FACTOID # 30: If Alaska were its own country, it would be the 26th largest in total area, slightly larger than Iran.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
   
 
WHAT'S NEW
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Atlantic hurricane

Atlantic hurricane refers to a tropical cyclone that forms in the Atlantic Ocean north of the equator, usually in the Northern Hemisphere summer or autumn. Cyclone Catarina, a rare South Atlantic tropical cyclone viewed from the International Space Station on March 26, 2004. ... Insert non-formatted text here The Northern Hemisphere is the half of a planets surface (or celestial sphere) that is north of the equator (the word hemisphere literally means half ball). On the Earth, the Northern Hemisphere contains most of the land and population. ... For other senses of this word, see summer (disambiguation). ... Fall redirects here. ...


When applied to hurricanes, "Atlantic" generally refers to the entire "Atlantic basin," which includes the North Atlantic Ocean, Caribbean Sea and the Gulf of Mexico. Cyclone Catarina, a rare South Atlantic tropical cyclone viewed from the International Space Station on March 26, 2004. ... Map of Central America and the Caribbean The Caribbean Sea is a tropical body of water adjacent to the Atlantic Ocean and southeast of the Gulf of Mexico. ... Gulf of Mexico in 3D perspective. ...


Almost all Atlantic tropical storms and hurricanes form in the months of June through November. The Atlantic hurricane season officially runs from June 1 to November 30. The U.S. National Hurricane Center monitors the basin and issues reports, watches and warnings about tropical weather systems for the United States. Other countries around the basin track and issue warnings for tropical weather in their territories. Cyclone Catarina, a rare South Atlantic tropical cyclone viewed from the International Space Station on March 26, 2004. ... June 1 is the 152nd day of the year in the Gregorian calendar (153rd in leap years), with 213 days remaining. ... November 30 is the 334th day (335th on leap years) of the year in the Gregorian Calendar, with 31 days remaining, as the final day of November. ... The U.S. National Hurricane Center is the division of National Weather Services Tropical Prediction Center responsible for tracking and predicting the likely behavior of tropical depressions, tropical storms and hurricanes. ... The tropics are the geographic region of the Earth centered on the equator and limited in latitude by the two tropics: the Tropic of Cancer in the north and the Tropic of Capricorn in the southern hemisphere. ...


On average, 10.1 named storms -- disturbances that reach tropical storm intensity are named -- occur each season, with an average of 5.9 becoming hurricanes and 2.5 becoming major hurricanes (Category 3 or greater). The climatological peak of activity is around September 10 each season. The Saffir-Simpson Hurricane Scale is a scale classifying most Western Hemisphere tropical cyclones that exceed the levels of tropical depression and tropical storm and thereby become hurricanes. ... Climatology is the study of climate, and is a branch of the atmospheric sciences. ... September 10 is the 253rd day of the year (254th in leap years). ...

Contents


Steering factors

Tropical cyclones are steered by the surrounding flow throughout the depth of the troposphere (the atmosphere from the surface to about eight miles (12 km) high. Neil Frank, former director of the U.S. National Hurricane Center, used the analogy of a leaf carried along in a stream to describe the way atmospheric flow affects the path of a hurricane across the ocean. Specifically, air flow around high pressure systems and toward low pressure areas influence hurricane tracks. The Troposphere is the lowermost portion of Earths atmosphere. ... High pressure science and engineering is studying the effects of high pressure on materials and the design and construction of devices which can create high pressure. ... A low pressure area, or a low for short, is a region where the atmospheric pressure is lowest with relation to the surrounding area. ...


In the tropical latitudes, tropical storms and hurricanes generally move westward with a slight tend toward the north pole, under the influence of a high pressure axis, the subtropical ridge that extends east-west to the north of the tropics. South of the subtropical ridge, easterly winds (blowing from east to west) prevail. If the subtropical ridge is weakened by a trough in the jet stream or other conditions, however, a tropical cyclone may turn poleward and then recurve, or curve back toward the east. Poleward (north) of the subtropical ridge, westerly winds prevail and generally steer tropical cyclones that reach northern latitudes toward the east. The westerly winds (westerlies) also steer extratropical cyclones with their cold and warm fronts from west to east. The tropics are the geographic region of the Earth centered on the equator and limited in latitude by the two tropics: the Tropic of Cancer in the northern hemisphere and the Tropic of Capricorn in the southern hemisphere. ... Categories: Move to Wiktionary | Stub ... Jet streams are fast flowing, relatively narrow air currents found in the atmosphere at around 12 km above the surface of the Earth, just under the tropopause. ...

Modified after HRD FAQ E6, by Chris Landsea. This NOAA content is in the public domain.

Climatology

Probability of a tropical cyclone of tropical storm or hurricane strength at a specific date, expressed as systems per 100 years
Probability of a tropical cyclone of tropical storm or hurricane strength at a specific date, expressed as systems per 100 years
Tropical storms and hurricanes by month, for the period 1944-2005
(North Atlantic region)
Month Total Average
January–April 4 0.1
May 8 0.1
June 35 0.6
July 58 0.9
August 173 2.8
September 224 3.6
October 114 1.8
November 33 0.5
December 7 0.1
Source: NOAA + additions for 2001-05

Forecasting by climatology is very unreliable for use in any specific instances, but serves to characterize the general properties of an average season. Image File history File links Download high resolution version (831x546, 17 KB) Summary PNG version of [1] from [2], a prettified version of [3] from [4]. Not sure which years this graph is based on - neither page lists them. ... Image File history File links Download high resolution version (831x546, 17 KB) Summary PNG version of [1] from [2], a prettified version of [3] from [4]. Not sure which years this graph is based on - neither page lists them. ...


Most storms form in warm waters near the equator and the Intertropical convergence zone from tropical waves and other disturbances. Like all basins, few tropical systems form less than 10 degrees from the equator, as the Coriolis force is usually too weak to initiate sufficient rotation. Storms most often form in the warm waters of the Gulf of Mexico and the Caribbean Sea, and can form as far east as Cape Verde, producing strong and long-lasting Cape Verde-type hurricanes. Systems may also form, or retain or gain strength, over the Gulf Stream off the coast of the eastern United States. The equator is an imaginary circle drawn around a planet (or other astronomical object) at a distance halfway between the poles. ... The thunderstorms of the Intertropical Convergence Zone form a line across the eastern Pacific Ocean. ... It has been suggested that Easterly wave be merged into this article or section. ... In physics, the Coriolis effect is an inertial force first described by Gaspard-Gustave Coriolis, a French scientist, in 1835. ... Gulf of Mexico in 3D perspective. ... Map of Central America and the Caribbean The Caribbean Sea is a tropical body of water adjacent to the Atlantic Ocean and southeast of the Gulf of Mexico. ... Hurricane Ivan, a category 5 Cape Verde-type hurricane A Cape Verde-type hurricane is an Atlantic hurricane that develops near the Cape Verde islands, off the west coast of Africa. ... For the album by Ocean Colour Scene, see North Atlantic Drift (album) The Gulf Stream is orange and yellow in this representation of water temperatures of the Atlantic. ...


When a tropical system forms in a sufficiently southerly position, it initially travels west and slightly north while strengthening in warm water. After being approached by a trough moving west to east, most storms typically recurve to the northeast, following the trough. The turn happens at approximately the latitude of the Florida peninsula (25°N to 30°N). The storm weakens as it encounters cooler water or land, sometimes transitioning into an extratropical storm. A trough is an elongated region of relatively low atmospheric pressure, often associated with fronts. ... Official language(s) English Capital Tallahassee Largest city Jacksonville Area  - Total  - Width  - Length  - % water  - Latitude  - Longitude Ranked 22nd 170 451 km² 260 km 800 km 17. ... Extratropical is a term used in advisories and tropical summaries to indicate that a cyclone has lost its tropical characteristics. ...


Although most storms are found to the south and west, near the Gulf of Mexico and the Caribbean, occasionally storms will form further north and east from disturbances other than tropical waves.


There is a strong correlation between Atlantic hurricane activity and the presence of an El Niño or La Niña in the Pacific Ocean. El Niño events increase the wind shear over the Atlantic, producing a less-favorable environment for formation and decreasing tropical activity in the Atlantic basin. Conversely, La Niña causes an increase in activity due to a decrease in wind shear. [1] Chart of ocean surface temperature anomaly [°C] during the last strong El Niño in December 1997 El Niño and La Niña (also written in English as El Nino and La Nina) are major temperature fluctuations in surface waters of the tropical Eastern Pacific Ocean. ...


June

Typical locations and tracks of tropical systems in June. Blue is likely, green more likely, and orange most likely.
Typical locations and tracks of tropical systems in June. Blue is likely, green more likely, and orange most likely.

The beginning of the hurricane season is most closely related to the timing of increases in sea surface temperatures, convective instability, and other thermodynamical factors. [2] Although this month marks the beginning of the hurricane season, the month of June generally still sees little activity, with an average of about 3 tropical systems per 5 years. Image File history File links Typical_North_Atlantic_Tropical_Cyclone_Formation_in_June. ... Image File history File links Typical_North_Atlantic_Tropical_Cyclone_Formation_in_June. ...


Any tropical systems usually form in the Gulf of Mexico or off the east coast of the United States. Gulf of Mexico in 3D perspective. ...

July

Typical locations and tracks in July.
Typical locations and tracks in July.

July still has relatively little activity, with about one tropical cyclone a year. Climatologically speaking, half of seasons have their first tropical storm by July 11 with a second by August 8, using data from 1944 to 1996. Image File history File links Typical_North_Atlantic_Tropical_Cyclone_Formation_in_July. ... Image File history File links Typical_North_Atlantic_Tropical_Cyclone_Formation_in_July. ... July 11 is the 192nd day (193rd in leap years) of the year in the Gregorian Calendar, with 173 days remaining. ... August 8 is the 220th day of the year in the Gregorian Calendar (221st in leap years), with 145 days remaining. ...


Formation usually occurs in the eastern Caribbean Sea around the Lesser Antilles, in the north and east parts of the Gulf of Mexico, in the northern Bahamas, and off the coast of The Carolinas and Virginia. Storms travel west through the Caribbean and then either move more northerly and curving near the eastern coast of the U.S. or southerly and entering the Gulf of Mexico. Map of Central America and the Caribbean The Caribbean Sea is a tropical body of water adjacent to the Atlantic Ocean and southeast of the Gulf of Mexico. ... The Lesser Antilles are part of the Antilles, which together with the Bahamas form the West Indies. ... The Carolinas is a collective term used in the United States to refer to the states of North and South Carolina together. ... Official language(s) English Capital Richmond Largest city Virginia Beach Area  - Total  - Width  - Length  - % water  - Latitude  - Longitude Ranked 35th 110,862 km² 320 km 690 km 7. ...

August

Typical locations and tracks in August.
Typical locations and tracks in August.

Activity increases significantly in August, with an average of about 2.8 storms per year. About half of seasons have four named systems and one hurricane total by August 30. The average season also sees one major hurricane by September 4. Image File history File links Typical_North_Atlantic_Tropical_Cyclone_Formation_in_August. ... Image File history File links Typical_North_Atlantic_Tropical_Cyclone_Formation_in_August. ... August 30 is the 242nd day of the year in the Gregorian Calendar (243rd in leap years), with 123 days remaining. ... September 4 is the 247th day of the year (248th in leap years). ...

September

Typical locations and tracks in September.
Typical locations and tracks in September.

The peak of the hurricane season in September corresponds to a time with low wind shear and high sea surface temperatures. [citation needed] The month of September sees an average of 3.6 storms a year. By September 24, the average season sees 7 named systems, of which 4 are hurricanes. In addition, two major hurricanes would be seen by September 28. Image File history File links Typical_North_Atlantic_Tropical_Cyclone_Formation_in_September. ... Image File history File links Typical_North_Atlantic_Tropical_Cyclone_Formation_in_September. ... Wind shear jake rinow is the god of technologyis a difference in wind speed or direction between two points in the atmosphere. ... Visualisation of the SST of the ocean just before Hurricane Bob (August 14, 1991) Sea surface temperature (SST) is the water temperature at 1 meter below the sea surface. ... September 24 is the 267th day of the year (268th in leap years). ... September 28 is the 271st day of the year in the Gregorian calendar (272nd in leap years). ...

October

Typical locations and tracks in October.
Typical locations and tracks in October.

The favorable conditions found during September begin to decay in October. The main reason for the decrease in activity is increasing wind shear, although sea surface temperatures are also usually cooler than in September. [2] Activity falls off markedly, with 1.8 cyclones developing in an average season. By October 21, the average season is expected to have 9 named storms with 5 hurricanes. A third major hurricane would be expected sometime between September 28 and the end of the year for half of all seasons. Image File history File links Typical_North_Atlantic_Tropical_Cyclone_Formation_in_October. ... Image File history File links Typical_North_Atlantic_Tropical_Cyclone_Formation_in_October. ... October 21 is the 294th day of the year (295th in leap years) in the Gregorian Calendar, with 71 days remaining. ... September 28 is the 271st day of the year in the Gregorian calendar (272nd in leap years). ...


Although tropical activity is lower than in September, another small peak in activity occurs around October 20. [citation needed] October 20 is the 293rd day of the year (294th in leap years) in the Gregorian Calendar, with 72 days remaining. ...

November

Typical locations and tracks in November.
Typical locations and tracks in November.

Wind shear from westerlies increases substantially through November, generally preventing cyclone formation. [2] On average, one storm forms during November every other year. Image File history File links Typical_North_Atlantic_Tropical_Cyclone_Formation_in_November. ... Image File history File links Typical_North_Atlantic_Tropical_Cyclone_Formation_in_November. ... The westerlies are the prevailing winds in the middle latitudes between 30 and 60 degrees latitude, blowing from the high pressure area in the horse latitudes towards the poles. ...

December to May

Few tropical cyclones can be found in the time between seasons. In the 61 seasons between 1944 and 2005, only 8 tropical cyclones have formed in May, 7 in December, and 4 total for all four months between January and April. High wind shear and low sea surface temperatures generally preclude formation. Though a tropical cyclone has been observed in the Atlantic basin in every month in the year, no tropical cyclone has initially formed in January. However, a subtropical cyclone formed in January in the 1978 season, and both Hurricane Alice and Tropical Storm Zeta formed in December and lasted into January. (For additional information, see Off-season storms.) A subtropical cyclone is a weather system that has some characteristics of a tropical cyclone and some characteristics of an extratropical cyclone. ... The 1978 Atlantic hurricane season was an ongoing event in the annual cycle of tropical cyclone formation. ... Hurricane Alice was the only hurricane in the history of the Atlantic basin known to span two calendar years, and one of only two named tropical cyclones (along with Tropical Storm Zeta of 2005) to do so. ... Tropical Storm Zeta was the late-developing twenty-seventh named storm of the 2005 Atlantic hurricane season. ... This is a list of notable Atlantic hurricanes, subdivided by reason for notability. ...


Extremes

This is a list of notable Atlantic hurricanes, subdivided by reason for notability. ... The 2005 Atlantic hurricane season officially began on June 1, 2005, and lasted until November 30, 2005. ... The 1950 Atlantic hurricane season was an on going event in the annual cycle of tropical cyclone formation. ... The 1983 Atlantic hurricane season was an ongoing event in the annual cycle of tropical cyclone formation. ... Hurricane Wilma, the most intense hurricane ever recorded in the Atlantic basin, devastated parts of the Yucatán Peninsula and southern Florida during October in the 2005 Atlantic hurricane season. ... The 2005 Atlantic hurricane season officially began on June 1, 2005, and lasted until November 30, 2005. ... A millibar (mbar, also mb) is 1/1000th of a bar, a unit for measurement of pressure. ... Hurricane San Ciriaco was an Atlantic tropical cyclone which crossed Puerto Rico over the two day period August 8 to August 9, 1899, causing many deaths from the flooding. ... The New England Hurricane of 1938 (or Great New England Hurricane or Long Island Express) was the first major hurricane to strike New England since 1869. ... Miles per hour is a unit of speed, expressing the number of international miles covered per hour. ... B C D E F G H I 10 J K L M N O Categories: | | | | | ... First storm formed: August 1, 2004 Last storm dissipated: December 2, 2004 Strongest storm: Ivan - 910 mbar (26. ... The Labor Day Hurricane was a very compact, intense hurricane that caused catastrophic destruction in the Florida Keys on September 2, 1935. ... The Great Hurricane of 1780 is considered the deadliest Atlantic tropical cyclone of all time. ... Hurricane Katrina was the costliest and one of the deadliest hurricanes in American history. ... The 2005 Atlantic hurricane season officially began on June 1, 2005, and lasted until November 30, 2005. ... This article is about general United States currency. ...

See also

   
Tropical cyclones Portal

Image File history File links Download high resolution version (1000x662, 320 KB) http://eol. ... Cyclone Catarina, a rare South Atlantic tropical cyclone viewed from the International Space Station on March 26, 2004. ... This is a list of notable Atlantic hurricanes, subdivided by reason for notability. ... ... A South Atlantic tropical cyclone is an unusual weather event which occurs in the southern Atlantic Ocean, south of the equator. ...

References

  1. http://www.aoml.noaa.gov/hrd/Landsea/elnino/
  2. a b c http://hurricane.atmos.colostate.edu/forecasts/2005/nov2005/ Dr. William Gray's 2005 season summary

External links


  Results from FactBites:
 
NCDC: Climate of 2005: Atlantic Hurricane Season Summary (5570 words)
Strengthening to reach hurricane intensity on the 29th as it moved northward, Beta then turned to the west and west-southwest and became a category 3 storm on the 30th, the 7th major hurricane of the season.
Hurricane Katrina was one of the strongest storms to impact the coast of the United States during the last 100 years.
Hurricane Irene was a long-lived storm originating from a tropical wave moving off the coast of Africa.
NCDC: Climate of 2004: Atlantic Hurricane Season Summary (3864 words)
Of additional interest was the development, in March, of a hurricane in the South Atlantic, the only documented hurricane in that basin to impact land, and the first hurricane in the South Atlantic to be recorded in the satellite era.
Hurricane Frances was at category four strength (140 mph, 122 kts) as it moved towards the southeastern Bahamas, passing over the Turks and Caicos Islands on September 1st.
Hurricane strength was briefly reached on October 1st for Lisa, though the storm began to weaken the next day in the far North Atlantic becoming extratropical about 475 miles north-northwest of the Azores.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m