. ^ United Press International (1966-05-30). "Hurricane Season Opens This Week". The News and Courier. http://news.google.com/newspapers?id=32FJAAAAIBAJ&sjid=VQoNAAAAIBAJ&pg=684,6978917&dq=hurricane+season+opened&hl=en. Retrieved 2011-07-09. 
  11. ^ National Hurricane Center (2011). "Atlantic Graphical Tropical Weather Outlook". National Oceanic and Atmospheric Administration. http://www.nhc.noaa.gov/gtwo_atl.shtml. Retrieved 2011-07-09. 
  12. ^ United States Department of Commerce (2006). Assessment: Hurricane Katrina, August 23-31, 2005. Retrieved on 2008-09-03.
  13. ^ Hurricane Research Division (2008). "Chronological List of All Hurricanes which Affected the Continental United States: 1851-2007". National Oceanic and Atmospheric Administration. http://www.aoml.noaa.gov/hrd/hurdat/ushurrlist18512007.txt. Retrieved 2008-03-21.