SAN JUAN, PUERTO RICO, USA
23 TO 26 APRIL 2016
REVIEW OF THE PAST HURRICANE SEASON SUMMARY OF THE PAST SEASON 2015 Atlantic and Eastern North Pacific Hurricane Season Summary (Submitted by the RSMC Miami)
2015 Atlantic and Eastern North Pacific Hurricane Season Summary
1 Atlantic Tropical cyclone activity in the Atlantic basin during the 2015 season was below average. Of the 11 tropical storms that formed, 4 became hurricanes, and 2 reached major hurricane strength (category 3 or higher on the Saffir-Simpson Hurricane Wind Scale). In comparison, the 1981-2010 averages are 12 tropical storms, 6 hurricanes and 3 major hurricanes. The Accumulated Cyclone Energy (ACE) index, a measure that takes into account the strength, duration, and frequency of the season’s tropical storms and hurricanes, was 68% of the long-term median value. Most of the season’s tropical cyclones occurred well east of the United States, although Tropical Storm Ana made landfall in South Carolina and Tropical Storm Bill made landfall along the central Texas coast. In addition, Hurricane Joaquin battered the southeastern and central Bahamas as a category 4 hurricane, and was the strongest October hurricane known to have affected the Bahamas since 1866. Figure 1 depicts the tracks of the tropical storms and hurricanes of the 2015 Atlantic hurricane season.
Tropical Storm Ana A non-tropical low pressure system formed early on May 6 just offshore of the southeastern coast of Florida and moved slowly northward over the next two days, gradually developing an associated area of gales. On May 8, the low acquired sufficient thunderstorm activity for the system to be designated a subtropical storm when it was located about 175 miles south-southeast of Myrtle Beach, South Carolina. Ana moved slowly north-northwestward over the warm waters of the Gulf Stream on May 8-9 and transitioned to a tropical storm early on May 9 about 130 miles southeast of Myrtle Beach. Ana’s intensity remained steady near 60 mph while the cyclone was over the Gulf Stream. However, by late that day, the tropical storm began to weaken as it moved off of the Gulf Stream and over the cooler coastal shelf waters. Moderate to strong vertical wind shear enhanced the weakening process, and Ana made landfall around 1000 UTC May 10 just southwest of North Myrtle Beach, South Carolina, with an intensity of 45 mph. The May 10 landfall makes Ana the earliest United States. landfalling tropical cyclone on record.
Shortly after making landfall, Ana slowed and turned northward and weakened to a tropical depression. On May 11 the cyclone turned northeastward and moved across eastern North Carolina, degenerating to a remnant low pressure area before emerging off of the United States mid-Atlantic coast near the Delmarva Peninsula by May 12. The low merged with a frontal system near Nova Scotia on
Ana produced storm surge flooding up to 2.5 feet above normal tide levels along portions of the coasts of South Carolina and North Carolina. Storm-total rainfall of 3 to 6 inches occurred across portions of eastern North Carolina, producing some inland freshwater flooding. Abnormally high tides in combination with Ana’s storm surge resulted in minor beach erosion along the coasts of northeastern South Carolina and southeastern North Carolina. Property damage in the United States was minor.
There was one direct death associated with rip currents off the coast of North Carolina.
Tropical Storm Bill Bill formed from the complex interaction of an upper-level trough over the Gulf of Mexico, a broad area of low pressure near the Yucatan Peninsula, and southerly winds associated with eastern North Pacific Hurricane Carlos. The combination of these three features resulted in a broad disturbance forming over northern Belize and the Yucatan Peninsula on June 13, which became a tropical storm on June 16 while centered about 200 miles east-southeast of Corpus Christi, Texas. Bill continued northwestward during most of June 16, but slowed down and turned west-northwestward as it approached the Texas coast. Bill made landfall on Matagorda Island at 1645 UTC June 16 with maximum winds of 60 mph. Later that evening, Bill turned northward and accelerated inland over eastern Texas, weakening to a tropical depression early on June 17 when centered about 35 miles east of Austin, Texas. The depression continued northward for the next two days, and became a remnant low on June 18 while located about 75 miles south-southeast of Tulsa, Oklahoma. Bill’s remnant low moved eastnortheastward for the next few days, producing heavy rain, flooding, and tornadoes across southern Missouri, northern Arkansas, and portions of the Ohio River Valley.
The low dissipated on June 21 over the mountainous terrain of West Virginia.
Bill produced a storm surge of 3.5 feet just east of its landfall point. Combined with the normal tide, Bill’s surge produced inundation of 1 to 3 feet above ground level for parts of the upper Texas and southwestern Louisiana coasts.
Heavy rains from Bill also fell from the central Texas coast northeastward across eastern Texas, western Louisiana, and southern and eastern Oklahoma. Many locations reported storm-total amounts in excess of 10 inches with the highest rainfall report being 13.78 inches in Ganado, Texas. The heavy rainfall caused flash floods and flooding of major rivers across portions of Texas and Oklahoma. The Red River at Interstate 35 along the Texas/Oklahoma border reached a record crest of 42.05 feet, 17 feet above flood stage. Farther north, the Washita River near Dickson, Oklahoma, reached a record crest of 48.70 feet, which was more than 21 feet above flood stage. Flash flooding was reported in the Austin and San Antonio metro areas. Property damage in the United States was minor.
Bill caused two direct deaths as a result of heavy rain and flooding in Oklahoma during its tropical depression stage. In addition, Bill’s precursor disturbance produced heavy rains, flooding, and landslides over portions of Central America and the Yucatan Peninsula of Mexico. In Honduras, two people died in floodwaters near Tegucigalpa, while two other people were reported missing. More than 500 people were affected by floods and landslides in Honduras. Two people died in landslides in Guatemala, with 516,000 people having been affected by flooding and landslides in that country.
Tropical Storm Claudette Claudette developed from a non-tropical surface low associated with a midlevel trough that formed near Cape Hatteras on July 12. The low moved eastward for the next 24 hours over the warm waters of the Gulf Stream and, early on July 13, the low became a tropical depression. The system was sheared, thunderstorm activity displaced to the northeast of the circulation center. However, the cyclone became a tropical storm by early July 13, and reached its peak intensity of 50 mph later that day about halfway between Bermuda and Cape Cod. Claudette then moved toward the northeast over the colder waters of the North Atlantic, where strong vertical wind shear gradually separated the center from the intermittent thunderstorm activity, and the cyclone degenerated to a remnant low, which was quickly absorbed by a frontal system near Newfoundland.
Hurricane Danny Danny developed from a vigorous tropical wave that moved off of the coast of western Africa on August 14. A tropical depression formed on August 18 and strengthened into a tropical storm later that day about 1600 miles east of the Windward Islands. Danny moved generally westward across the eastern and central tropical Atlantic over the next several days and steadily strengthened, becoming a hurricane on August 20 when the cyclone was located about 1090 miles east of the Windward Islands. A period of significant strengthening began immediately after Danny achieved hurricane status, and the cyclone rapidly became a 125-mph major hurricane by mid-day August 21. However, Danny’s rapid development was cut short by intrusions of dry air and increasing vertical wind shear, which caused the cyclone to weaken as quickly as it had strengthened. Danny became a tropical storm on August 23 and a tropical depression on August 24 when the cyclone was moving through the central and southern Leeward Islands. Danny degenerated into an open wave when the system moved into the extreme northeastern Caribbean Sea. The remnants of Danny moved westward across the northern Leeward Islands, the Virgin Islands, Puerto Rico, and Hispaniola for the next day or so, bringing short-lived but beneficial rains to those drought-stricken islands.
Tropical Storm Erika Erika developed from a fast-moving wave, bypassing the tropical depression stage, and became a 45-mph tropical storm on August 24 while centered about 950 miles east of the Lesser Antilles. The cyclone continued westward at a brisk pace, reaching the northern tip of Guadeloupe by early August 27. Erika moved over the northeastern Caribbean Sea August 28, passing south of the United States. Virgin Islands and Puerto Rico. Later that day, Hurricane Hunter aircraft observations revealed that Erika no longer had a well-defined center of circulation, and the tropical cyclone dissipated just south of the eastern tip of Hispaniola.
The largest rainfall amounts associated with Erika were observed on Dominica, where maximum totals reached 12.62 inches. Practically all of this precipitation occurred during a 12-hour period on August 27, and these torrential rains produced catastrophic flooding and mudslides over the island. Erika was responsible for 30 direct deaths, all in Dominica. Also, 574 persons on that island were made homeless by the storm and 271 houses were reportedly damaged or destroyed. There was also major damage to roads, bridges and other infrastructure on the island, with the total damage estimated near US $ 500 million. Damage estimated near $17.4 million also occurred in Puerto Rico, mainly due to losses of plantains, bananas, and coffee.
Hurricane Fred Fred was the first hurricane to move through Cabo Verde since 1892. It formed from a tropical wave that emerged from the west coast of Africa early on August 29 and uncharacteristically began to develop just west of the coast of Guinea later that day, with a tropical depression forming early on August 30 about 300 miles west northwest of Conakry, Guinea. The depression moved quickly on an atypical northwestward track toward Cabo Verde. The combination of above-average sea surface temperatures and light vertical wind shear enabled rapid strengthening to occur and the cyclone reached tropical storm strength 6 hours after genesis, and became a hurricane by August 31 about 165 miles south-southeast of Sal, Cabo Verde. Fred moved through the islands later that day, reaching a peak intensity of 85 mph. After that, a combination of decreasing sea-surface temperatures and increasing southwesterly shear caused weakening, and Fred weakened to a tropical storm early on September 1 as it moved away from Cabo Verde. Fred moved west-northwestward to westward over the next few days, while gradually weakening. Fred turned northward on September 6 and degenerated into a trough about 1200 miles southwest of the Azores.
Storm surge and high surf affected several islands of Cabo Verde. It is estimated that 6 to 8 inches of rain occurred on several of the Cabo Verde islands. These rains caused some flooding, but also filled reservoirs that were low due to drought. Fred caused 9 direct deaths. The Greek-registered fishing boat Dimitrios sank off the coast of Guinea-Bissau due to the high waves generated by Fred, and 7 members of its crew of 19 were not found. In addition, two fishermen from Cabo Verde were reported missing and presumed dead when their fishing boat failed to return to the island of Boa Vista. Fred caused about US $1 million damage on several islands of Cabo Verde, with Boa Vista being the hardest hit. Additional damage from rough surf and above-normal tides occurred along the coast of Africa, with damage to crops reported in Guinea-Bissau due to salt water inundation.
Tropical Storm Grace Grace formed from a well-organized tropical wave that left the coast of western Africa on September 3. It developed into a tropical depression on September 5 about 170 miles south of Cabo Verde, and 12 hours later became a tropical storm. Grace gradually strengthened over the next couple of days, reaching an estimated intensity of 60 mph by mid-day September 6. The cyclone then moved into unfavorable environmental conditions and weakened. Grace decayed to a tropical depression on September 8 and degenerated to a trough on September 9 about
750 miles east of the Lesser Antilles. The remnants of Grace brought gusty winds and heavy rains to the northeastern Leeward Islands and Puerto Rico a couple of days later.
Tropical Storm Henri Henri’s origin was non-tropical, resulting from a dissipating frontal boundary interacting with an upper-level trough over the western Atlantic. A surface low developed along the weakening front early on September 8 and became a tropical depression by late that day about 220 miles east-southeast of Bermuda. The depression intensified into a tropical storm on September 9 and reached a peak intensity of 50 mph late that day when it turned northward ahead of an upper-level trough. By early September 11, Henri’s circulation became distorted, and the cyclone degenerated into a trough later that day more than 500 miles south-southwest of Cape Race, Newfoundland.
Tropical Storm Ida The genesis of Ida was associated with a tropical wave that spawned a tropical depression on September 18 more than 700 miles west of the southernmost Cape Verde Islands. The depression moved west-northwestward and strengthened into a tropical storm by early September 19. Westerly vertical wind shear inhibited development, and Ida reached its maximum intensity of 50 mph early on September 21, when the cyclone was located about 1000 miles east of the northern Leeward Islands. The shear steadily increased on September 21, causing Ida to slowly weaken. Over the next few days, Ida meandered in weak steering currents, and it eventually dissipated on September 28 about 860 miles east-northeast of the northern Leeward Islands.
Hurricane Joaquin Joaquin did not have tropical origins, which is rare for a major hurricane. The incipient disturbance developed beneath a weak mid- to upper-level low over the subtropical central Atlantic on September 26 about 400 miles east-northeast of San Salvador Island in the central Bahamas, and a tropical depression formed two days later. Moderate north-northwesterly shear prevented the depression from strengthening initially, but the cyclone became a tropical storm early on September 29 while centered about 340 miles northeast of San Salvador.
A blocking ridge of high pressure located over the western Atlantic forced Joaquin to move slowly southwestward over very warm waters near the Bahamas. A 60hour period of rapid intensification began on September 29, and Joaquin became a hurricane on September 30 about 200 miles east-northeast of San Salvador, and then a major hurricane on October 1 about 100 miles east of San Salvador. Sea-surface temperatures in the area where Joaquin formed and rapidly intensified were more than 1°C higher than normal, and were the warmest on record for the period September 1827.
A mid- to upper-level trough over the eastern United States deepened on October 1-2, causing the hurricane to slow down as it approached the southeastern and central Bahamas. Joaquin continued to strengthen, reaching a relative peak in intensity as a 140-mph category 4 hurricane early on October 2. The powerful cyclone made landfall as a major hurricane on several islands of the Bahamas
on October 1-2, first on Samana Cay in the morning of October 1, then on Rum Cay and San Salvador during the afternoon of 2 October. In addition, Joaquin’s eyewall moved over Crooked Island, Long Cay, and Long Island. Even though it weakened slightly on October 2, Joaquin was a major hurricane the entire time that it moved through the southeastern and central Bahamas, and it was the strongest October hurricane known to have affected the Bahamas since 1866.
By early October 3, Joaquin accelerated northeastward away from the Bahamas and re-intensified, reaching a peak intensity of 155 mph. The hurricane moved north-northeastward over the western Atlantic and weakened, but it was still a hurricane when the cyclone made its closest approach to Bermuda, about 70 miles west-northwest of the island early on October 5. Joaquin turned northeastward and east-northeastward on October 6-7 as it became embedded in the mid-latitude westerlies, where it weakened to a tropical storm early on October 7 while centered about 480 miles southeast of Cape Race, Newfoundland.
Strong west-southwesterly shear caused the cyclone to become post-tropical by October 8 about 440 miles west-northwest of the northwestern Azores. As an extratropical low, Joaquin moved eastward and southeastward over the northeastern Atlantic on October 9-12, with its center moving inland just north of Lisbon, Portugal, early on October 12. The low then turned southward, weakened below gale force, and moved back over the Atlantic waters off the coast of Portugal on October 13. The low ultimately dissipated by October 15 between Portugal and Morocco over the Gulf of Cádiz.
Joaquin produced storm surges of 12 to 15 feet on Rum Cay, Crooked Island, and Acklins. Some coastal flooding due to Joaquin also occurred in the Turks and Caicos Islands, Haiti, and Cuba, but no water level observations are available from those areas. Joaquin also contributed to indirect surge impacts along the United States east coast. Higher-than-normal tides, onshore gale-force winds behind a frontal boundary, and swells propagating away from Joaquin all contributed to storm surge flooding, with the worst flooding occurring in South Carolina, North Carolina, and Virginia. The highest storm surges reported were about 4 feet above normal tide levels in South Carolina and Virginia.
Joaquin produced 5 to 10 inches of rainfall in portions of the central and southeastern Bahamas. In addition, moisture transported away from Joaquin contributed to an historic rainfall and flooding event in South Carolina and parts of southern North Carolina. Rainfall amounts exceeding 15 inches occurred in a swath extending from the South Carolina Lowcountry northwestward through the Midlands, as well as along the coast near the North Carolina/South Carolina border. In the Lowcountry, rainfall amounts greater than 20 inches occurred in Charleston and Berkeley Counties, with a maximum rainfall amount of 26.88 inches measured near Mt. Pleasant. One-, two-, three-, and four-day rainfall records were set at the Charleston International Airport. The airport measured a one-day rainfall amount of 11.50 inches on October 3 and a four-day total of 17.29 inches during October 1-4. In the Midlands, rainfall amounts greater than 20 inches occurred in Richland, Sumter, and Orangeburg Counties. One-, two-, and threeday rainfall records were also set at the Columbia Metropolitan Airport, with 6.71 inches measured on October 4 and 11.44 inches for the entire event. In North Carolina, a maximum rainfall amount of 18.79 inches was reported near Sunset Beach in Brunswick County.
Joaquin is directly responsible for 34 deaths in the waters off the Bahamas and Haiti. Almost all of the deaths occurred when the U.S.-flagged cargo ship
El Faro was lost at sea near the Bahamas while Joaquin was moving through the area. The Caribbean Disaster Emergency Management Agency (CDEMA) reported that a fisherman in his 30s drowned when his and another fisherman’s boat capsized in rough seas off the coast of Haiti between Petit-Trou-de-Nippes and Grand Boucan.
The prime minister of the Bahamas and the Bahamas Department of Meteorology estimated the damage caused by Joaquin was well over US $ 60 million. Seventy percent of Crooked Island was flooded with at least 5 feet of water. The entire island lost power, and there was significant damage to buildings and homes. On Acklins, significant flooding was reported, with an estimated 20 homes destroyed. Power lines were downed, private fresh water wells were flooded, and structural damage occurred to homes on Long Island. Over two-thirds of the island remained inundated with 4-6 feet of water by October 7. On Rum Cay, severe flooding, downed trees, impassable roads, and downed power lines and poles were reported across the island. On San Salvador, flooding, downed power lines and poles, and significant damage to homes were reported throughout the island. Many roads were impassable, and the airport building was completely destroyed. Extreme flooding and downed power lines were reported on Exuma, but only minor damage to homes was reported on Mayaguana. Less extensive damage was reported in the Turks and Caicos Islands, northwestern Haiti, Bermuda, and in the Cuban province of Granma.
Hurricane Kate The development of Kate was associated with a tropical wave that spawned a tropical depression on November 8 just to the north of the Turks and Caicos Islands. Although such development so late in the season is rare, it is not unprecedented. The depression became a tropical storm the next day near the central Bahamas while it moved toward the northwest and north, with its center passing just to the east of the northwestern Bahamas late that day. The small cyclone moved northward around the periphery of the Bermuda-Azores subtropical high and steadily intensified. After recurving into the mid-latitudes, Kate reached hurricane status by November 11, with its peak intensity of 85 mph occurring later that day. After that time, the hurricane encountered strong westerly shear and cold waters, and transformed into an extratropical cyclone by November 12. The powerful low continued to move eastward until late November 13, when it was absorbed by a larger extratropical cyclone over the north Atlantic.
Table 1. 2015 Atlantic hurricane season statistics.
Max. Winds (kt)
Min. Pressure (mb)
U.S. Damage ($million)
8 – 11 May
16 – 18 June
13 – 14 July
18 – 24 August
24 – 28 August
30 August – 6 September
5 – 9 September
8 – 11 September
16 – 19 September
18 – 27 September
28 September – 7 October
8 – 11 November
a) Tropical depression (TD), maximum sustained winds 33 kt or less; tropical storm (TS), winds 34-63 kt; hurricane (H), winds 64-95 kt; major hurricane (MH), winds 96 kt or higher.
b) Dates begin at 0000 UTC and include all tropical and subtropical cyclone stages; non-tropical stages are excluded.
Figure . Tracks of the Atlantic tropical storms and hurricanes of 2015.
2 Eastern North Pacific The 2015 eastern North Pacific hurricane season was very active. Of the 18 cyclones that reached tropical storm strength, 13 became hurricanes and 9 reached major hurricane status (category 3 or higher on the Saffir-Simpson Hurricane Wind Scale). The number of major observed in 2015 was the highest since reliable records began in 1971. For comparison, the 1981-2010 seasonal averages are 15 tropical storms, 8 hurricanes and 4 major hurricanes. The Accumulated Cyclone Energy (ACE), which measures the combined strength and duration of tropical storms and hurricanes was about 63 percent higher than the 1981-2010 median value. This ACE value is the highest observed in the basin since 1993. There were three unnamed tropical depressions, and another one that formed in the basin and became a tropical storm (Ela) in the central North Pacific.
The genesis of most of the tropical cyclones was associated with tropical waves that moved westward from the Atlantic to the eastern North Pacific basin. While strong westerly shear in the eastern part of the basin prevented most of these waves from developing there, the western part of the basin had much lower shear than average and the ocean was anomalously warm. A large area of an upper-level diffluence and rising motion persisted during most of the active portion of the 2015 season (Fig.1). These very favorable conditions for genesis and intensification are usually present in the basin during strong El Nino events, although the activity was shifted even farther west than expected during those events.
Most of the cyclones intensified and moved away from Mexico. Despite the above average season, record-breaking Patricia was the only hurricane to make landfall in Mexico during 2015. Hurricane Patricia, which was the strongest hurricane on record in the eastern North Pacific basin, weakened to category 4 strength on the SaffirSimpson Hurricane Wind Scale before it made landfall near Playa Cuixmala, about 50 miles west-northwest of Manzanillo. Moisture from several tropical cyclones spread northward causing locally heavy rainfall over portions of northern Mexico and the southwestern United States during the season. Table 1 lists the tropical cyclones of the 2015 season, and the tracks of the season’s tropical storms and hurricanes are shown in Figures 2a and 2b.
Hurricane Andres A tropical depression formed early on May 28 about 825 miles south of the southern tip of the Baja California peninsula, and became a tropical storm later that day. Andres moved west-northwestward and then northwestward, reaching hurricane strength about 775 miles south-southwest of the southern tip of the Baja California peninsula on May 29. A period of rapid intensification then began, and the hurricane reached its peak intensity of 145 mph early on June 1. Weakening occurred quickly as the cyclone moved west-northwestward over cooler waters.
Hurricane Blanca Blanca formed on May 31 about 390 miles south-southwest of Acapulco. The cyclone initially moved west-northwestward to northwestward and was affected by strong northwesterly wind shear associated with the outflow of Hurricane Andres to its west. The shear relaxed and the system was able to strengthen while it drifted erratically within poorly defined steering currents. Blanca became a major hurricane with a pinhole eye on June 3, and reached its peak intensity of 145 mph later that day about 470 miles south of Manzanillo. Due to the upwelling of cooler waters, the cyclone weakened, but as Blanca moved away from its cold wake it temporarily re-intensified. The maximum winds had diminished to near 45 mph by the time Blanca made landfall on the west coast of Baja California Sur early on June 8. Later that day, the center of the cyclone moved briefly over water to the west of Baja California Sur and then made its final landfall on the west coast of that state. Moisture associated with Blanca’s remnants produced mostly light rains over portions of the southwestern United States. Rainfall totals were mostly less than an inch, with higher amounts at some of the more elevated areas.
Hurricane Carlos Carlos began as a tropical depression on June 10 about 290 miles southsouthwest of Puerto Escondido. Despite moderate shear, the system reached tropical storm intensity on the 11th about 230 miles south of Acapulco, and became a hurricane two days later while moving parallel to the southern coast of Mexico. Data from an Air Force Reconnaissance plane indicated that Carlos attained its peak intensity of 90 mph around midday June 16, about 105 miles south of Manzanillo. Only 6 h after the cyclone attained its peak intensity, the surface center separated from the deep convection and Carlos rapidly decayed. The cyclone made landfall in Mexico near Tenacatita with 50-mph winds and then dissipated in the vicinity of the Islas Marias.
Carlos caused locally heavy rains over portions of southern and western Mexico from 11-19 June. The heaviest amounts occurred in the state of Oaxaca with Union Hildago reporting 11.97 inches and Chicapa 10.83 inches. La Jornada, a Mexico City newspaper, reported that high surf generated by Carlos damaged a few dozen boats and sank several boats in Acapulco, while strong winds knocked down trees and billboards. According to the news site MiMorelia.com, large waves and heavy rain caused at least US $326,000 in damage to coastal structures near Lazaro Cardenas.
Hurricane Dolores A surface low pressure system developed about 345 miles south-southwest of Salina Cruz on July 10, and although southerly shear was affecting the disturbance, a tropical depression formed early July 11 about 345 miles south-southeast of Acapulco. The depression intensified while it moved parallel, but far enough off of the southwestern coast of Mexico to keep winds of tropical storm force offshore. Dolores moved away from the coast and became a hurricane late on July 13 about 165 miles south-southwest of Manzanillo, and reached its peak intensity of 130 mph on the June 15. A slow weakening occurred while the hurricane was passing not too far from Socorro Island late that day, where sustained 80-mph winds with gusts to 115 mph were observed. The cyclone weakened over cool waters and dissipated early on June 22 a few hundred miles west-southwest of San Diego, California. Moisture associated with the remnants of the cyclone produced very rare July heavy rains over portions of southern California.
Tropical Storm Enrique The tropical depression that became Enrique formed from a broad area of low pressure on July 12 about 1200 miles west-southwest of the southern tip of the Baja California peninsula. The cyclone moved slowly north-northwestward, reaching its peak intensity of 50 mph on the 14th. Early the next day, increasing south-southwesterly vertical wind shear caused the circulation to become tilted and the tropical cyclone weakened. Enrique degenerated to a remnant low about 1600 miles west of the southern tip of the Baja California peninsula on July 18, and dissipated on July 22.
Tropical Storm Felicia Short-lived Felicia formed on July 23, about 430 miles southwest of the southern tip of the Baja California peninsula and became a 40-mph tropical storm 6 h later. As the cyclone moved northwestward, strong shear caused the storm to weaken, and the cyclone degenerated into a remnant low on the 24th about 545 miles west of the southern tip of the Baja California peninsula.
Hurricane Guillermo An area of low pressure formed near 6˚N south of the Baja California peninsula the morning of July 27. Over the next two days, cyclonically curved rainbands developed, marking the formation of a tropical depression on July 29 about 1300 miles southwest of the southern tip of the Baja California peninsula. The depression moved west-northwestward into a very favorable environment and became a tropical storm on July 30 and a hurricane the next day. The strengthening process continued, and Guillermo, with a distinct eye, reached its peak intensity of 110 mph. After that time, weakening occurred, but the hurricane maintained winds of 105 mph while moving west-northwestward into the Central Pacific Hurricane Center’s area of responsibility. Guillermo passed just to the north of the Hawaiian Islands as a weakening cyclone and produced unusually large surf of up to 15 feet on east-facing shores, sending water and debris over roads on August 6.
Hurricane Hilda Hurricane Hilda developed from a small but well-defined area of low pressure late on August 5 about 1500 miles west-southwest of Cabo San Lucas and rapidly became a tropical storm. With a very small inner core, the cyclone strengthened, and satellite intensity estimates indicated that Hilda reached its peak intensity of 140 mph on 8 August just before moving into the central Pacific basin well south of the Hawaiian Islands, where it gradually weakened.
Hurricane Ignacio A low pressure area led to the formation of a tropical depression on August 25 about 1500 miles west-southwest of the southern tip of the Baja California peninsula. Moving westward and west-southwestward on the south side of the subtropical ridge, the depression became a tropical storm on August 25 and a hurricane the next day. Ignacio turned west-northwestward and moved into the Central Pacific basin on August 27 with maximum winds of 90 mph. Once over the central Pacific, the hurricane reached its peak intensity of 145 mph early on August 30 about 500 miles east-southeast of Hilo, before it merged with a cold front and dissipated south of the Aleutian Islands.
Very large and powerful surf of up to 20 feet, heights rarely seen on the east sides of the Hawaiian Islands, washed up sand and debris on windward coastal highways throughout the state on September 1. Deep tropical moisture associated with the outer circulation of Ignacio caused major flash flooding in downtown Honolulu on September 3 causing considerable damage to businesses and automobiles.
Hurricane Jimena Jimena, which rapidly deepened to its peak intensity of 155 mph – just below category 5 status on the Saffir-Simpson Hurricane Wind Scale early on August 29, formed from a broad low pressure area that became a tropical depression a few days earlier about 740 miles southwest of Manzanillo. Jimena experienced a period of explosive strengthening, when the hurricane was located about 1200 miles southwest of the southern tip of Baja California. Shortly after reaching its peak intensity, however, an eyewall replacement cycle occurred and a weakening trend began. Jimena continued west-northwestward as it moved into the Central Pacific hurricane basin early on September 1, and dissipated about 200 miles north of the Hawaiian Islands on September 10. Immediately on the heels of Ignacio, Jimena sent a second very large and persistent east swell with waves up to 20 feet to the east shores of the islands from September 4 through September 6.
Tropical Storm Kevin An elongated area of low pressure centered at relatively low latitude became a tropical depression about 750 miles south of the southern tip of the Baja California peninsula on August 30. During the next couple of days, the cyclone moved northwestward and reached tropical storm strength on September 1 about 725 miles south-southwest of the southern tip of Baja California. A microwave pass over the cyclone showed a mid-level eye late on September 3, suggesting the potential for strengthening, but Kevin’s mid-level circulation separated from the low-level center, and on the 5th, Kevin became a remnant low.
Hurricane Linda On September 2, despite a prevailing moderate northeasterly shear, a broad area of low pressure led to the formation of a tropical depression on September 5, about 490 miles southwest of Manzanillo. The cyclone became a tropical storm early the next day and reached hurricane status several hours later. The center of the intensifying cyclone passed midway between Socorro and Clarion Islands with a distinct eye, and on September 8, Linda reached its peak intensity of 125 mph before moving over cooler waters and degenerating into a post-tropical cyclone.
Moisture partially originating from Linda spread northward, causing locally heavy rainfall over portions of the southwestern United States. On 15 September, a strong mid- to upper-level trough and the remnants of Linda moved eastward into southern California producing 2.39 inches of rain in Los Angeles on that day. This was the second-wettest September day since records began in that city in 1877.
A rainfall total of 1.15 inches was observed in San Diego that same day, which was also that city’s second-wettest September day on record.
Linda and its remnants caused no casualties or damage in either Mexico or the United States. Media reports, however, indicate that 7 hikers died in a narrow canyon in Utah’s Zion National Park when it filled with rushing water during the flash flood. That same day, 12 other people, including nine children, died in Hildale, Utah, when two vehicles were swept away in flash flooding. A 6-year old child in one of the vehicles remains missing and is presumed to have perished. The 20 fatalities that occurred in Utah that day makes it the deadliest flood event in the state’s history. These are not considered direct deaths caused by the tropical cyclone.
Hurricane Marty Marty began as a tropical depression on September 26 about 340 miles southwest of Acapulco, and strengthened into a tropical storm on September
27while moving northward. Despite the prevailing shear, Marty became a hurricane about 220 miles west of Acapulco, and data from an Air Force Reserve reconnaissance flight indicate that the hurricane reached a peak intensity of 80 mph. Under the influence of a trough to the northwest, the cyclone slowly turned northeastward toward the coast, but strong shear caused weakening, and Marty degenerated into a post-tropical low early on September 30 about 140 miles west-southwest of Acapulco.
Tropical-storm-force winds remained offshore of the southwestern coast of Mexico, but rains from Marty flooded three hundred homes west of Acapulco in the vicinity of Río Coyuca.
Tropical Storm Nora A tropical depression formed on October 9 about 1850 miles east-southeast of the Hawaiian Islands, and became a tropical storm later that day. Nora moved west and west-northwest into the Central Pacific Hurricane Center’s area of responsibility on October 11 with 70- mph winds. The cyclone encountered a hostile environment in the central Pacific and dissipated on the 15th well to southwest of the Hawaiian Islands. Nora’s remnants, however, brought heavy rainfall to the windward sections of the state from the Big Island to Oahu. Rainfall of 3 to 6 inches produced significant runoff that closed a major highway north of Hilo on the Big Island.
Hurricane Olaf Increasing convection associated with a low pressure area led to the formation of a tropical depression on October 15 about 990 miles south-southwest of Cabo San Lucas. The depression strengthened into a tropical storm about 48 h later, and Olaf became a hurricane at 9°N, unusually low latitude. The hurricane moved into the central Pacific basin, and reached its peak intensity of 150 mph early on October 20. Steadily weakening occurred over the next few days, when a strong upper-level trough approached from the northwest, causing increased vertical wind shear and forcing the cyclone to recurve back into the eastern North Pacific. Olaf degenerated into a trough on October 28.
Hurricane Olaf produced unusually high east-shore surf as it passed well to the east of the islands during October 21 through 26. Surf heights up to 20 feet were reported on the Big Island, and the large waves caused coastal flooding of a highway south of Hilo on October 22.
Hurricane Patricia Patricia, the strongest hurricane on record in the eastern North Pacific, and the strongest hurricane on record to affect Mexico, had a slow and complicated genesis involving the interaction of multiple weather systems. It began as an elongated area of low pressure that extended from the Yucatan Peninsula southward for several hundred miles into the eastern Pacific on October 16. Deep convection associated with this system increased, and a tropical depression formed on October 20 about 200 miles south-southeast of Salina Cruz.
The depression drifted west-southwestward while it gradually strengthened. By the time a NOAA Hurricane Hunter aircraft reached the cyclone on October 21, Patricia already had reached an intensity of 60-mph. Patricia strengthened into a hurricane later that day about 230 miles south of Acapulco. By October 22, a NOAA plane indicated that Patricia’s intensity had reached 130 mph and a minimum pressure of 957 mb. The rapid intensification phase continued into the night while Patricia turned northwestward and slowed down. By the time an Air Force Hurricane Hunter aircraft reached the cyclone around midnight, Patricia had intensified into an extremely powerful hurricane with maximum sustained winds of 205 mph and a minimum central pressure of around 879 mb. The cloud pattern continued to increase in organization over the next several hours after the plane left, and the hurricane reached a peak intensity of 215 mph in the morning of the 23rd about 150 miles southwest of Manzanillo. This intensity makes Patricia the strongest hurricane on record in the eastern North Pacific; it should be noted, however, that records for the most intense eastern North Pacific hurricanes are particularly uncertain prior to 1988.
Patricia turned north-northwestward and then northward toward the coast of Mexico while essentially maintaining its intensity. By the time the last reconnaissance mission reached Patricia in the afternoon of October 23, the surface winds were still near 205 mph, but a final pass by the plane a few hours later indicated that a rapid filling of the cyclone had begun. In fact, the peak flight-level winds had decreased nearly 50 kt in the same quadrant traversed earlier, while the central pressure had risen 24 mb in the 3 h since the first fix.
Patricia made landfall in the state of Jalisco, near Playa Cuixmala, late on October 23 with an intensity of 150 mph and a minimum pressure of around 932 mb, the lowest central pressure for a landfalling Pacific hurricane in Mexico in the historical database. A minimum pressure of 934.2 mb was observed late on the 23rd by an automated weather station at Playa Cuixmala while a storm chaser in Emiliano Zapata, a couple of nautical miles inland from the landfall point, measured a minimum pressure of 937.8 mb on the eastern edge of the eye. The hurricane weakened rapidly during the next several hours while it moved over the high terrain of the Sierra Madre where it dissipated.
Patricia is the strongest hurricane on record to affect Mexico in the historical data base extending back to 1949. Because of the sparse nature of station observations over Mexico, however, the reliable record for extreme landfalling Mexican hurricanes is also tied to the availability and interpretation of satellite imagery of these systems, and is thought to be reliable only back to 1988.
A sparsely populated area of the southwestern coast of Mexico in Jalisco, nearly midway between Manzanillo and Puerto Vallarta was battered by the hurricane. A joint survey conducted by CONAGUA and the United States National Weather Service after the storm indicated that Patricia produced a narrow swath of severe damage along and just inland from the coast near where the hurricane made landfall. The villages of Emiliano Zapata and Chamela sustained the worst damage, according to press reports and eyewitness accounts. Large swells associated with Patricia caused significant coastal flooding for several days that resulted in beach erosion and damage to some structures in the Mexican states from Jalisco to Guerrero. According to media reports, the preliminary damage from Patricia is estimated to be $325 million (USD).
Rainfall accumulations of about 8 to 13 inches occurred over mountainous terrain, with Nevado Colima in Jalisco reporting a storm total rainfall of 12.50 inches. Press reports indicate that there were two direct deaths attributed to Patricia. Two women, one from Argentina and the other from Coahuila, Mexico, were crushed when a tree fell on them at a campsite in the Tapalpa forest in Jalisco. There were four indirect deaths associated with the storm, when four passengers were killed in an automobile accident on the Colima-Guadalajara highway during heavy rains and strong winds associated with the storm.
Tropical Storm Rick A tropical depression formed on November 18 about 715 miles southsoutheast of the southern tip of the Baja California Peninsula, and as the shear decreased, the cyclone strengthened to a tropical storm with an estimated peak intensity of 40 mph the next day. The cyclone moved general west-northwestward, but encountered dry air that prevented any additional strengthening. Rick remained a tropical storm until November 22 when the associated convection dissipated and the cyclone became a remnant low.
Hurricane Sandra Sandra, the latest-forming major hurricane in the eastern North Pacific basin during the satellite era, originated from a broad low pressure area south of Mexico, and became a tropical depression on November 23 about 575 miles south-southwest of Acapulco. The depression moved west-northwestward and strengthened, becoming a tropical storm about 575 miles south of Manzanillo. An eye feature with a diameter of 25-30 miles developed on November 24, initiating a period of rapid intensification. During the next 36 h, the cyclone strengthened significantly, reaching its peak intensity of 150 mph early on November 26. Increasing southwesterly vertical wind shear became established and the cyclone degenerated into a trough of low pressure about 60 miles southwest of Culiacán. Culiacán.
3 Forecast Verification. For all operationally designated tropical or subtropical cyclones in the Atlantic and eastern North Pacific basins, the National Hurricane Center (NHC) issues an “official” forecast of the cyclone’s center location and maximum 1-min surface wind speed. Forecasts are issued every 6 h, and contain projections valid 12, 24, 36, 48, 72, 96, and 120 h after the forecast’s nominal initial time (0000, 0600, 1200, or 1800 UTC) At the conclusion of the season, forecasts are evaluated by comparing the projected positions and intensities to the corresponding post-storm derived “best track” positions and intensities for each cyclone. A forecast is included in the verification only if the system is classified in the final best track as a tropical (or subtropical cyclone at both the forecast’s initial time and at the projection’s valid time. All other stages of development (e.g., tropical wave, [remnant] low, extratropical) are excluded. For verification purposes, forecasts associated with special advisories do not supersede the original forecast issued for that synoptic time; rather, the original forecast is retained. All verifications in this report include the depression stage. The 2015 official forecast errors for the Atlantic and Eastern North Pacific are included in Figures 5 and 6, respectively.
The cyclone summaries are based on Tropical Cyclone Reports prepared by the RSMC Hurricane Specialist Unit. These reports are available on the Internet at http://www.nhc.noaa.gov/data/tcr/index.php?season=2015&basin=atl
Table 2. 2015 eastern North Pacific hurricane season statistics.
Max. Winds (kt)
Min. Pressure (mb)
U.S. Damage ($million)
May 28 –June 4
May 31- June 9
July 29- Aug 7
August 25- September 5
August 26–September 9
August 31- September 5
a Tropical depression (TD), maximum sustained winds 33 kt or less; tropical storm (TS), winds 34-63 kt; hurricane (H), winds 64-95 kt; major hurricane (MH), winds 96 kt or higher.
b Dates begin at 0000 UTC and include all tropical and subtropical cyclone stages; non-tropical stages are excluded.
Peak intensity and minimum pressure was reached outside the eastern North Pacific hurricane basin.
Figure a. Tracks of the eastern north Pacific tropical storms and hurricanes of 2015.
Figure b. Tracks of the eastern north Pacific tropical storms and hurricanes of 2015.
Figure 5. 2015 RSMC Miami Official forecast verification for the Atlantic.
Figure 6. 2015 RSMC Miami Official forecast verification for the eastern North Pacific.