Hurricanes
Fortunately, as a general rule, we are given sufficient warning to prepare for a hurricane. This preparation period should consist of immediate plans to ready yourself, your family and your home for an emergency. Depending on many factors the warning could be issued days in advance or as little as a few hours.
Watch vs. Warning - Know The Difference
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A HURRICANE WATCH issued for your part of the coast indicates the possibility that you could experience hurricane conditions within 36 hours. This watch should trigger your family's disaster plan, and protective measures should be initiated, etc.
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A HURRICANE WARNING issued for your part of the coast indicates that sustained winds of at least 74 mph are expected within 24 hours or less. Once this warning has been issued, your family should be in the process of completing protective actions and deciding on the safest location to be during the storm.
Hurricane BasicsThe ingredients for a hurricane include a pre-existing weather disturbance, warm tropical oceans, moisture, and relatively light winds aloft. If the right conditions persist long enough, they can continue to produce the violent winds, incredible waves, torrential rains, and floods we associate with this phenomenon.
Each year, an average of ten tropical storms develop over the Atlantic Ocean, Caribbean Sea, and Gulf of Mexico. Many of these remain over the ocean and never impact the U.S. coastline. Six of these storms become hurricanes each year. In an average 3-year period, roughly five hurricanes strike the US coastline, killing approximately 50 to 100 people anywhere from Texas to Maine. Of these, two are typically "major" or "intense" hurricanes (a category 3 or higher storm on the Saffir-Simpson Hurricane Scale.
What Is A Hurricane?
A hurricane is a type of tropical cyclone, which is a generic term for a low pressure system that generally forms in the tropics. The cyclone is accompanied by thunderstorms and, in the Northern Hemisphere, a counterclockwise circulation of winds near the earths surface. Tropical cyclones are classified as follows:
Tropical Depression An organized system of clouds and thunderstorms with a defined surface circulation and maximum sustained winds* of 38 mph (33 kt**) or less. |
* Sustained Winds A 1-minute average wind measured at about 33 ft (10 meters) above the surface. ** 1 Knot = 1 nautical mile per hour or 1.15 statute miles per hour. Abbreviated as "kt" |
Tropical Storm An organized system of strong thunderstorms with a defined surface circulation and maximum sustained winds of 39 - 73 mph (34-63 kt) |
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Hurricane An intense tropical weather system of strong thunderstorms with a well-defined surface circulation and maximum sustained winds of 74 mph (64 kt) or higher. |
Hurricanes are categorized according to the strength of their wins using the Saffir-Simpson Hurricane Scale A Category 1 storm has the lowest wind speeds, while a category 5 hurricane has the strongest. These are relative terms, because lower category storms can sometimes inflict greater damage than higher category storms, depending on where they strike and the particular hazards they bring. In fact, tropical storms can also produce significant damage and loss of life, mainly due to flooding.
Hurricane Category Information
Tropical Storm
Winds 39 - 73 mph
Category One Hurricane:
Winds 74-95 mph (64-82 kt or 119-153 km/hr). Storm surge generally 4-5 ft above normal. No real damage to building structures. Damage primarily to unanchored mobile homes, shrubbery, and trees. Some damage to poorly constructed signs. Also, some coastal road flooding and minor pier damage.
Category Two Hurricane:
Winds 96-110 mph (83-95 kt or 154-177 km/hr). Storm surge generally 6-8 feet above normal. Some roofing material, door, and window damage of buildings. Considerable damage to shrubbery and trees with some trees blown down. Considerable damage to mobile homes, poorly constructed signs, and piers. Coastal and low-lying escape routes flood 2-4 hours before arrival of the hurricane center. Small craft in unprotected anchorages break moorings.
Category Three Hurricane:
Winds 111-130 mph (96-113 kt or 178-209 km/hr). Storm surge generally 9-12 ft above normal. Some structural damage to small residences and utility buildings with a minor amount of curtainwall failures. Damage to shrubbery and trees with foliage blown off trees and large trees blown down. Mobile homes and poorly constructed signs are destroyed. Low-lying escape routes are cut by rising water 3-5 hours before arrival of the center of the hurricane. Flooding near the coast destroys smaller structures with larger structures damaged by battering from floating debris. Terrain continuously lower than 5 ft above mean sea level may be flooded inland 8 miles (13 km) or more. Evacuation of low-lying residences with several blocks of the shoreline may be required.
Category Four Hurricane:
Winds 131-155 mph (114-135 kt or 210-249 km/hr). Storm surge generally 13-18 ft above normal. More extensive curtainwall failures with some complete roof structure failures on small residences. Shrubs, trees, and all signs are blown down. Complete destruction of mobile homes. Extensive damage to doors and windows. Low-lying escape routes may be cut by rising water 3-5 hours before arrival of the center of the hurricane. Major damage to lower floors of structures near the shore. Terrain lower than 10 ft above sea level may be flooded requiring massive evacuation of residential areas as far inland as 6 miles (10 km).
Category Five Hurricane:
Winds greater than 155 mph (135 kt or 249 km/hr). Storm surge generally greater than 18 ft above normal. Complete roof failure on many residences and industrial buildings. Some complete building failures with small utility buildings blown over or away. All shrubs, trees, and signs blown down. Complete destruction of mobile homes. Severe and extensive window and door damage. Low-lying escape routes are cut by rising water 3-5 hours before arrival of the center of the hurricane. Major damage to lower floors of all structures located less than 15 ft above sea level and within 500 yards of the shoreline. Massive evacuation of residential areas on low ground within 5-10 miles (8-16 km) of the shoreline may be required.
Hurricane season officially begins June 1 and runs through November 30 each year.
Hurricane Names:
When the winds from these storms reach 39 mph (34 kts), the cyclones are given names. Years ago, an international committee developed names for Atlantic cyclones (The History of Naming Hurricanes). In 1979 a six year rotating list of Atlantic storm names was adopted — alternating between male and female hurricane names. Storm names are used to facilitate geographic referencing, for warning services, for legal issues, and to reduce confusion when two or more tropical cyclones occur at the same time. Through a vote of the World Meteorological Organization Region IV Subcommittee, Atlantic cyclone names are retired usually when hurricanes result in substantial damage or death or for other special circumstances. The names assigned for the period between 2017 and 2022 are shown below.
Names For Atlantic Basin Tropical Cyclones | |||||
2017 | 2018 | 2019 | 2020 | 2021 | 2022 |
Arlene | Alberto | Andrea | Arthur | Ana | Alex |
Bret | Beryl | Barry | Bertha | Bill | Bonnie |
Cindy | Chris | Chantal | Cristobal | Claudette | Colin |
Don | Debby | Dorian | Dolly | Danny | Danielle |
Emily | Ernesto | Erin | Edouard | Elsa | Earl |
Franklin | Florence | Fernand | Fay | Fred | Fiona |
Gert | Gordon | Gabrielle | Gonzalo | Grace | Gaston |
Harvey | Helene | Humberto | Hanna | Henri | Hermine |
Irma | Isaac | Imelda | Isaias | Ida | Ian |
Jose | Joyce | Jerry | Josephine | Julian | Julia |
Katia | Kirk | Karen | Kyle | Kate | Karl |
Lee | Leslie | Lorenzo | Laura | Larry | Lisa |
Maria | Michael | Melissa | Marco | Mindy | Martin |
Nate | Nadine | Nestor | Nana | Nicholas | Nicole |
Ophelia | Oscar | Olga | Omar | Odette | Owen |
Philippe | Patty | Pablo | Paulette | Peter | Paula |
Rina | Rafael | Rebekah | Rene | Rose | Richard |
Sean | Sara | Sebastien | Sally | Sam | Shary |
Tammy | Tony | Tanya | Teddy | Teresa | Tobias |
Vince | Valerie | Van | Vicky | Victor | Virginie |
Whitney | William | Wendy | Wilfred | Wanda | Walter |