Answers to Questions about Hurricanes



The how, what, where, when, and why of hurricanes and tropical weather


  • What is the definition of a tropical depression, tropical storm, and hurricane?

    • Tropical Depression - A tropical cyclone in which the maximum sustained surface wind speed is 38 mph or less.
    Tropical Storm - A tropical cyclone in which the maximum sustained surface wind speed ranges from 39 mph to 73 mph.
    Hurricane - A tropical cyclone in which the maximum sustained surface wind is 74 mph or more.

  • What is the definition of a tropical cyclone, subtropical cyclone, extratropical cyclone and potential tropical cyclone?


    • Tropical Cyclone
    A warm-core non-frontal synoptic-scale cyclone, originating over tropical or subtropical waters, with organized deep convection and a closed surface wind circulation about a well-defined center. Once formed, a tropical cyclone is maintained by using heat energy from the ocean. In this they differ from extratropical cyclones, which derive their energy from horizontal temperature contrasts in the atmosphere (baroclinic effects).


    Extratropical Cyclone
    A term used in advisories and tropical summaries to indicate that a cyclone has lost its "tropical" characteristics. The term implies both poleward displacement of the cyclone and the conversion of the cyclone's primary energy source from the release of latent heat of condensation to baroclinic (the temperature contrast between warm and cold air masses) processes. It is important to note that cyclones can become extratropical and still retain winds of hurricane or tropical storm force.


    Subtropical Storm
    A subtropical cyclone in which the maximum sustained surface wind speed is 39 mph or more.


    Potential Tropical Cyclone
    This is a designation for a tropical disturbance that has a strong possiblity of becoming a tropical cyclone. This definition was introduced in 2017 to allow the National Hurricane Center to issue advisories before a tropical cyclone actually formed. This would give additional lead time for prepartions to be commenced at locations that may be affected.

  • How do you forecast hurricanes?

    • Click here for more details.

  • What is the difference between a hurricane and a typhoon?

    • A hurricane and typhoon are the same. They are simply tropical cyclones that form in different parts of the world. The term hurricane is used in the north Atlantic ocean, the north Pacific (east of the dateline) and the south Pacific (east of 160E). The term typhoon is used in the northwest Pacific ocean (west of 160E) and southeast Indian Ocean (east of 90E). In addition to the names "hurricane" and "typhoon", severe tropical cyclone is used in the southwest Pacific ocean (west of 160E) and southeast Indian Ocean (east of 90E).
    Tropical cyclone is the name used in the southwest Indian Ocean and severe tropical cyclone is used in the southwest Indian Ocean.

  • When is hurricane season?

    • Click here for more information. Check bottom of article.

  • How are hurricanes named?

    • 1950-1952 In the North Atlantic, the naming of tropical cyclones officially started in 1950. For the first two years tropical cyclones were given names based on the phonetic alphabet. (A - able, B - Baker, C - Charlie, D - Dog and so on)
    1953-1978 Starting in 1953 the U.S. Weather Bureau changed from the phonetic alphabet to women's names. They came up with six different lists of names to be rotated, one list each year.
    1979-now In 1979 the World Meteorological Organization and the National Weather Service decided to add men's names to the lists. Women's and men's names are rotated on the lists.

  • Why are some hurricane names not used any longer?

    • When a hurricane causes great damage or cost the name is retired. The World Meteorological Organization votes on a replacement name.

  • What is the difference between a hurricane watch and a hurricane warning?


    • Hurricane Watch - An announcement that sustained winds of 64 knots (74 mph or 119 km/hr) or higher are possible within the specified area in association with a tropical, subtropical, or post-tropical cyclone. Because hurricane preparedness activities become difficult once winds reach tropical storm force, the hurricane watch is issued 48 hours in advance of the anticipated onset of tropical storm force winds.


    Hurricane Warning - An announcement that sustained winds of 64 knots (74 mph or 119 km/hr) or higher are expected somewhere within the specified area in association with a tropical, subtropical, or post-tropical cyclone. Because hurricane preparedness activities become difficult once winds reach tropical storm force, the warning is issued 36 hours in advance of the anticipated onset of tropical-storm-force winds. The warning can remain in effect when dangerously high water or a combination of dangerously high water and waves continue, even though winds may be less than hurricane force.



  • What can you do to prepare for a hurricane?

    • Check our hurricane preparedness page for more information.

  • Where do hurricanes occur in the world?

    • Hurricanes can form in the tropical or subtropical oceans around the whole world. Tropical cyclones can form in any part of the world where the right conditions exist for them to develop. The Atlantic, Pacific, and Indian Oceans have the right conditions for tropical cyclones to develop. Click here for more information.

  • What are the different effects of a hurricane?

    • 1. Storm Surge - This is the water that is "piled up" ahead of a hurricane because of the strong winds blowing over the ocean. The low pressure has a very minimal effect on storm surge. The surge is what inudates coastal areas with flooding.
    2. Tornadoes - They are usually found in spiral bands in the right front quadrant relative to motion.
    3. Wind Damage - The strongest winds are found in the eyewall of a hurricane. Squalls are also found in the spirial bands. Winds can gust to more than 200 mph in the strongest hurricanes.
    4. Inland Flooding - This is not flooding caused by surge, but by heavy rainfall. This is especially true with slow moving tropical cyclones.

  • Who are the Hurricane Hunters?

    • They are the men and women of the the 53rd Weather Reconnaissance Squadron of the Air Force Reserve, based at Keesler Air Force Base in Biloxi, Mississippi.
    They fly into tropical cyclones to send important hurricane information to the National Hurricane Center. Information such as temperature, barometric pressure, wind speed and direction are measured.

  • Does Global Warming affect hurricanes?

    • Read more about global warmings effect on hurricanes.

  • How do hurricanes form?

    • Article on how hurricanes form.

  • What causes hurricanes?

    • Here is more information on the causes of hurricanes.

  • What causes typhoons?

    • Click here for more about the causes for typhoons.

  • Could a category 5 hurricane hit New York City?

    • Read the article here.

The Structure of Hurricanes

  • What are the different parts that make up a hurricane?

    • There are number of basic parts to a hurricane.

    1. Eye - The most notable part of a hurricane. The eye is located at the center of a hurricane. It is where winds are sinking and calm or nearly calm. Air pressure is at its lowest in the eye. Skies are usually fair with only a few clouds. Sometimes high cirrus clouds obscure the eye so that it is not visible on satellite pictures. The eye is usually circular, but can be elliptical too.

    2. Eye Wall - This is the ring of the strongest winds and heaviest rainfall surrounding the eye.

    3. CDO or Central Dense Overcast - A nearly circular region of the hurricane that contains steady heavy rainfall and strong winds.

    4. Spiral Bands - Curved lines of squalls reaching out from the hurricane that have brief gusty winds and downpours.

  • Where are the strongest winds found in a hurricane?

    • The strongest winds in a hurricane are found in the eyewall which surrounds the eye. Also, the strongest winds in the eyewall are several thousand feet above the ground above the effects of friction.

  • How big are hurricanes?

    • Hurricanes can very greatly in size. One measurement of hurricane size is how far the gale force winds (39-54 mph - NWS definition) extend from the center. Typhoon Tip which occured in the Pacific Ocean in 1979 had gale force winds extend out 1380 miles! On the other extreme, Tropical Storm Marco (2008) in the Bay of Campeche had tropical storm force winds extend out only 11.5 miles! On average, hurricanes are 300-400 miles in diameter.

  • Largest Atlantic Hurricanes

    • Hurricane Size by Gale Winds
    Rank Hurricane Name Year Size
    1 Sandy 2012 945 miles
    2 Igor 2010 865 miles
    3 Nicole 2016 815 miles


  • How big is the eye of a hurricane?

    • The eye of a hurricane varies greatly in diameter. On average, the eye is about 20 miles wide. The smallest eye ever measured was Hurricane Wilma, also the hurricane with the lowest pressure on record in the Atlantic basin. Wilma's eye had a diameter of just 2.3 miles. The eye can be very large too. Typhoon Carmen (1960) in the northwestern Pacific had and eye that was 230 miles in diameter!

  • Do tornadoes form in hurricanes?

    • Tornadoes do form in hurricanes. They are most likely to be found in the right front quadrant of a hurricane relative to storm motion. Tornadoes usually are found in the spiral bands during landfall. The reason for this is that the vertical wind shear increases during landfall which is favorable for tornado formation.

  • Hurricanes that produced the most tornadoes

    • Keep in mind that more unrecorded tornadoes may have occured with earlier tropical cyclones

    Most tornadoes in a hurricane (30 or more)
    Rank Hurricane Name Year Tornadoes
    1 Ivan 2004 117
    2 Beulah 1967 115
    3 Frances 2004 103
    4 Rita 2005 98
    5 Katrina 2005 59
    6 TS Fay 2008 50
    7 Gustav 2008 49
    8 Cindy 2005 48
    9 Georges 1998 47
    10 TS Lee 2011 46
    11 Danny 1985 39
    12 TS Beryl 1994 37
    13 David 1979 34
    14 Ike 2009 33


  • How long do hurricanes last?

    • A hurricane ususally lasts several days. It can vary from just one day to in some rare cases last three to four weeks. Any one location can be affected by a hurricane for hours or a couple of days if it happens to stall over a location.

  • What determines the direction that hurricanes move?

    • The direction is determined by the average wind motion over a large area. Hurricanes clouds billow up to the top of the troposphere. Many times wind direction changes with height as well as over the distance of the hurricane. If the wind direction changes with height the hurricane can be sheared or torn into different directions. In this case the low level circulation may continue in one direction where the deep thunderstorm clouds move into another direction.

  • Is it possible to drop a bomb and destroy a hurricane?

    • No chance. The amount of energy that a hurricane contains dwarfs even the largest bombs known.

Hurricane Records and Numbers

  • What was the greatest number of hurricanes to occur at one time?

    • The most hurricanes at one time in the Atlantic was four. It has occured twice, the first time in 1893. The second occurrence was September 25, 1998. The hurricane names were Georges, Ivan, Jeanne and Karl.

  • What is the average number of named storms in the Atlantic each year?

    • The average number of named storms in the Atlantic is 14.

  • What is the record number of named storms in the Atlantic? (including subtropical)

    • 30 in the year 2020. There was 28 in 2005, 20 in 1933 and 2023, and 19 in 1887, 1995, 2010, 2011, 2012

  • What is the average number of hurricanes in the Atlantic each year?

    • The average number of hurricanes in the Atlantic basin is 7 of which 3 become major hurricanes.

  • What is the average number of hurricanes in the world each year?

    • The long term average number of named storms is 84 globally of which 45 develop in hurricanes (or equivalent tropical cyclone).

  • What was the least number of Atlantic hurricanes on record in one year?

    • There were no hurricanes reported in the years 1907 and 1914.

  • What was the greatest number of Atlantic hurricanes on record in one year?

    • There were 15 hurricanes in the Atlantic basin in the year 2005. 1969 and 2010 were second with 12 hurricanes.

  • What was the greatest number of major Atlantic hurricanes on record in one year?

    • There were 8 in 1950, 7 in 2005, and 6 in the years 1926, 1955, 1961, 1964, 1996, 1999.

    The Deadliest, Costliest and Most Intense Hurricanes

  • What were the strongest Atlantic hurricanes in terms of windspeed?

    • Atlantic Category 5 Hurricanes
    Rank Hurricane Name Year Top Sustained Winds
    1 Allen 1980 190 mph
    2 Dorian 2019 185 mph
    2 Wlima 2005 185 mph
    2 Gilbert 1998 185 mph
    2 "Keys Labor Day" 1935 185 mph
    6 Milton 2024 180 mph
    6 Irma 2017 180 mph
    6 Rita 2005 180 mph
    6 Mitch 1998 180 mph
    10 Maria 2017 175 mph
    10 Felix 2007 175 mph
    10 Dean 2007 175 mph
    10 Katrina 2005 175 mph
    10 Andrew 1992 175 mph
    10 David 1979 175 mph
    10 Anita 1977 175 mph
    10 Camille 1969 175 mph
    10 Carla 1961 175 mph
    10 Janet 1955 175 mph
    10 "Cuba" 1932 175 mph
    21 Ivan 2004 165 mph
    21 Isabel 2003 165 mph
    21 "Cuba" 1924 165 mph
    24 Michael 2018 160 mph
    24 Matthew 2016 160 mph
    24 Emily 2005 160 mph
    24 Hugo 1989 160 mph
    24 Edith 1971 160 mph
    24 Beulah 1967 160 mph
    24 Hattie 1961 160 mph
    24 Donna 1960 160 mph
    24 Ethel 1960 160 mph
    24 Cleo 1958 160 mph
    24 Carol 1953 160 mph
    24 "Long Island Express" 1938 160 mph
    24 "Tampico" 1933 160 mph
    24 "Cuba - Brownsville" 1933 160 mph
    24 Bahamas 1932 160 mph
    24 "San Felipe 2 - Okeechobee" 1924 160 mph


  • What were the most intense hurricanes on record in the Atlantic in terms of pressure?
    • The Most Intense Atlantic Hurricanes
    Rank Hurricane Name Year Category Pressure
    1 Wilma 2005 5 882 mb
    2 Gilbert 1988 5 888 mb
    3 "Keys Labor Day" 1935 5 892 mb
    4 Rita 2005 5 895 mb
    5 Milton 2024 5 897 mb
    6 Allen 1980 5 899 mb
    7 Camille 1969 5 900 mb
    8 Katrina 2005 5 902 mb
    9 Mitch 1998 5 905 mb
    9 Dean 2007 5 905 mb


  • What were the most intense hurricanes on record to hit the U.S.?

    • Most Intense U.S. Hurricanes at Landfall* (pressure)
    Rank Hurricane Name Year Category at Landfall Pressure
    1 "Keys Labor Day" 1935 5 892 mb
    2 Camille 1969 5 900 mb
    3 Michael 2018 5 919 mb
    4 Katrina 2005 3 920 mb
    5 Andrew 1992 5 922 mb
    6 "Indianola" 1886 4 925 mb
    7 "FL Keys" 1919 4 927 mb
    8 "Okeechobee" 1928 4 929 mb
    9 "Great Miami" 1926 4 930 mb
    9 Donna 1960 4 930 mb

    * Hurricane Maria made landfall in Puerto Rico in 2017 as a category 4 with a pressure of 917 mb.

  • What were the strongest hurricanes on record to hit the U.S.?

    • Strongest U.S. Hurricanes at Landfall** (winds)
    Rank Hurricane Name Year Windspeed - mph / knots
    1 "Keys Labor Day" 1935 185 / 160
    2 Camille 1969 175 / 150
    3 Andrew 1992 165 / 145
    4 Michael 2018 160 / 140
    5 "Last Island" 1856 150 / 130
    5 "Indianola" 1886 150 / 130
    5 "FL Keys" 1919 150 / 130
    5 "Freeport" 1932 150 / 130
    5 Charley 2004 150 / 130
    10 "Great Miami" 1926 145 / 125
    10 "Okeechobee" 1928 145 / 125
    10 Donna 1960 145 / 125
    10 Carla 1961 145 / 125

    ** The San Felipe Segundo hurricane hit Puerto Rico with top sustained winds of 160 mph in 1928. It was the only category 5 on record to make landfall in Puerto Rico.

    * Hurricane Maria hit Puerto Rico with top sustained winds of 155 mph in 2017.

  • A sampling of the world's strongest tropical cyclones

    • World Tropical Cyclones
    Name Year Ocean Wind Pressure Comment
    Tip 1979 NW Pacific 190 mph 870 mb 160 mph 10 minute average / Lowest tropical cyclone pressure
    Patricia 2015 EPAC 215 mph 872 mb Most intense western hemisphere / strongest globally - 1 min avg.
    Zoe 2002 SW Pacific 180 mph 890 mb Record pressure for tropical cyclone southern hemisphere
    Haiyan 2013 NW Pacific 195 mph 895 mb 145 mph 10 minute average windspeed
    Allen 1980 Atlantic 190 mph 899 mb Strongest sustained winds for an Atlantic Hurricane
    Linda 1997 EPAC 185 mph 902 mb
    Ida 1958 NW Pacific 200 mph 877 mb Was the strongest tropical cyclone on record at time
    Wilma 2005 Atlantic 185 mph 882 mb Most intense Atlantic hurricane
    June 1975 NW Pacific 185 mph 875 mb First case of a triple eyewall
    Gafilo 2004 SW Indian 160 mph 895 mb


  • What was the strongest tropical cyclone on record in the world in terms of pressure?

    • The strongest tropical cyclone in the world was Typhoon Tip in 1979. It had a central pressure of 870 mb.

  • What were deadliest hurricanes on record to hit the U.S.?

    • The Deadliest U.S. Hurricanes (estimated)
    Rank Hurricane Name Year Category Deaths
    1 "Galveston" 1900 4 6000-12000
    2 "Okeechobee" 1928 4 2500
    3 Katrina 2005 3 1200
    4 "Cheniere Caminanda" 1893 4 1100-1400
    5 "Sea Islands" 1893 3 1000-2000
    6 GA/SC 1881 2 700
    7 Audrey 1957 4 416
    8 "Keys Labor Day" 1935 5 408
    9 "Last Island" 1856 4 400
    10 "Great Miami" 1926 4 372


  • What was the costliest hurricane on record to hit the U.S.?

    • Costliest U.S. Hurricanes* (not adjusted for inflation)
    Rank Hurricane Name Year Category Damage
    1 Harvey 2017 4 $125 billion
    1 Katrina 2005 3 $125 billion
    3 Sandy 2012 1 $65 billion
    4 Irma 2017 2 $50 billion
    5 Ike 2008 2 $30 billion
    6 Andrew 1992 5 $27 billion
    7 Michael 2018 5 $25 billion
    8 Ivan 2004 3 $20.5 billion
    9 Wilma 2005 3 $19 billion
    10 Rita 2005 3 $18.5 billion
    11 Charley 2004 4 $16 billion
    12 Irene 2011 1 $13.5 billion
    13 Matthew 2016 1 $10 billion


    * Hurricane Maria #3 hit Puerto Rico as a category 4 hurricane. $90 billion in damage.

  • What was the costliest hurricane on record to hit the U.S.?

    • Costliest U.S. Hurricanes** (adjusted for inflation)
    Rank Hurricane Name Year Category Damage
    1 Katrina 2005 3 $160 billion
    2 Harvey 2017 3 $125 billion
    3 Sandy 2012 1 $70.2 billion
    4 Irma 2017 2 $50 billion
    5 Andrew 1992 5 $47.79 billion
    6 Ike 2008 2 $34.8 billion
    7 Ivan 2004 3 $27.06 billion
    8 Michael 2018 5 $25 billion
    9 Wilma 2005 3 $24.32 billion
    10 Rita 2005 3 $23.68 billion
    101 Charley 2004 4 $21.12 billion
    12 Irene 2011 1 $14.985 billion
    13 Hugo 1989 4 $14.07 billion

    ** Hurricane Maria #3 hit Puerto Rico as a category 4 hurricane. $90 billion in damage.

  • What was the greatest number of hurricanes on record to hit the U.S.?


    • In 1916 and 1985 there were six U.S. landfalling hurricanes. In 1886 data suggests 7 U.S. landfalling hurricanes. Note that data from earlier years may not be totally reliable.

  • What was the fastest pressure drop for a hurricane?
    • The Fastest Pressure Drop in a Hurricane
    Hurricane Name Year 3 Hours 6 Hours 12 Hours 24 Hours
    Wilma 2005 44 mb 54 mb 87 mb 98 mb
    Gilbert 1988 47 mb 72 mb
    Felix 2007 50 mb 63 mb
    Allen 1980 48 mb 56 mb
    Beulah 1967 38 mb


  • What was the heaviest rainfall from a hurricane?

    • The heaviest rainfall from a hurricane was actually Tropical Cyclone Denise. 72 inches of rain fell in 24 hours in a place called Foc-Foc, La Reunion in 1966. The highest total was 239.5 inches in La Reunion from Cyclone Hyacinthe January 1980.

  • What was the highest measured wave from a tropical cyclone?


    • The highest measured wave was 112 feet high! It was measured by the USS Ramapo in the western Pacific February, 1933.

Back to the Tropicalweather.net Home Page. Data on hurricanes courtesy of the National Hurricane Center.