A low-pressure area, depression or cyclone is a region on the topographic map where the atmospheric pressure is lower than that of surrounding locations. Low-pressure systems form under areas of wind divergence that occur in the upper levels of the troposphere; the formation process of a low-pressure area is known as cyclogenesis. Within the field of meteorology, atmospheric divergence aloft occurs in two areas; the first area is on the east side of upper troughs, which form half of a Rossby wave within the Westerlies. A second area of wind divergence aloft occurs ahead of embedded shortwave troughs, which are of smaller wavelength. Diverging winds aloft ahead of these troughs cause atmospheric lift within the troposphere below, which lowers surface pressures as upward motion counteracts the force of gravity. Thermal lows form due to localized heating caused by greater sunshine over deserts and other land masses. Since localized areas of warm air are less dense than their surroundings, this warmer air rises, which lowers atmospheric pressure near that portion of the Earth's surface.
Large-scale thermal lows over continents help drive monsoon circulations. Low-pressure areas can form due to organized thunderstorm activity over warm water; when this occurs over the tropics in concert with the Intertropical Convergence Zone, it is known as a monsoon trough. Monsoon troughs reach their southerly extent in February; when a convective low acquires a well-hot circulation in the tropics it is termed a tropical cyclone. Tropical cyclones can form during any month of the year globally, but can occur in either the northern or southern hemisphere during December. Atmospheric lift will generally produce cloud cover through adiabatic cooling once the air becomes saturated as it rises, although the low-pressure area brings cloudy skies, which act to minimize diurnal temperature extremes. Since clouds reflect sunlight, incoming shortwave solar radiation decreases, which causes lower temperatures during the day. At night the absorptive effect of clouds on outgoing longwave radiation, such as heat energy from the surface, allows for warmer diurnal low temperatures in all seasons.
The stronger the area of low pressure, the stronger the winds experienced in its vicinity. Globally, low-pressure systems are most located over the Tibetan Plateau and in the lee of the Rocky mountains. In Europe, recurring low-pressure weather systems are known as "depressions". Cyclogenesis is the development and strengthening of cyclonic circulations, or low-pressure areas, within the atmosphere. Cyclogenesis is the opposite of cyclolysis, has an anticyclonic equivalent which deals with the formation of high-pressure areas—anticyclogenesis. Cyclogenesis is an umbrella term for several different processes, all of which result in the development of some sort of cyclone. Meteorologists use the term "cyclone" where circular pressure systems flow in the direction of the Earth's rotation, which coincides with areas of low pressure; the largest low-pressure systems are cold-core polar cyclones and extratropical cyclones which lie on the synoptic scale. Warm-core cyclones such as tropical cyclones and polar lows lie within the smaller mesoscale.
Subtropical cyclones are of intermediate size. Cyclogenesis can occur from the microscale to the synoptic scale. Larger-scale troughs called Rossby waves, are synoptic in scale. Shortwave troughs embedded within the flow around larger scale troughs are smaller in scale, or mesoscale in nature. Both Rossby waves and shortwaves embedded within the flow around Rossby waves migrate equatorward of the polar cyclones located in both the Northern and Southern hemispheres. All share one important aspect, that of upward vertical motion within the troposphere; such upward motions decrease the mass of local atmospheric columns of air, which lowers surface pressure. Extratropical cyclones form as waves along weather fronts due to a passing by shortwave aloft or upper level jet streak before occluding in their life cycle as cold-core cyclones. Polar lows are small-scale, short-lived atmospheric low-pressure systems that occur over the ocean areas poleward of the main polar front in both the Northern and Southern Hemispheres.
They are part of the larger class of mesoscale weather-systems. Polar lows can be difficult to detect using conventional weather reports and are a hazard to high-latitude operations, such as shipping and gas- and oil-platforms, they are vigorous systems. Tropical cyclones form due to latent heat driven by significant thunderstorm activity, are warm-core with well-defined circulations. Certain criteria need to be met for their formation. In most situations, water temperatures of at least 26.5 °C are needed down to a depth of at least 50 m. Another factor is rapid cooling with height, which allows the release of the heat of condensation that powers a tropical cyclone. High humidity is needed in the lower-to-mid troposphere. Low amounts of wind shear are needed. Lastly, a formative tropical cyclone needs a pre-existing system of disturbed weather, although without a circulation no cyclonic development will take place. Mesocyclones form as warm core cyclones over land, c
Manzanillo is a city, seat of Manzanillo Municipality, in the Mexican state of Colima. The city, located on the Pacific Ocean, contains Mexico's busiest port, responsible for handling Pacific cargo for the Mexico City area, it is the largest producing municipality for the business tourism in the state of Colima. The city is known as the "sailfish capital of the world". Since 1957, it has hosted important national and international fishing competitions, such as the Dorsey Tournament, making it a attractive fishing destination. Manzanillo has become one of the country's most important tourist resorts, its excellent hotels and restaurants continue to meet the demands of both national and international tourism. 16th centuryIn 1522, Gonzalo de Sandoval, under orders from conquistador Hernan Cortes, dropped anchor in the Bay of Salagua, looking for safe harbors and good shipbuilding sites. In the year before he left, Sandoval granted an audience to local Indian chieftains in a small cove, which today carries the name Playa de La Audiencia.
A great part of his fleet, which left to conquer the Philippines, was constructed in Salagua. Manzanillo Bay was discovered in 1527 by navigator Alvaro de Saavedra, naming it Santiago de la Buena Esperanza, or Santiago's Bay of Good Hope. Manzanillo was the third port created by the Spanish in the Viceroyalty of New Spain, it became a departure point for important expeditions. Cortes visited the bay twice to protect his galleons from Portuguese pirates. Over the next 300 years, the Pacific Coast’s history is filled with accounts of pirates from Portugal, England and Spain assaulting and burning ships for their rich cargos. 19th centuryIn 1825 the Port of Manzanillo opened, in independent Mexico, so named because of the abundant groves of native Manzanilla trees that were used extensively in the early days of shipbuilding. Manzanillo was raised to the status of a city on 15 June 1873; the railroad to Colima was completed in 1889. 20th centuryIn 1908, President Porfirio Diaz designated Manzanillo as an official port of entry to Mexico.
It was the state capital of Colima from 20 February to 1 March 1915, while Pancho Villa’s troops were threatening to capture the city of Colima. In the 2005 census, the city of Manzanillo had a population of 110,728 and in 2010 its municipality had 161,420, it is the second-largest community in the state, after the capital. The municipality covers an area of 1,578.4 km2, includes such outlying communities as El Colomo, in addition to many smaller communities. Manzanillo is a beach resort, is one of many locations to promote themselves as the "sailfish capital" of the world.. One way they promote; the Revillagigedo Islands, off the west coast of Mexico in the Pacific Ocean, are part of the municipality, but they are directly administered by the federal government. Manzanillo is a sister city of the U. S. cities of Flagstaff, Arizona. The city is well known internationally for deep-sea fishing and the green flash phenomenon during sunsets, as well as the warm waters of the ocean; the city is a destination resort and has many hotels and self-contained resorts built on the De Santiago peninsula which juts out into the Pacific north of the city centre.
At the north end of Manzanillo bay is the resort Las Hadas, the most famous of the city's resorts, having been featured in the movie 10 starring Bo Derek and Dudley Moore. Beach scenes were filmed on La Audencia Bay, just over the hill from Las Hadas. Manzanillo is a popular cruise ship port of call. Many tourists go from their cruise ships on city tours. Excellent swimming and scuba diving is found in Santiago Bay, a few miles north of the city where a cargo ship sank in a hurricane in 1959. Other wrecks and reefs plentiful with fish are scattered throughout the bay. Manzanillo is known as the Sailfish Capital of the World. Since 1957, it has hosted important national and international fishing competitions, such as the Dorsey Tournament, making it a attractive fishing destination. Manzanillo consists of two bays with crescent-shaped beaches, each about 4 miles in length. Bahía de Manzanillo is the older tourist section. Bahía de Santiago, to the west, is the more upscale area; the two are separated by the Santiago Peninsula.
Ship channels are located at the southeast end of Bahía de Manzanillo where large cruise ships enter the port area. Manzanillo was once the scene of adventure. By 2011, its peaceful bays and sophisticated tourist and port infrastructure had made it one of the main tourist resorts and trading centers in the west of Mexico. On 6 July 2010, the Secretariat of Communications and Transportation opened a specialized dock for cruise ships at the port, which involved an investment of $100 million pesos in the first stage. A second phase foresees the construction of a shopping centre. Manzanillo has a tropical savanna climate; the dry season, from November to May, has low amounts of precipitation, temperatures tend to be cooler than in the wet season. The average temperature in March, the coolest month, is 24 °C; the wet season, which runs from June to October, has warmer temperatures, averaging 28.3 °C in July, humidity during this time is higher. In 2012, the port of Manzanillo initiated an ecological project consisting of dredged canals and creating islands in the Lagoon of the Valle de las Garzas, a protected wildlife area.
With this work, the port pla
2010 Pacific hurricane season
The 2010 Pacific hurricane season is the least active Pacific hurricane season, alongside 1977, since reliable records began in 1971. It started on May 15, 2010 for the eastern Pacific, June 1 for the central Pacific, ended on November 30. Unlike the previous season, the first storm of the season, formed during the month of May. Agatha developed on May 29 near the coast of Guatemala. In the second week of June, a sudden spree of tropical cyclones developed, between June 16 and 22, four cyclones formed, including the two major hurricanes of the season and Darby, the first of which reached Category 5 intensity. However, following the record active June, July saw zero named storms. In August and September only 2 tropical storms and one hurricane formed. Tropical Depression Eleven-E caused a great deal of flooding in southern Mexico, causing millions of dollars in damage, as well as causing over 50 deaths and $500 million in damage in areas of Oaxaca and Guatemala. Tropical Storm Omeka was a rare off-season storm.
On May 19, 2010, the National Oceanic and Atmospheric Administration released their forecast for the 2010 Central Pacific hurricane season, which would start on June 1. They expected two or three cyclones to form in or enter the region throughout the season, below the average of four or five storms; the below-average activity forecast was based on two factors: the first was the continuance of a period of decreased activity in the central Pacific. However, in light of the near-miss of Hurricane Felicia the previous year, forecasters at the Central Pacific Hurricane Center gave the public a basic message for the 2010 season, "Prepare! Watch! Act!". On May 27, 12 days after the official start of the 2010 eastern Pacific hurricane season, NOAA released their forecast for the basin. Similar to the forecast for the central Pacific, below-average activity was expected, with nine to fifteen named storms forming, four to eight of which would become hurricanes and a further one to three would become major hurricanes.
This lessened activity was based on the same two factors as the central Pacific, decreased activity since 1995 and the ENSO event. Overall, NOAA stated there was a 75% chance of below-average activity, 20% of near-normal and only a 5% chance of above-average. Continuing a trend of below-average activity that began in 1995, the 2010 season was quiet as expected; the Eastern Pacific proper saw record-low numbers of named storms and hurricanes, with only seven and three forming. Inclusive of the Central Pacific, the basin tied its record low activity of eight named storms set in 1977; the lack of storms was reflected by an Accumulated Cyclone Energy value of 50 units 46 percent of the long-term median. This ranked 2010 as the third-quietest since 1966, just above 1977 and 2007; the vast majority of the ACE stemmed from Hurricanes Celia and Darby, which collectively accounted for 70 percent of the seasonal total. Inactivity was attributed to a moderately strong La Niña event which resulted in below-average sea surface temperatures across the basin.
Another major factor limiting storm formation was the eastward displacement of 200 mb divergence. The displacement of this feature brought conditions that favor tropical development closer to the rugged terrain of Mexico and Central America, a factor known to disrupt low-level circulations. Accordingly, six of the seven named storms in the Eastern Pacific proper formed east of 106°W, four of which originated over the Gulf of Tehuantepec where the greatest depth of warm waters were restricted to. A final limiting factor was above-average wind shear across much of the basin east of 130°W and north of 10°N; the season began with record-high activity. ACE values exceeded 300 percent of the long-term mean, though most was due to Category 5 Hurricane Celia. Hurricane Celia was the second-earliest forming storm of that intensity during the course of a season, surpassed only by Hurricane Ava in 1973; the month featured an ACE value of 37.22, eclipsing the previous record set in 1984. Furthermore, Darby was the earliest second major hurricane of a season, eclipsing 1978's Hurricane Daniel.
This activity abruptly languished throughout the month of July. No named storms developed during the month, marking the first such occurrence since 1966. However, due to the activity in June, ACE value for the season by the start of August remained above normal 107 percent the yearly mean. Through the remainder of the season, the basin observed record low activity with only three additional named storms developing; the record inactivity experienced in the Northeastern Pacific took place in the Northwestern Pacific. Since reliable records began in the 1970s, there has been no precedent for both basins experiencing exceptionally low tropical cyclone formation. Moreover, this general lack of storm formation was reflected in all cyclone basins except the Atlantic. On average, the Northeastern Pacific accounts for 16 percent of the world's storms. Early May 29, the season's first tropical depression consolidated near the Gulf of Tehuantepec. Large-scale southwesterly flow prompted the system to move northeast.
Scatterometer data indicated the depression soon strengthened into a tropical storm, at which time it was assigned the name Agatha. Attaining peak winds of 45 mph, Agatha soon made landfall late on May 29 near Champerico, just south of the border with Mex
Tropical Storm Aletta (1982)
Tropical Storm Aletta was a weak but destructive tropical storm that killed 308 people while meandering off the coast of Central America in May 1982. An area of disturbed weather developed into a tropical depression on May 20, into a tropical storm around noon on May 21; the cyclone turned northeast, reaching its peak as a strong tropical storm on May 23. Aletta meandered and weakened, dissipating a few hundred miles southwest of Acapulco on May 29. Moisture from the tropical system spread over Nicaragua, causing flooding. Throughout the two countries, 308 people were killed and total damage was at $466 million. In the aftermath of the storm, many programs provided relief to the victims of Aletta; the origins of Aletta are from a tropical disturbance, first noted on May 18 about 500 mi south-southwest of Acapulco. On May 20, satellite imagery showed evidence of a weak atmospheric circulation. Based on this, the disturbance was upgraded into a tropical depression. Moving northwest, the depression became Tropical Storm Aletta 36 hours over 86 °F sea surface temperatures.
The system re-curved towards the northeast due to strong upper-level westerlies, reaching its peak intensity of 65 mph on May 23. Shortly after its peak, Tropical Storm Aletta began to weaken. However, the tropical cyclone managed to maintain winds of 50 mph for 30 hours before resuming a weakening trend. While the steering currents weakened on May 25, Aletta slowed and moved in a large clockwise loop until May 28. Shortly thereafter, Tropical Storm Aletta was downgraded into a depression. Tropical Depression Aletta dissipated on May 29 180 mi southwest of Acapulco; the outer rainbands of Tropical Storm Aletta produced torrential rains and high winds over Central America for several days, precipitation totals were as high as 23.3 in in some areas with a peak of 57.32 in in Chinandega. A red cross official stated that "Entire families were swept away by and we know nothing about them"; because all sewers in Nicaragua were damaged, the water was contaminated. Ninety percent of the banana crop and 60 percent of the corn crop was destroyed.
Throughout the country, 108 people were killed. 20,000 people were homeless and total damage was estimated at $365 million. In the northern portion of the country, a mudslide buried three small mountain villages, leaving 270 missing and only 29 survivors. About 15,000 sought to two emergency shelters. Many bridges were damaged. Since the capital city of Leon was hardest hit, a disaster area was declared for the nearby area. Aletta was considered the worst disaster in the country in three years. Across Honduras, 200 people were killed and 5,000 people were without food or water in just 13 communities. A total of 80,000 people were homeless which were housed in schools and health victims. Total damage was placed at $101 million. On May 27, the governments of both Honduras and Nicaragua appealed for international aid. Soldiers sent food and medical to at least 50 communities in both countries. A second appeal was made shortly afterwards, which proposed for $5.1 million in medicine and other supplies.
The red cross and United Nations appealed for $3 million in international relief. The UN granted Nicaragua a month's worth of food supply, but officials feared that this would not be enough; the government of Cuba announced that they would send 12,000 construction workers as well as 2,000 teachers and officials to Nicaragua. Canada donated $220,000 via the League of Red Cross Societies. To prevent an epidemic of diseases such as typhoid fever, the Health Ministry started a program to give out vaccines which costs $5.1 million. The U. S. Embassy in Managua provided $25,000 in donations; the U. S. Embassy in Honduras attempted to outline a fact-fining mission to assess the damage and provide relief. 1982 Pacific hurricane season List of wettest tropical cyclones Other tropical cyclones named Aletta
The pascal is the SI derived unit of pressure used to quantify internal pressure, Young's modulus and ultimate tensile strength. It is defined as one newton per square metre, it is named after the French polymath Blaise Pascal. Common multiple units of the pascal are the hectopascal, equal to one millibar, the kilopascal, equal to one centibar; the unit of measurement called. Meteorological reports in the United States state atmospheric pressure in millibars. In Canada these reports are given in kilopascals; the unit is named after Blaise Pascal, noted for his contributions to hydrodynamics and hydrostatics, experiments with a barometer. The name pascal was adopted for the SI unit newton per square metre by the 14th General Conference on Weights and Measures in 1971; the pascal can be expressed using SI derived units, or alternatively SI base units, as: 1 P a = 1 N m 2 = 1 k g m ⋅ s 2 = 1 J m 3 where N is the newton, m is the metre, kg is the kilogram, s is the second, J is the joule. One pascal is the pressure exerted by a force of magnitude one newton perpendicularly upon an area of one square metre.
The unit of measurement called a standard atmosphere is 101325 Pa.. This value is used as a reference pressure and specified as such in some national and international standards, such as the International Organization for Standardization's ISO 2787, ISO 2533 and ISO 5024. In contrast, International Union of Pure and Applied Chemistry recommends the use of 100 kPa as a standard pressure when reporting the properties of substances. Unicode has dedicated code-points U+33A9 ㎩ SQUARE PA and U+33AA ㎪ SQUARE KPA in the CJK Compatibility block, but these exist only for backward-compatibility with some older ideographic character-sets and are therefore deprecated; the pascal or kilopascal as a unit of pressure measurement is used throughout the world and has replaced the pounds per square inch unit, except in some countries that still use the imperial measurement system or the US customary system, including the United States. Geophysicists use the gigapascal in measuring or calculating tectonic stresses and pressures within the Earth.
Medical elastography measures tissue stiffness non-invasively with ultrasound or magnetic resonance imaging, displays the Young's modulus or shear modulus of tissue in kilopascals. In materials science and engineering, the pascal measures the stiffness, tensile strength and compressive strength of materials. In engineering use, because the pascal represents a small quantity, the megapascal is the preferred unit for these uses; the pascal is equivalent to the SI unit of energy density, J/m3. This applies not only to the thermodynamics of pressurised gases, but to the energy density of electric and gravitational fields. In measurements of sound pressure or loudness of sound, one pascal is equal to 94 decibels SPL; the quietest sound a human can hear, known as the threshold of hearing, is 20 µPa. The airtightness of buildings is measured at 50 Pa; the units of atmospheric pressure used in meteorology were the bar, close to the average air pressure on Earth, the millibar. Since the introduction of SI units, meteorologists measure pressures in hectopascals unit, equal to 100 pascals or 1 millibar.
Exceptions include Canada. In many other fields of science, the SI is preferred. Many countries use the millibars. In all other fields, the kilopascal is used instead. Atmospheric pressure which gives the usage of the hbar end the mbar Centimetre of water Meteorology Metric prefix Orders of magnitude Pascal's law Pressure measurement
Hurricane Manuel was the most destructive eastern Pacific tropical cyclone on record. Manuel brought widespread flooding across much of Mexico in September 2013, along with Hurricane Ingrid, which hit the opposite side of the nation the same day as Manuel, the first such occurrence since 1958; the fifteenth named storm and seventh hurricane of the annual hurricane season, Manuel originated from a strong area of low pressure south of Acapulco on September 13. Within favorable conditions aloft, the storm intensified into a tropical storm as it tracked northward; the following day, Manuel curved westward and strengthened to a point just shy of hurricane intensity before making its first landfall at that intensity on September 15. Due to interaction with land, the tropical storm weakened, its center dissipated over western Mexico on September 16. However, the storm's remnants continued to track northwestward into the Gulf of California, where they reorganized into a tropical cyclone the next day.
Manuel regained tropical storm status on September 18. Shortly thereafter, Manuel attained hurricane intensity, before making its final landfall just west of Culiacán at peak intensity. Over land, Manuel weakened due to interaction with Mexico's high terrain, the storm dissipated early on September 20. Due to the impending threat of Manuel, several Mexican municipalities were put under disaster alerts. Upon making its first landfall, Manuel caused extreme flooding in southern Mexico. Property and agricultural damage as a result of the system was widespread, one million people were estimated to have been directly affected. In Guerrero, 97 people perished, including 18 in Acapulco. Seventy-one others died due to a mudslide in La Pintada. In Guerrero alone, around 30,000 homes were damaged and 46 rivers overflowed their banks. There, 20,000 persons were evacuated to shelters. Statewide, repairs to damage from the storm totaled MXN$3 billion. Other impacts from Manuel spread as far east as the Isthmus of Tehuantepec, where 300 families were displaced.
In the region, at least 11,591 homes were destroyed by the floods. Meanwhile, the nation sustained additional impacts from Atlantic Hurricane Ingrid. After its second landfall, additional floods occurred in several towns, in Sinaloa over 100,000 people were rendered homeless and four people died; as a result of Manuel's impacts, 107 municipalities were declared disaster regions. Damage in Sinaloa totaled MXN$500 million; the Mexican Army was dispatched in several locations to aid in post-tropical cyclone relief operations. Following the storm, looting in impacted areas became commonplace, as such government forces were dispatched to prevent further looting. Overall, 169 people lost their lives in Mexico; the origins of Manuel can be traced back to a tropical wave that left the African continent in late August. The wave entered the Caribbean Sea on September 5, although the northern portion of the wave axis developed into Hurricane Ingrid. On September 10, the National Hurricane Center remarked the potential for a low-pressure area to develop off the southwest coast of Mexico during the subsequent few days, provided the system remained offshore.
The next day, a low formed while it was nearly stationary, accompanied by scattered convection. Strong wind shear and proximity to land were expected to limit development, although conditions became more favorable on September 12. On that day, the convection became better organized. At 1200 UTC on September 13, the NHC initiated advisories on Tropical Depression Thirteen-E, noting that the system had enough of a well-defined circulation and convection. By that time, wind shear had diminished and warm waters were expected to allow intensification, the main inhibiting factors for development were proximity to Mexico and association with the intertropical convergence zone. Within a few hours of developing, the depression intensified into Tropical Storm Manuel. By early on September 14, an eye feature developed. However, Manuel was embedded within a broad weather system that extended from the eastern Pacific across Mexico, which included Hurricane Ingrid in the Bay of Campeche on the Gulf of Mexico coast.
The broad system, including Manuel, moved northward. By early on September 15, Manuel had developed a central dense overcast, with a 17 mi wide eye in the center. Based on the structure and satellite-intensity estimates, the NHC estimated Manuel attained secondary peak winds of 70 mph, just shy of hurricane status; the agency noted the potential for further strengthening into a hurricane, citing the warm waters, moist environment, low shear. A break in the subtropical ridge to the north allowed the storm to continue to the north-northeast, but after attaining its secondary peak, Manuel turned back to the northwest while accelerating. On September 15, Manuel made landfall near Aquila in Michoacán as a high-end tropical storm, though operationally, it was believed to have moved ashore near Manzanillo in Colima. Early on September 16, the storm weakened into a tropical depression after the circulation became disrupted, although it continued dropping heavy rainfall; that day, the surface center dissipated over western Mexico.
The remnants of Manuel tracked northwest around a ridge situated over the southeastern United States, late on September 16, emerged over open waters. Despite only marginally favorable conditions, convection soon increased over the center. At 1800 UTC on September 17 Manuel regenerated into a tropical depression after redeveloping a well-defined circulation. Furthermore, conditions favored additional strengtheni
1982 Pacific hurricane season
The 1982 Pacific hurricane season, with 23 named storms, ranks as the fourth-most active Pacific hurricane season on record, tied with 2018. It was at that time the most active season in the basin until it was surpassed by the 1992 season, it started June 1, 1982, in the eastern Pacific, June 1, 1982, in the central Pacific, lasted until October 31, 1982, in the central Pacific and until November 15, 1982, in the Eastern Pacific. These dates conventionally delimit the period of each year when most tropical cyclones form in the northeastern Pacific Ocean. At that time, the season was considered as the most active season within the basin; the 1982 season was an eventful one. Hurricane Paul killed over 1,000 people. Hurricanes Daniel and Gilma both threatened Hawaii, while Hurricane Iwa caused heavy damage to Kauai and Niihau; the remnants of Hurricane Olivia brought heavy rain to a wide swath of the western United States. This season had twenty-three tropical storms, twelve hurricanes, five major hurricanes.
Three tropical storms and one hurricane— a record number of named storms— formed in the central Pacific. This was due to the strong 1982–83 El Niño event, present during the season. However, this was surpassed in the 2015 Pacific hurricane season with eight storms; this is the first year that named storms forming between the dateline and 140°W were given names from the Hawaiian language. Previous to this year and numbers from the western Pacific's typhoon list were used. After this year, it was decided that the six-year lists would be used, instead of the four-year ones; that is. The origins of Aletta are from a tropical disturbance, first noted on May 18 about 500 mi south-southwest of Acapulco. On May 20, the disturbance was upgraded into a tropical depression. Moving northwest, the depression became Tropical Storm Aletta 36 hours later; the system re-curved towards the northeast due to strong upper-level westerlies, reaching its peak intensity of 65 mph on May 23. Shortly after its peak, Tropical Storm Aletta began to weaken.
However, the system leveled off in intensity for 30 hours before resuming a weakening trend. On May 25, Aletta slowed and moved in a large clockwise loop until May 28. Shortly thereafter, Tropical Storm Aletta was downgraded into a depression. Tropical Depression Aletta dissipated on May 29 180 mi southwest of Acapulco; the outer rainbands of Tropical Storm Aletta produced torrential rains and high winds over Central America for several days, with a peak of 57.32 in in Chinandega. Ninety percent of the banana crop and 60 percent of the corn crop was destroyed. Throughout the country, 108 people were killed, Roughly 20,000 people were homeless and total damage was estimated at $365 million. In one village, the storm left only 29 survivors; the capital city of Leon was hardest hit by Aletta, considered the worst disaster in the country in three years. Across Honduras, 200 people were killed and 5,000 people were without food or water 13 communities. A total of 80,000 people were homeless. Total damage was placed at $101 million.
Following the storm, soldiers sent food and medical to at least 50 communities in both countries. To prevent an epidemic of diseases such as typhoid fever, the Health Ministry started a program to give out vaccines. In addition, the U. S. Embassy in Honduras attempted to outline a fact-fining mission to assess the damage and provide relief; this system originated as a low in the western Caribbean Sea on the morning of May 27. The next day it moved southwest into Guatemala with significant thunderstorm activity, emerging into the Gulf of Tehuantepec around noon on May 29. By May 31, it was organized enough to be considered a tropical depression. Weakening on June 1 as it remained quasi-stationary, the system dissipated in the Gulf of Tehuantepec on June 4; this cyclone formed well to the west-southwest of Mexico on June 12. The depression recurved due to an upper level low located well to its north-northwest. By June 15, vertical wind shear had taken its toll and the system dissipated about 300 mi north of where it formed.
On June 15, this cyclone formed about 460 mi southwest of Acapulco. Drifting west-northwest, it strengthened into a tropical storm. Maximum sustained winds peaked near 50 mph late on June 15. Turning south of due west, vertical wind shear weakened Bud, with the cyclone dissipating by the morning of June 17 about 23 mi north-northwest of Clipperton Island. Late on June 16, deep convection organized in the Gulf of Tehuantepec into a tropical depression. Transcribing a small clockwise loop, the system moved west-northwest. Interaction with Mexico played a role in its weakening as water temperatures under the system were never below 82 °F; the system dissipated about 90 mi south of Puerto Ángel by the morning of June 19. A tropical wave crossed Central America on June 26, creating an area of thunderstorms just inside the tropical eastern Pacific that morning. Cyclonic turning was evident by the night of June 30 while located 350 mi south of Manzanillo as the system continued westward. Turning northwest, the system was upgraded to a tropical depression early on July 1 and a tropical storm by nightfall.
Maximum sustained winds increased to 60 mph by noon July 3. Southwest flow aloft turned Carlotta more northward into cooler waters, causing the cyclone to regain tropical depression status on the evening