The eye is a region of mostly calm weather found at the center of strong tropical cyclones. The weather is a set of all the phenomena occurring in a given Atmosphere at a given Time. A tropical cyclone is a storm system characterized by a low pressure center and numerous Thunderstorms that produce strong winds and Flooding The eye of a storm is a roughly circular area and typically 30–65 km (20–40 miles) in diameter. A storm is any disturbed state of an astronomical body's atmosphere, especially affecting its surface and strongly implying Severe weather. The kilometre ( American spelling: kilometer) symbol km is a unit of Length in the Metric system, equal to one thousand A mile is a unit of Length, usually used to measure Distance, in a number of different systems including Imperial units United States Geometry, a diameter of a Circle is any straight Line segment that passes through the center of the circle and whose Endpoints are on the It is surrounded by the eyewall, a ring of towering thunderstorms where the most severe weather of a cyclone occurs. The cyclone's lowest barometric pressure occurs in the eye, and can be as much as 15% lower than the atmospheric pressure outside the storm. ^[1]

In strong tropical cyclones, the eye is characterized by light winds and clear skies, surrounded on all sides by a towering, symmetric eyewall. Wind is the flow of Air or other Gases that compose an Atmosphere (including but not limited to the Earth's) In weaker tropical cyclones, the eye is less well-defined, and can be covered by the central dense overcast, which is an area of high, thick clouds which show up brightly on satellite imagery. A cloud is a visible mass of droplets or frozen crystals floating in the atmosphere above the surface of the Earth or another Planetary body Satellite imagery consists of photographs of Earth or other planets made by means of Artificial satellites. Weaker or disorganized storms may also feature an eyewall which does not completely encircle the eye, or have an eye which features heavy rain. Rain is Liquid precipitation. On Earth it is the condensation of atmospheric Water vapor into drops heavy enough to fall often making it to In all storms, however, the eye is the location of the storm's minimum barometric pressure: the area where the atmospheric pressure at sea level is the lowest. ^[1][2]

Tropical cyclones
Formation and naming
Development - Structure Naming - Seasonal lists - Full list
Effects
Effects Watches and warnings Storm surge - Notable storms Retired names (Atlantic - Eastern Pacific - Western Pacific)
Climatology and tracking
Basins - RSMCs - TCWCs - Scales Observation - Forecasting Rainfall forecasting Rainfall climatology
Part of the Nature series: Weather

Structure

A cross section diagram of a mature tropical cyclone, with arrows indicating air flow in and around the eye

A typical tropical cyclone will have an eye approximately 30–65 km (20–40 mi) across, usually situated at the geometric center of the storm. A tropical cyclone is a storm system characterized by a low pressure center and numerous Thunderstorms that produce strong winds and Flooding Tropical cyclogenesis is the technical term describing the development and strengthening of a Tropical cyclone in the Atmosphere. Presently most Tropical cyclones are given a name using one of several Lists of tropical cyclone names. Due to their long-term persistence and the need for a unique identifier in issuing forecasts and warnings Tropical cyclones and Subtropical cyclones are given names according This is a list of named tropical cyclones, giving all official names for Tropical cyclones. The effects of tropical cyclones are the impacts that Tropical cyclones have on the areas they move through Warnings and watches are two levels of alert issued by national Weather forecasting bodies to coastal areas threatened by the imminent approach of a Tropical cyclone Storm surge or tidal surge is an offshore rise of water associated with a low pressure weather system typically a Tropical cyclone. This is a list of notable Tropical cyclones, subdivided by basin and reason for notability Tropical cyclone names may be retired (removed from the name list in several Tropical cyclone basins around the world by the World Meteorological Organization This is a list of retired Atlantic hurricane names. Hurricane names are retired by the World Meteorological Organization (WMO in a meeting in March April or May Wikipedia_talkFeatured_lists#Proposed_change_to_all_featured_lists for an explanation of this and other inclusion tags below -->This is a list of all Pacific This is a list of all Pacific typhoons that have had their names retired by the Japan Meteorological Agency. Northwestern Pacific Ocean See also Pacific typhoon The Northwest Pacific Ocean is the most active basin on the planet A Regional Specialized Meteorological Centre (also Regional Specialized Meteorological Center and Regional Specialised Meteorological Centre) is responsible for the A Tropical Cyclone Warning Centre is one of six regional warning centers that are part of the World Meteorological Organization Tropical cyclone programme and act Tropical cyclones are ranked according to their maximum winds using several scales Tropical cyclone observation has been carried out over the past couple of centuries in various ways Tropical cyclone forecasting is the science and art of forecasting where a Tropical cyclone 's center and its effects are expected to be at some point in the future Tropical cyclone rainfall forecasting involves using scientific models and other tools to predict the precipitation expected in Tropical cyclones such as hurricanes and typhoons A tropical cyclone rainfall climatology is developed to determine rainfall characteristics of past tropical cyclones Nature, in the broadest sense is equivalent to the natural world, physical universe, material world or material universe. The weather is a set of all the phenomena occurring in a given Atmosphere at a given Time. In Geometry, a cross section is the intersection of a body in 2-dimensional space with a line or of a body in 3-dimensional space with a plane etc The eye may be clear or have spotty low clouds (a clear eye), it may be filled with low- and mid-level clouds (a filled eye), or it may be obscured by the central dense overcast. A cloud is a visible mass of droplets or frozen crystals floating in the atmosphere above the surface of the Earth or another Planetary body There is, however, very little wind and rain, especially near the center. This is in stark contrast to conditions in the eyewall, which contains the storm's strongest winds. ^[3] Due to the mechanics of a tropical cyclone, the eye and the air directly above it are warmer than their surroundings. A tropical cyclone is a storm system characterized by a low pressure center and numerous Thunderstorms that produce strong winds and Flooding ^[4]

While normally quite symmetric, eyes can be oblong and irregular, especially in weakening storms. A large ragged eye is a non-circular eye which appears fragmented, and is an indicator of a weak or weakening tropical cyclone. An open eye is an eye which can be circular, but the eyewall does not completely encircle the eye, also indicating a weakening, moisture-deprived cyclone. Both of these observations are used to estimate the intensity of tropical cyclones via Dvorak analysis. ^[5] Eyewalls are typically circular; however, distinctly polygonal shapes ranging from triangles to hexagons occasionally occur. Regular hexagon The internal Angles of a regular hexagon (one where all sides and all angles are equal are all 120 ° and the hexagon has 720 degrees ^[6]

While typical mature storms have eyes that are a few dozen miles across, rapidly intensifying storms can develop an extremely small, clear, and circular eye, sometimes referred to as a pinhole eye. Rapid deepening, also know as rapid intensification, is a meteorological condition that occurs when the minimum sea-level Atmospheric pressure of a Storms with pinhole eyes are prone to large fluctuations in intensity, and provide difficulties and frustrations for forecasters. ^[7]

Hurricane Nate, as seen in this picture on September 6, 2005, presents a cloud-filled eye. Hurricane Nate was a Hurricane over the Atlantic during September in the 2005 Atlantic hurricane season. Events 3114 BC - According to the Proleptic Julian calendar the current era in the Maya Long Count Calendar started Year 2005 ( MMV) was a Common year starting on Saturday (link displays full calendar of the Gregorian calendar.

Small eyes—those less than 10 nmi (19 km, 12 mi) across—often trigger eyewall replacement cycles, where a new eyewall begins to form outside the original eyewall. A nautical mile or sea mile is a unit of Length. It corresponds approximately to one minute of Latitude along any meridian. A mile is a unit of Length, usually used to measure Distance, in a number of different systems including Imperial units United States This can take place anywhere from ten to a few hundred miles (fifteen to hundreds of kilometers) outside the inner eye. The storm develops two concentric eyewalls, or an "eye within an eye". In most cases, the outer eyewall begins to contract soon after its formation, which chokes off the inner eye and leaves a much larger but more stable eye. While the replacement cycle tends to weaken storms as it occurs, the new eyewall can contract fairly quickly after the old eyewall dissipates, allowing the storm to re-strengthen. This may trigger another cycle of eyewall replacement. ^[8]

Eyes can range in size from 320 km (200 miles) (Typhoon Carmen) to a mere 3 km (2 mi) (Hurricane Wilma) across. The 1960 Pacific typhoon season had no official bounds it ran year-round in 1960 but most tropical cyclones tend to form in the northwestern Pacific Ocean between June Hurricane Wilma was the most intense hurricane ever recorded in the Atlantic basin. ^[9] While it is uncommon for storms with large eyes to become very intense, it does occur, especially in annular hurricanes. An annular hurricane is a Tropical cyclone in the Atlantic or Eastern Pacific Oceans that features a large symmetric eye surrounded by a Hurricane Isabel was the eleventh most powerful Atlantic hurricane in recorded history, and sustained a large, 65–80 km (40–50 mi)-wide eye for a period of several days. Hurricane Isabel was the costliest and deadliest hurricane in the 2003 Atlantic hurricane season. ^[10]

Formation and detection

See also: Tropical cyclogenesis

Tropical cyclones form when the energy released by the condensation of moisture in rising air causes a positive feedback loop over warm ocean waters. Tropical cyclogenesis is the technical term describing the development and strengthening of a Tropical cyclone in the Atmosphere. Positive feedback, sometimes referred to as "cumulative causation" is a Feedback loop system in which the system responds to perturbation in the same direction

Typically, eyes are easy to spot using weather radar. A weather radar is a type of Radar used to locate precipitation, calculate its motion estimate its type ( Rain This radar image of Hurricane Andrew clearly shows the eye over southern Florida. Hurricane Andrew is the second most powerful and the last of three Category 5 hurricanes that made U Florida ( is a state located in the southeastern region of the United States, bordering Alabama to the northwest and Georgia to the

Tropical cyclones typically form from large, disorganized areas of disturbed weather in tropical regions. The Tropics are centered on the Equator and limited in Latitude by the Tropic of Cancer in the northern hemisphere at approximately 23°26' (23 As more thunderstorms form and gather, the storm develops rainbands which start rotating around a common center. A tropical cyclone is a storm system characterized by a low pressure center and numerous Thunderstorms that produce strong winds and Flooding As the storm gains strength, a ring of stronger convection forms at a certain distance from the rotational center of the developing storm. Convection in the most general terms refers to the movement of molecules within Fluids (i Since stronger thunderstorms and heavier rain mark areas of stronger updrafts, the barometric pressure at the surface begins to drop, and air begins to build up in the upper levels of the cyclone. An updraft or downdraft ( air pocket) is the vertical movement of Air as a Weather related phenomenon ^[11] This results in the formation of an upper level anticyclone, or an area of high atmospheric pressure above the central dense overcast. In Meteorology, an anticyclone (that is opposite to a Cyclone) is a Weather phenomenon in which there is a descending movement of the air and Consequentially, most of this built up air flows outward anticyclonically above the tropical cyclone. Outside the forming eye, the anticyclone at the upper levels of the atmosphere enhances the flow towards the center of the cyclone, pushing air towards the eyewall and causing a positive feedback loop. Positive feedback, sometimes referred to as "cumulative causation" is a Feedback loop system in which the system responds to perturbation in the same direction ^[11]

However, a small portion of the built-up air, instead of flowing outward, flows inward towards the center of the storm. This causes air pressure to build even further, to the point where the weight of the air counteracts the strength of the updrafts in the center of the storm. Air begins to descend in the center of the storm, creating a mostly rain-free area; a newly-formed eye. ^[11]

There are many aspects of this process which remain a mystery. Scientists do not know why a ring of convection forms around the center of circulation instead of on top of it, or why the upper-level anticyclone only ejects a portion of the excess air above the storm. Hundreds of theories exist as to the exact process by which the eye forms: all that is known for sure is that the eye is necessary for tropical cyclones to achieve high wind speeds. ^[11]

The formation of an eye is almost always an indicator of increasing tropical cyclone organisation and strength. Because of this, forecasters watch developing storms closely for signs of eye formation.

For storms with a clear eye, detection of the eye is as simple as looking at pictures from a weather satellite. A weather satellite is a type of Satellite that is primarily used to monitor the Weather and Climate of the Earth. However, for storms with a filled eye, or an eye completely covered by the central dense overcast, other detection methods must be used. Observations from ships and Hurricane Hunters can pinpoint an eye visually, by looking for a drop in wind speed or lack of rainfall in the storm's center. Hurricane Hunters are aircraft that fly into Tropical cyclones in the North Atlantic Ocean and Northeastern Pacific Ocean for the specific purpose of In the United States, South Korea, and a few other countries, a network of NEXRAD Doppler weather radar stations can detect eyes near the coast. The United States of America —commonly referred to as the South Korea, officially the Republic of Korea and often referred to as Korea ( Korean: 대한민국 tɛː NEXRAD or Nexrad ( Nex t-Generation Rad ar is a network of 158 high-resolution Doppler Weather radars operated by the National Weather A weather radar is a type of Radar used to locate precipitation, calculate its motion estimate its type ( Rain Weather satellites also carry equipment for measuring atmospheric water vapor and cloud temperatures, which can be used to spot a forming eye. General properties of water vapor Evaporation/sublimation Whenever a water molecule leaves a surface it is said to have evaporated In addition, scientists have recently discovered that the amount of ozone in the eye is much higher than the amount in the eyewall, due to air sinking from the ozone-rich stratosphere. OZONE is an object oriented Operating system written in the C programming language. Instruments sensitive to ozone perform measurements, which are used to observe rising and sinking columns of air, and provide indication of the formation of an eye, even before satellite imagery can determine its formation. Satellite imagery consists of photographs of Earth or other planets made by means of Artificial satellites. ^[12]

Associated phenomena

Eyewall replacement cycles

A satellite photo of Typhoon Amber of the 1997 Pacific typhoon season, exhibiting an outer and inner eyewall while undergoing an eyewall replacement cycle. The 1997 Pacific typhoon season has no official bounds it ran year-round in 1997 but most Tropical cyclones tend to form in the northwestern Pacific Ocean between

Eyewall replacement cycles, also called concentric eyewall cycles, naturally occur in intense tropical cyclones, generally with winds greater than 185 km/h (115 mph), or major hurricanes (Category 3 or above). A tropical cyclone is a storm system characterized by a low pressure center and numerous Thunderstorms that produce strong winds and Flooding The Saffir-Simpson Hurricane Scale is a classification used for most Western Hemisphere Tropical cyclones that exceed the intensities of Tropical depressions When tropical cyclones reach this threshold of intensity, and the eyewall contracts or is already sufficiently small (see above), some of the outer rainbands may strengthen and organize into a ring of thunderstorms—an outer eyewall—that slowly moves inward and robs the inner eyewall of its needed moisture and angular momentum. In Physics, the angular momentum of a particle about an origin is a vector quantity equal to the mass of the particle multiplied by the Cross product of the position Since the strongest winds are located in a cyclone's eyewall, the tropical cyclone usually weakens during this phase, as the inner wall is "choked" by the outer wall. Eventually the outer eyewall replaces the inner one completely, and the storm can re-intensify.

The discovery of this process was partially responsible for the end of the U. S. government's hurricane modification experiment Project Stormfury. Project Stormfury was an attempt to weaken Tropical cyclones by flying aircraft into them and seeding with Silver iodide. This project set out to seed clouds outside the eyewall, causing a new eyewall to form and weakening the storm. Cloud seeding, a form of weather modification, is the attempt to change the amount or type of precipitation that falls from Clouds by dispersing substances When it was discovered that this was a natural process due to hurricane dynamics, the project was quickly abandoned. ^[8]

Almost every intense hurricane undergoes at least one of these cycles during its existence. Hurricane Allen in 1980 went through repeated eyewall replacement cycles, fluctuating between Category 5 and Category 3 status on the Saffir-Simpson Scale several times. Hurricane Allen was the strongest Hurricane of the 1980 Atlantic hurricane season. The Saffir-Simpson Hurricane Scale is a classification used for most Western Hemisphere Tropical cyclones that exceed the intensities of Tropical depressions Hurricane Juliette was a rare documented case of triple eyewalls. Hurricane Juliette was a long lasting Category 4 Hurricane in the 2001 Pacific hurricane season. ^[13]

Moats

A moat in a tropical cyclone is a clear ring outside the eyewall, or between concentric eyewalls, characterized by slowly sinking air, little or no precipitation, and strain-dominated flow. ^[14] The moat between eyewalls is just one example of a rapid filamentation zone, or an area in the storm where the rotational speed of the air changes greatly in proportion to the distance from the storm's center. Such strain-dominated regions can potentially be found near any vortex of sufficient strength, but are most pronounced in strong tropical cyclones. V erification of the O rigins of R otation in T ornadoes Ex periment or VORTEX, is a field project that seeks to understand how a

Eyewall mesovortices

Eyewall mesovortices are small scale rotational features found in the eyewalls of intense tropical cyclones. They are similar, in principle, to small "suction vortices" often observed in multiple-vortex tornadoes. A multiple vortex tornado is a Tornado that contains several vortices rotating around inside of and as part of the main Vortex. In these vortices, wind speed can be up to 10% higher than in the rest of the eyewall. Eyewall mesovortices are most common during periods of intensification in tropical cyclones.

Eyewall mesovortices often exhibit unusual behavior in tropical cyclones. They usually rotate around the low pressure center, but sometimes they remain stationary. Eyewall mesovortices have even been documented to cross the eye of a storm. These phenomena have been documented observationally,^[15] experimentally,^[16] and theoretically. ^[17]

Eyewall mesovortices are a significant factor in the formation of tornadoes after tropical cyclone landfall. A tornado is a violent rotating column of air which is in contact with both the surface of the earth and a Cumulonimbus cloud or in rare cases the base of a Cumulus Mesovortices can spawn rotation in individual thunderstorms (a mesocyclone), which leads to tornadic activity. A mesocyclone is a Vortex of air approximately 2 to 10 km in diameter (the Mesoscale of meteorology within a convective Storm At landfall, friction is generated between the circulation of the tropical cyclone and land. This can allow the mesovortices to descend to the surface, causing large outbreaks of tornadoes.

Stadium effect

A picture of Hurricane Wilma's eye taken at 08:22 CDT (13:22 UTC) October 19, 2005, by the crew aboard the International Space Station. Hurricane Wilma was the most intense hurricane ever recorded in the Atlantic basin. The Central Time Zone observes Standard time by subtracting six hours from UTC during standard time ( UTC−6) and five hours during Daylight saving Events 202 BCE - The Battle of Zama results in the defeat of Carthage and Hannibal. Year 2005 ( MMV) was a Common year starting on Saturday (link displays full calendar of the Gregorian calendar. At the time, Wilma was the strongest Atlantic hurricane in history, with a minimum central pressure of only 882 mbar (26. The bar (symbol bar) decibar (symbol dbar) and the millibar (symbol mbar, also mb are units of Pressure. 06 inHg). Inches of mercury, inHg or "Hg is a measuring unit for Pressure. ^[18] Not only is this a classic example of a pinhole eye, but also of the stadium effect, where the eyewall slopes out and up.

The stadium effect is a phenomenon observed in strong tropical cyclones. It is a fairly common event, where the clouds of the eyewall curve outward from the surface with height. This gives the eye an appearance resembling an open dome from the air, akin to a sports stadium. A modern stadium (plural stadiums or stadia in English is a place or venue for (mostly outdoor Sports Concerts or other events consisting An eye is always larger at the top of the storm, and smallest at the bottom of the storm because the rising air in the eyewall follows isolines of equal angular momentum, which also slope outward with height. A contour line (also Level set, isopleth, isoline, isogram or isarithm) of a function of two In Physics, the angular momentum of a particle about an origin is a vector quantity equal to the mass of the particle multiplied by the Cross product of the position ^[19][20][21] This phenomenon refers to the characteristics of tropical cyclones with very small eyes, where the sloping phenomenon is much more pronounced.

Eye-like features

An eye-like structure is often found in intensifying tropical cyclones. Similar to the eye seen in hurricanes or typhoons, it is a circular area at the circulation center of the storm in which convection is absent. A storm is any disturbed state of an astronomical body's atmosphere, especially affecting its surface and strongly implying Severe weather. Convection in the most general terms refers to the movement of molecules within Fluids (i These eye-like features are most normally found in intensifying tropical storms and hurricanes of category 1 strength on the Saffir-Simpson Scale. The Saffir-Simpson Hurricane Scale is a classification used for most Western Hemisphere Tropical cyclones that exceed the intensities of Tropical depressions For example, an eye-like feature was found in Hurricane Beta when the storm had maximum wind speeds of 50 mph. Hurricane Beta was the twenty-third named storm fourteenth hurricane, and seventh major hurricane of the record-breaking 2005 Atlantic hurricane season. Wind speed is the Speed of Wind, the movement of air or other gases in an atmosphere ^[22] These eye-like features are typically not visible on visible wavelengths or infrared wavelengths from space, however, they are easily seen on microwave satellite imagery. Infrared ( IR) radiation is Electromagnetic radiation whose Wavelength is longer than that of Visible light, but shorter than that of Microwaves are electromagnetic waves with Wavelengths ranging from 1 mm to 1 m or frequencies between 0 ^[23] The development of this feature at mid level is similar to the formation of the complete eye but its position might be different due to the vertical wind shear^[24][25]

Hazards

Though the eye is by far the calmest part of the storm, with no wind at the center and typically clear skies, over the ocean it is possibly the most hazardous area. In the eyewall, wind-driven waves are all traveling in the same direction. In the center of the eye, however, waves from all directions converge, creating erratic crests which can build on each other, creating rogue waves. Rogue waves, also known as freak waves, monster waves or extreme waves, are relatively large and spontaneous Ocean surface waves that are a threat The maximum height of hurricane waves is unknown, but measurements of Hurricane Ivan, when it was a category four hurricane, estimated that waves near the eyewall were in excess of 40 meters (130 ft) from peak to trough. Hurricane Ivan was the strongest hurricane of the 2004 Atlantic hurricane season. The metre or meter is a unit of Length. It is the basic unit of Length in the Metric system and in the International A foot (plural feet or foot; symbol or abbreviation ft or sometimes &prime – the prime symbol) is a non-SI unit ^[26] This is in addition to any storm surge which may occur, as storm surges often extend into the eye. Storm surge or tidal surge is an offshore rise of water associated with a low pressure weather system typically a Tropical cyclone.

A common mistake, especially in areas where hurricanes are uncommon, is for residents to wander outside to inspect the damage while the eye passes over, thinking the storm is over. They are then caught completely by surprise by the violent winds in the opposite eyewall. The National Weather Service strongly discourages leaving shelter while the eye passes over. The National Weather Service ( NWS) once known as the Weather Bureau is one of the six scientific agencies that make up the National Oceanic and Atmospheric Administration ^[27]

Other storms

Main article: Cyclone

Though only tropical cyclones have structures which are officially called "eyes", there are other storms which can exhibit eye-like structures:

Polar lows

Polar lows are mesoscale weather systems (typically smaller than 1,000 km or 600 miles across) found near the poles. In Meteorology, a cyclone refers to an area of closed circular fluid motion rotating in the same direction as the Earth. A polar low is a small-scale short-lived atmospheric low pressure system (depression that is found over the ocean areas poleward of the main Polar front in Mesoscale Meteorology is the study of Weather systems smaller than Synoptic scale systems but larger than microscale and Storm-scale cumulus A geographical pole, or geographic pole, is either of two fixed points on the surface of a spinning body or Planet, at 90 degrees from the Equator, based Like tropical cyclones, they form over relatively warm water, can feature deep convection (thunderstorms), and feature winds of gale force (51 km/h, 32 mph) or greater. The Beaufort scale (ˈboʊfət is an Empirical measure for describing Wind speed based mainly on observed sea conditions Unlike storms of tropical nature, however, they thrive in much colder temperatures and at much higher latitudes. Latitude, usually denoted symbolically by the Greek letter phi ( Φ) gives the location of a place on Earth (or other planetary body north or south of the They are also smaller and last for shorter durations (few last longer than a day or so). Despite these differences, they can be very similar in structure to tropical cyclones, featuring a clear eye surrounded by an eyewall and rain/snow bands. ^[28]

Extratropical storms

The North American blizzard of 2006, an extratropical storm, showed an eye-like structure at its peak intensity (here seen just to the east of the Delmarva Peninsula). The Blizzard of 2006 was a Nor'easter that began on the evening of February 11, 2006. The Delmarva Peninsula is a large Peninsula on the East Coast of the United States, occupied by portions of three U

Extratropical storms are areas of low pressure which exist at the boundary of different air masses. Extratropical cyclones, sometimes called mid-latitude cyclones or wave cyclones, are a group of Cyclones defined as synoptic scale low For airmass in Astronomy, see Airmass. In Meteorology, an air mass is a large volume of Air that Almost all storms found at mid-latitudes are extratropical in nature, including classic North American nor'easters and European windstorms. A nor'easter (also northeaster; see below is a macro-scale Storm along the East Coast of the United States and Atlantic Canada. A European windstorm is a severe cyclonic storm that tracks across the North Atlantic towards northwestern Europe in the winter months The most severe of these can have a clear "eye" at the site of lowest barometric pressure, though it is usually surrounded by lower, non-convective clouds and is found near the back end of the storm. ^[29]

Subtropical storms

Subtropical storms are cyclones which have some extratropical characteristics and some tropical characteristics. A subtropical cyclone is a Weather system that has some characteristics of a Tropical cyclone and some characteristics of an Extratropical cyclone. As such, they may have an eye, but are not true tropical storms. Subtropical storms can be very hazardous, with high winds and seas, and often evolve into true tropical storms. As such, the National Hurricane Center began including subtropical storms in their naming scheme in 2002. The US National Hurricane Center, located at Florida International University in Miami Florida, is the division of National Weather Service See also 2002 (disambiguation Year 2002 ( MMII) was a Common year starting on Tuesday of the Gregorian calendar. ^[30]

Tornadoes

Tornadoes are destructive, small-scale storms, which produce the fastest winds on earth. A tornado is a violent rotating column of air which is in contact with both the surface of the earth and a Cumulonimbus cloud or in rare cases the base of a Cumulus There are two main types—single-vortex tornadoes, which consist of a single spinning column of air, and multiple-vortex tornadoes, which consist of small suction vortices, resembling mini-tornadoes themselves, all rotating around a common center. Both of these types of tornadoes are theorized to have calm centers, referred to by some meteorologists as "eyes". These theories are supported by doppler velocity observations by weather radar^[31] and eyewitness accounts. ^[32]

Extraterrestrial storms

A hurricane-like storm on the south pole of Saturn displaying an eyewall tens of kilometers high

NASA reported in November 2006 that the Cassini spacecraft observed a 'hurricane-like' storm locked to the south pole of Saturn that had a clearly defined eyewall. The National Aeronautics and Space Administration ( NASA, ˈnæsə is an agency of the United States government, responsible for the nation's public space program A tropical cyclone is a storm system characterized by a low pressure center and numerous Thunderstorms that produce strong winds and Flooding This observation is particularly notable because eyewall clouds have not been seen on any planet other than Earth (including a failure to observe an eyewall in the Great Red Spot of Jupiter by the Galileo spacecraft). Galileo was an Unmanned spacecraft sent by NASA to study the Planet Jupiter and its moons Named after the Astronomer ^[33] In 2007, very large vortices[1] on both poles of Venus are observed by the Venus Express mission of the European Space Agency to have a dipole eye structure. The VENUS ( V ictoria E xperimental N etwork U nder the S ea project is a cabled sea floor observatory operated by the University Venus Express is the first Venus exploration mission of the European Space Agency. The European Space Agency ( ESA) established in 1975 is an intergovernmental organisation dedicated to the exploration of space, currently with 17 member ^[34]

See also

• List of tropical cyclones
• Radius of maximum wind
• Storm surge
• Tropical cyclone

References

External links

• Atlantic Oceanographic and Meteorological Laboratory
• Canadian Hurricane Centre: Glossary of Hurricane Terms