Review of the past hurricane season summary of the past season
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REVIEW OF THE PAST HURRICANE SEASON SUMMARY OF THE PAST SEASON 2012 Atlantic and Eastern North Pacific Hurricane Season Summary (Submitted by the RSMC Miami) 2013 Atlantic and eastern North Pacific Hurricane Season Summary (Submitted by RSMC Miami) ATLANTIC Despite seemingly conducive climate conditions, including much warmer than normal Atlantic water temperatures and the absence of El Niño, the 2013 Atlantic hurricane season was well below average overall. While the year had a slightly above-average number of named storms (14), only two of these storms became hurricanes (Figure 1 and Table 1). For the first time since 1994, no hurricane reached major hurricane (Category 3 or higher on the Saffir Simpson Hurricane Wind Scale) strength. The long-term (1981–2010) average numbers of hurricanes and major hurricanes are 6 and 3, respectively. As measured by the NOAA Accumulated Cyclone Energy (ACE) index, which considers the strength and duration of the (sub)tropical storms and hurricanes, the 2013 Atlantic season was the quietest season since 1994, with an ACE value of only 39% of the long-term median. No hurricanes and only one tropical storm, Andrea, made landfall in the United States, causing one fatality. While most of the basin experienced below-average activity, Mexico was hit hard by Tropical Storms Barry, Fernand and Ingrid. These storms caused devastating flooding and over 30 deaths in that country. Tropical Depression Eight also made landfall in Mexico, but any impacts were minor. 4.1.1 Tropical Storm Andrea Andrea had a complex origin involving the remnants of eastern Pacific Hurricane Barbara, a tropical wave, and a large and persistent cyclonic gyre that formed over southeastern Mexico and northern Central America. All of these factors led to the formation of a broad area of low pressure over the southern Gulf of Mexico on June 3. When moderate shear decreased somewhat on June 5, a tropical storm formed late that day a few hundred miles southwest of St. Petersburg, Florida. Andrea turned northeastward and accelerated, reaching a peak intensity of 65 mph on the morning of June 6. Dry air caused the intensity to decrease to about 60 mph by 2200 UTC when Andrea made landfall about 10 miles south of Steinhatchee, Florida. The storm then moved quickly across northeastern Florida and southeastern Georgia and became extratropical as it merged with a front over South Carolina by 1800 UTC June 7. The cyclone moved rapidly along the U.S. east coast, eventually becoming absorbed by a low over Nova Scotia late on June 8. Andrea brought tropical storm conditions to portions of the coasts of Florida, Georgia, and South Carolina. The cyclone produced a maximum inundation of 2.6 ft at Cedar Key, Florida, and inundations of 1-2 ft were common elsewhere along the west coast of Florida, resulting in minor coastal flooding. Severe rainfall-induced flooding occurred over southeastern Broward and northeastern Miami-Dade counties well after the storm passed, with a maximum of 15.28 inches of rain at North Miami Beach. Andrea’s precursor low produced heavy rains over portions of western Cuba, with the maximum of 12.40 inches reported at La Capitana Mountain. Andrea is known to have caused ten tornadoes in Florida, one in North Carolina, and five in Cuba. Andrea is responsible for one direct death and minor property damage in the United States. 4.1.2 Tropical Storm Barry Barry formed from a tropical wave that moved into the southwestern Caribbean Sea by early on June 15. Deep convection flared up along the wave axis, and a broad low pressure area formed just north of Panama. The low moved across Nicaragua and Honduras and into the northwestern Caribbean Sea by early on June 17, and a tropical depression formed by 1200 UTC in the Gulf of Honduras. The depression made landfall near Big Creek, Belize about ten hours after genesis, turned to the northwest and then weakened over land. Barry became a tropical storm again on June 19 over the southern Bay of Campeche. The storm then turned westward and strengthened slightly before making landfall with 45 mph sustained winds at about 1115 UTC June 20 near Laguna La Mancha, Veracruz. The cyclone dissipated 12 hours later over high terrain. Barry or its precursor affected many countries in Latin America, triggering floods and mudslides in eastern Nicaragua and Honduras. Nearly 10 inches of rain fell across southern Belize, and at least 54 people had to be evacuated when their homes were flooded. Barry was responsible for five direct deaths. In El Salvador, one child was swept away by a flooded creek, and one person was killed and two were injured when they were struck by lightning. More than 26,000 people lost power across the Yucatan, and there were at least three direct fatalities in eastern Mexico. Significant damage occurred in Veracruz, where three more people were injured and 1,200 residents had to be evacuated. 4.1.3 Tropical Storm Chantal Chantal originated from a fast-moving tropical wave that travelled across the tropical Atlantic Ocean during the first week of July. A tropical storm formed on July 7 over the central tropical Atlantic, and the strengthening cyclone neared the Lesser Antilles early on July 9. Surface and aircraft data indicate that the storm reached a peak intensity of 65 mph while it moved just to the south of Martinique. Chantal raced across the eastern Caribbean Sea, and an increase in vertical shear caused the cyclone to weaken. The storm degenerated into a trough of low pressure while it moved south of Hispaniola late on July 10. Heavy rains and strong winds buffeted portions of the central Lesser Antilles during the morning of July 9. An elevated weather station at Trinité, Martinique, reported peak 1-minute winds of 69 mph with gusts to 75 mph. High winds reportedly ripped roofs off of houses in Dominica, and there was one direct death in the Dominican Republic when a firefighter was swept away by flood waters. Chantal is the fastest-moving tropical cyclone (with a 6-hour forward speed of 32 mph) observed in the deep Tropics (south of 20°N) in the Atlantic basin in the observational record during the satellite era (1966-present). 4.1.4 Tropical Storm Dorian Dorian developed from a tropical wave that spawned a tropical depression on July 23 a couple hundred miles south of the Cape Verde Islands. The cyclone intensified and reached its peak intensity of 60 mph on July 25, but a combination of dry air and moderate shear caused Dorian to weaken while it continued moving westward. Dorian degenerated into a trough on July 27 about 550 miles east of the northern Leeward Islands, and the remnants of the cyclone moved north of Puerto Rico and across the southeastern Bahamas during the next couple of days. The system turned northwestward on August 1 and northward the next day just east of Florida, where a closed area of low pressure formed. Dorian regenerated into a tropical depression around midday on August 2, when it was centered about 75 miles northwest of Freeport, Bahamas. The depression accelerated to the north and northeast, but an increase in shear caused it to again degenerate into a weak low a couple hundred miles southeast of South Carolina late on August 3. 4.1.5 Tropical Storm Erin The genesis of Erin was associated with a tropical wave and a broad surface low that departed the west coast of Africa on August 13. The circulation became better defined the next day, and a tropical depression formed on August 15 about 70 miles south of Praia in the Cape Verde Islands. Dry air prevented significant intensification while Erin moved west-northwestward and northwestward. The cyclone reached its peak intensity of 45 mph early on August 17, but very dry air and increasing shear caused Erin to degenerate into a remnant low on August 18 several hundred miles east of the northern Leeward Islands. 4.1.6 Tropical Storm Fernand Fernand formed from a complex interaction of two tropical waves, which led to a single westward-moving trough that reached the Yucatan Peninsula early on August 24. A broad low formed while the system moved westward across southeastern Mexico, and it became a tropical depression once it reached the Bay of Campeche early on August 25. Strengthening continued until Fernand made landfall with 60 mph winds at 0445 UTC August 26 near Zempoala, Mexico, and the storm dissipated over mountainous terrain just after 1800 UTC that day. A gust to 74 mph was measured at Veracruz Harbor at 0020 UTC August 26. Fernand generally produced storm total rainfall amounts of 5-9 inches over portions of the eastern slopes of the Sierra Madre Oriental Mountains. Reports indicate that 13 people died in landslides in Veracruz, and another man drowned in floodwaters in Oaxaca. One hundred houses were damaged in mudslides, and over 100,000 homes lost power during the storm. 4.1.7 Tropical Storm Gabrielle A tropical wave spawned an area of low pressure near the Lesser Antilles on August 31. The low moved very slowly toward the west-northwest for the next two days, and after the low was overtaken by a second tropical wave, a tropical depression formed late on September 4 about 120 miles south-southeast of Puerto Rico. The depression developed a large area of deep convection during the next several hours, but by the early morning of September 5, the low-level center had separated from a vigorous mid-level circulation. Later that day, the depression degenerated into a trough near the eastern tip of Hispaniola. The disturbance moved northward and then northeastward over the next four days. On September 9, a low-level center developed again near convection, leading to the reformation of a tropical depression on September 10 about 350 miles south of Bermuda. The cyclone continued moving to the north and reached its peak intensity of 65 mph twelve hours later. The storm passed about 20 miles west of Bermuda, and produced tropical storm-force winds over the island. Gabrielle then turned north-northeastward through a highly sheared environment, causing the surface center to dissipate on September 13. 4.1.8 Hurricane Humberto Humberto formed from a tropical wave, first developing as a tropical depression about 200 miles west-southwest of Dakar, Senegal on September 8. The cyclone gradually intensified while moving south of the Cape Verde Islands over the next couple of days, turning toward the northwest and north by September 11. Humberto quickly strengthened and became a hurricane early that morning, reaching its peak intensity of 90 mph. By September 13, however, the combination of increasing shear, cool waters, and a drier, more stable atmosphere led to gradual weakening. The cyclone turned toward the west-northwest, and the hostile environmental conditions caused Humberto to degenerate into a low around 0000 UTC September 14 about 800 miles northwest of Praia. The convection recovered sufficiently to again designate the system a tropical cyclone a day later, although strong vertical shear prevented any significant reintensification. The tropical storm then encountered a mid- to upper-level cyclone that caused the system to become a subtropical cyclone on September 17. Humberto gradually weakened and opened up into a trough on September 18, and its remnants were absorbed by an approaching cold front shortly thereafter. Heavy rains and gusty winds associated with Humberto affected the southern Cape Verde Islands, causing some minor flooding and downed trees. Humberto tied the record for the latest first hurricane formation of the year in the satellite era, previous set by Gustav in 2002. 4.1.9 Hurricane Ingrid A tropical wave moved into the western Caribbean Sea on September 7, where a large trough of low pressure extended from across Central America into the eastern Pacific. The combination of these systems led to formation of a low pressure area on September 11 just before the low moved over the Yucatan Peninsula. After the system moved over the Bay of Campeche, a tropical depression formed on September 12 about 175 miles east-northeast of Veracruz, Mexico. Ingrid made a small loop east of Veracruz on September 13 before turning generally northward. Despite moderate shear, the cyclone steadily intensified and reached a peak intensity of 85 mph early on September 15. The hurricane then turned northwestward and west-northwestward over the next 24 hours in response to a mid-level ridge over Texas ( Fig.2). Increasing shear caused the cyclone to weaken below hurricane strength, and the maximum winds had decreased to about 65 mph when the center made landfall just south of La Pesca, Mexico around 1115 UTC September 16. After landfall, Ingrid moved slowly westward and dissipated over northeastern Mexico on September 17. A combination of Ingrid, eastern Pacific Hurricane Manuel, and large-scale low-level southwesterly flow caused widespread heavy rains and mudslides over large portions of Mexico, with the heaviest rains associated with Ingrid occurring over the states of Tabasco, Veracruz, and Tamaulipas. Tuxpan reported a rainfall total of 20.11 inches during the period September 11-20. Twenty-three deaths are attributed to Ingrid, but some of these deaths may not have been directly related to the tropical cyclone. 4.1.10 Tropical Storm Jerry Jerry developed from a westward-moving tropical wave that showed increasing thunderstorm activity on September 27, leading to the formation of a tropical depression on September 29 about 850 miles east-northeast of the Leeward Islands. The cyclone turned northward and then north-northeastward later that day while it moved around the subtropical high. Jerry reached a peak intensity of 50 mph early on October 1 before gradually weakening due to increasing shear. The storm degenerated into a low late on October 3, when it was about 700 miles southwest of the central Azores. 4.1.11 Tropical Storm Karen Karen originated from a tropical wave interacting with an upper-level trough, which caused the formation of a surface trough southeast of Jamaica by September 28. The surface trough moved slowly westward during the next few days, and while the trough was accompanied by tropical-storm-force winds by October 2, the system lacked a low-level center. Surface observations suggest that a tropical storm finally formed early on 3 October about 40 miles north of Cancun, Mexico. The center of Karen then passed near the northeastern tip of the Yucatan peninsula and moved generally north-northwestward into the south-central Gulf of Mexico. Later that day, Karen reached its peak intensity of 65 mph, but strong shear and dry air aloft caused the storm to weaken. Westerly shear further increased, and Karen degenerated into an open trough a couple hundred miles south of the Louisiana coast on October 6. Karen is one of only a few named storms (e.g., Alberto 1982) during the reconnaissance era to have dissipated in the Gulf of Mexico without making landfall. 4.1.12 Tropical Storm Lorenzo Lorenzo originated from the northern portion of a tropical wave that departed the west coast of Africa on October 11. Vertical shear was too strong for development until a mid- to upper level trough cut off to the north of Puerto Rico on October 19, and a broad surface low formed the next day about 700 miles southeast of Bermuda. The surface low became better defined on October 21, marking the formation of a tropical depression about 550 miles east southeast of Bermuda. Later that day, the depression strengthened while the cyclone began moving north northeastward, and the system reached a peak intensity of 50 mph on October 22. The cyclone then moved slowly eastward before strong upper-level winds caused it to degenerate into a remnant low on October 24 well west of the Azores. 4.1.13 Tropical Storm Melissa Melissa developed from a non-tropical low that formed along a stationary front over the central Atlantic on November 17. Early the next day, the low acquired some tropical characteristics, becoming a subtropical storm about 650 miles east-southeast of Bermuda. Melissa moved north northwestward to northward over the next 24 hours, and the storm reached its first peak intensity of 65 mph early on November 19. Later that day, the thunderstorm activity diminished, and Melissa weakened while the cyclone turned northeastward. Thunderstorms developed over the circulation center early on November 20, helping the system develop a warm core and make the transition to a tropical cyclone. The tropical storm accelerated toward the east-northeast later that day, and matched its earlier peak intensity of 65 mph. Melissa lost its tropical characteristics on November 22 and degenerated into a trough about 400 miles west of Portugal early on November 23. 4.1.14 Unnamed Subtropical Storm A non-tropical area of low pressure formed on December 3 a few hundred miles south of the Azores. The low gradually acquired some tropical characteristics while making a small loop, and it became a subtropical storm early on December 5 with peak sustained winds of 50 mph. The storm then started moving generally to the north but conditions were not very favorable for strengthening, and the low gradually weakened. It was close to becoming a tropical storm on December 6, but the associated thunderstorm activity weakened before the transition could occur. The storm decayed into a non-convective low on December 7 just before it moved through the Azores. EASTERN NORTH PACIFIC Overall tropical cyclone activity during the 2013 eastern North Pacific hurricane season was below normal. Of the 18 tropical storms that formed, nine became hurricanes but only one reached major hurricane strength (category three or stronger on the Saffir-Simpson Hurricane Wind Scale) (Table 2, Figs.2a, 2b). In comparison, the 1981-2010 averages are 15 tropical storms, 8 hurricanes and 4 major hurricanes. Although the number of named storms was above average, many of these systems were weak and short-lived, causing the Accumulated Cyclone Energy (ACE) index to be only about 68% of the long-term median value. An unusually large number of cyclones affected coastal areas of Mexico. Hurricane Barbara crossed the southeastern coast of Mexico in late May, bringing Category 1 hurricane conditions. Heavy rains from Manuel inundated parts of southern Mexico in September, causing mud slides and a large loss of life. Tropical Storms Juliette, Octave, and Sonia also made landfall on either the Baja California peninsula or northwestern Mexico. Hurricane Erick and Tropical Storm Lorena also brushed portions of the Mexican coast, but with less significant impacts. 4.1.15 Tropical Storm Alvin A broad surface low associated with a tropical wave developed on May 13 in the far eastern Pacific basin, and a tropical depression formed from this low early on May 15 about 650 miles south-southwest of Acapulco, Mexico. Alvin turned west-northwestward, strengthening over warm waters. The cyclone reached its peak intensity of 60 mph early on May 16, but increasingly unfavorable environmental conditions resulted in the storm weakening almost as quickly as it had strengthened. By late on May 16, Alvin dissipated well offshore of southwestern Mexico. 4.1.16 Hurricane Barbara Barbara formed farther east than most tropical cyclones in the basin, becoming a tropical depression on May 28 about 125 miles south-southeast of Puerto Angel, Mexico. The cyclone turned northward and northeastward toward the coast of Mexico later that day, rapidly strengthening into a hurricane on May 29. Barbara made landfall near the border between the Mexican states of Oaxaca and Chiapas, about 20 miles west-southwest of Tonalá, with an intensity of about 80 mph (Fig 4). A wind gust of 75 mph was reported in Paredόn around the time of landfall. The hurricane quickly weakened while moving northward across the Sierra Madre Mountains and became a remnant low before reaching the Bay of Campeche, where it dissipated. Barbara was responsible for three direct deaths in Mexico, but damage was minimal. Barbara was the second-earliest hurricane landfall in the basin since records began in 1949. 4.1.17 Hurricane Cosme Cosme can be traced to the same tropical wave that spawned Tropical Storm Barry in the Gulf of Mexico. This wave led to the formation of a tropical depression about 500 miles south of Manzanillo, Mexico on June 23. Cosme moved northwestward on June 24, with the large storm steadily strengthening in an environment of low shear and warm waters. The system became a hurricane early on June 25 while turning west-northwestward and accelerating. The cyclone attained its peak intensity of 85 mph that same day before it reached much cooler waters. Rapid weakening occurred, and Cosme dissipated on June 27 about 690 miles west-southwest of Cabo San Lucas. 4.1.18 Hurricane Dalila A low pressure area generated by a tropical wave became a tropical depression on June 29 about 475 miles south of Manzanillo. The cyclone turned toward the north and northwest on June 30 and strengthened into a tropical storm while it moved parallel to the coast of Mexico, eventually becoming a hurricane on July 2 about 165 miles south-southwest of Cabo Corrientes, Mexico. Steering currents weakened, and Dalila was downgraded to a tropical storm late on July 3 while moving on an erratic west-southwestward course in a less conducive environment. Dalila degenerated into a remnant low pressure system on July 7 about 460 miles south-southwest of Cabo San Lucas, Mexico. 4.1.19 Hurricane Erick Erick originated from a tropical wave that moved into the eastern Pacific on June 29. A low pressure area developed along the wave and became better defined near the Gulf of Tehuantepec on July 2, leading to the formation of a tropical depression early on July 4 about 210 miles southeast of Acapulco. The cyclone moved west-northwestward, gradually strengthening and becoming a hurricane late on July 5. A few hours later the hurricane brushed the coast of southwestern Mexico. Erick weakened to a tropical storm around midday on July 7 when it moved over cooler waters. The decaying tropical storm moved near the southwestern coast of the Baja California peninsula on July 8 and 9 then dissipated. 4.1.20 Tropical Storm Flossie The genesis of Flossie appears to be partially associated with a tropical wave that reached the eastern Pacific basin on July 18. By July 24, the poorly organized disturbance was located well to the south-southwest of the Baja California peninsula. There was an increase in organization that day, and a tropical cyclone formed about a thousand miles west-southwest of the southern tip of the Baja California peninsula. Flossie gradually strengthened and reached a peak intensity of 70 mph early on July 27 when it was located just east of 140°W longitude. The tropical storm then weakened due to shear. A short period of re-intensification occurred early on July 28, but the weakening trend resumed later that day and then accelerated. Flossie weakened to a tropical depression late on July 29 near the northeastern portion of the Island of Maui and dissipated shortly after that. 4.1.21 Hurricane Gil A tropical wave spawned a broad low pressure area on July 29 over the central portion of the eastern Pacific basin, and a tropical depression formed the next day about 1025 miles south southwest of the southern tip of the Baja California peninsula. The cyclone was small in size and rapidly intensified into a hurricane 30 hours after genesis. Gil was initially steered west northwestward but turned westward on 1 August, reaching a peak intensity of 85 mph later that day. Unfavorable environmental conditions caused Gil to weaken to a tropical storm the following day, with the storm turning west-southwestward by August 3. Gil weakened to a tropical depression on August 4 and turned westward again, reacquiring tropical storm strength for a brief time on August 5 after crossing 140°W. The weakening trend resumed, and Gil degenerated into a remnant low late on August 6 well east-southeast of the Hawaiian Islands. The remnants of Gil moved west northwestward and dissipated two days later. 4.1.22 Hurricane Henriette The tropical wave trailing the disturbance that eventually became Hurricane Gil spawned a low pressure area on August 2 that developed into a tropical depression early the next day. The depression gained additional organization and became a tropical storm 12 hours later about 1180 miles southwest of the southern tip of the Baja California peninsula. Henriette moved slowly west southwestward and southwestward, but turned back toward the west and northwest on August 5 and 6. The cyclone gradually intensified, becoming a hurricane by late on August 5 and reaching an estimated intensity of 90 mph. Henriette unexpectedly strengthened a little more even though it was moving over cooler waters, and reached a peak intensity of 105 mph around early on August 8 while centered well east of Hilo, Hawaii. The hurricane crossed 140°W into the central Pacific basin on August 9 while weakening. Henriette became a depression by August 11 while it passed about 380 miles south of South Point on the Big Island of Hawaii, degenerated into a remnant low shortly thereafter, and then dissipated. 4.1.23 Tropical Storm Ivo A tropical wave moved into the eastern Pacific basin on August 15, with only slow development occurring in an environment of moderate to high shear. A tropical depression eventually formed early on August 22 about 500 miles west-southwest of Manzanillo. The depression then turned north-northwestward while a disturbance associated with the next tropical wave neared the depression. As the distance between the two systems gradually lessened, the center of the depression reformed in between the two systems early on August 23. The merged system strengthened into a tropical storm late on August 22 and moved northwestward, reaching a peak intensity of 45 mph before reaching considerably cooler waters. By late on August 24, Ivo turned back toward the north-northwest, and weakened to a tropical depression. The cyclone became a remnant low near the west-central coast of the Baja California peninsula later that day and dissipated soon after that. Heavy rains associated with the remnants of Ivo caused localized flooding in parts of the Baja California peninsula and in the southwestern United States on 24 and 25 August, with minor damage reported. 4.1.24 Tropical Storm Juliette Juliette developed from the same tropical wave that spawned Tropical Storm Fernand, after the wave interacted with the Intertropical Convergence Zone (ITCZ) south of the Gulf of Tehuantepec early on August 25. Three days later, a tropical storm formed about 115 miles west of Manzanillo. Even though the circulation of Juliette was quite small, the center passed close enough to produce sustained winds of 35 mph in Manzanillo. The small cyclone continued to strengthen during the day, and reached its peak intensity of 65 mph while located about 60 miles southeast of Punta Santa Marina on the Baja California peninsula early on August 29, where it made landfall a few hours later. The mountainous terrain of west-central Baja California peninsula severely disrupted the circulation of Juliette as it turned northwestward and slowed down, causing it to weaken to a remnant low late on August 30 just offshore. The system dissipated later that day. 4.1.25 Hurricane Kiko Kiko originated from the interaction between an eastern Pacific ITCZ disturbance and a tropical wave. The disturbance that resulted from the interaction of these two systems developed into a tropical depression about 530 miles southwest of the southern tip of the Baja California peninsula on August 30 and became a tropical storm on the next day. A period of rapid strengthening began when Kiko turned north-northeastward, and the cyclone became a hurricane with 75 mph winds early on September 1. Rapid weakening followed due to shear and cooler waters, and Kiko became a tropical storm later that day. Kiko degenerated into a remnant low about 400 miles west-southwest of the southern tip of the Baja California peninsula, where it dissipated on September 4. 4.1.26 Tropical Storm Lorena A tropical wave spawned a broad low pressure area south of the Gulf of Tehuantepec on September 2. The system moved slowly west-northwestward to northwestward, roughly parallel to the coast of southwestern Mexico, and a tropical depression formed about 145 miles southwest of Manzanillo, Mexico, the following day. Intensification was very gradual due to some southwesterly shear and a poorly organized structure. As Lorena approached Baja California Sur, the storm reached a peak intensity of 50 mph, but it weakened when it reached cooler waters. Lorena became a remnant low later that day about 60 miles west-southwest of Santa Fe, Mexico, and dissipated shortly after that. 4.1.27 Hurricane Manuel Manuel developed from the tropical wave that spawned Hurricane Ingrid in the Bay of Campeche. A concentrated area of thunderstorms associated with the wave produced a surface trough south of mainland Mexico on September 12, and the trough developed into a tropical depression the next day about 315 miles southeast of Manzanillo. The depression became a tropical storm later that day, initially moving slowly northwestward before turning north northeastward on September 14, partially in response to the proximity of Hurricane Ingrid located to the northeast. A gradual turn toward the northwest followed while Manuel steadily strengthened. The tropical storm reached an intensity of 70 mph before making landfall in the state of Michoacán, near Pichilinguillo, early on September 15. The cyclone then moved almost parallel to the coast for several hours, and passed near Manzanillo. Manuel quickly weakened after moving inland, but brought very heavy rains to a large portion of southwestern Mexico, resulting in deadly flash flooding and mud slides. Manuel degenerated into a weak low-level trough early on September 16. The remnants of Manuel emerged over the southern Gulf of California around midday on September 16, and a well-defined surface circulation redeveloped about 170 miles east of Cabo San Lucas, Mexico. Once again, Manuel became a tropical depression, moving slowly northwestward in an environment of low shear and very warm waters that was highly conducive for rapid intensification. Manuel reached its peak intensity of 75 mph late on September 18 before making landfall just west of Culiacán, Mexico, early on September 19( Fig.5). The second landfall of Manuel was associated with additional flash flooding and mud slides in Mexico. The hurricane quickly weakened after moving inland, and dissipated over the Sierra Madre Occidental mountains a few hours later. At least 102 direct deaths in Mexico are attributed to Manuel. Nearly all of these deaths were the result of heavy rains, especially in mountainous areas, as was the case in the state of Guerrero, where a mud slide destroyed nearly half of the village of La Pintada. Based on reports from the Global insurance and Catastrophic Modeling companies (AON Benfield and Eqecat, Inc.,) the estimates of total insured losses due to Manuel, including economic impacts, are around $4.2 billion (US), with the largest losses occurring in Guerrero. 4.1.28 Tropical Storm Narda Narda originated from a tropical wave that reached the eastern Pacific basin on September 27. The wave remained dormant for over a week until it spawned a low pressure area that developed into a tropical depression around midday on October 6 about 865 miles southwest of the southern tip of the Baja California peninsula. Moving westward to west-northwestward into favorable environmental conditions, the depression became a tropical storm late on October 6 and reached a peak intensity of 65 mph later that day. Weakening occurred after that time over cooler waters, and Narda became a tropical depression late on October 8, a remnant low early on October 10, and dissipated a couple of days later. 4.1.29 Tropical Storm Octave Octave formed from the merger of a tropical wave and a pre-existing disturbance over the eastern Pacific, resulting in a tropical depression about 545 miles south of the southern tip of the Baja California peninsula on October 12. Octave steadily strengthened and reached its peak intensity of 65 mph around midday on October 13. The storm turned northward but began to weaken on its approach to the Baja California peninsula, making landfall very early on October 15 just north of Cabo San Lazaro, with maximum winds of 45 mph. Octave weakened further and became a tropical depression later that morning. The cyclone degenerated into a remnant low that afternoon several hours before moving inland over mainland Mexico and dissipated. 4.1.30 Tropical Storm Priscilla Priscilla formed from an area of thunderstorms that formed along the ITCZ well south-southwest of the Baja California peninsula on October 7 and 8. Despite the proximity of Octave, the disturbance became a tropical depression late on October 13 about 810 miles south-southwest of the southern tip of the Baja California peninsula. The depression moved north-northeastward and northward, strengthened into a tropical storm a few hours after genesis, and reached an estimated peak intensity of 45 mph later on October 14. Priscilla then weakened over cooler waters when the cyclone turned west-northwestward on October 15. Late that day Priscilla weakened to a tropical depression. The cyclone degenerated into a remnant low several hours later and dissipated on October 16. 4.1.31 Hurricane Raymond An ITCZ disturbance moved into the eastern Pacific basin on October 16, and became better organized as it passed south of the Gulf of Tehuantepec on October 18. A low pressure center formed on October 19 and became a tropical depression later that day about 220 miles south-southwest of Acapulco, Mexico, and a tropical storm soon thereafter. Over water temperatures near 30°C and in low shear, Raymond moved northwestward and rapidly intensified from a 35-mph tropical depression to a 125-mph category 3 hurricane over a period of 42 hours, reaching its peak intensity about 90 miles south-southwest of Zihuatanejo, Mexico. In an environment of light steering winds, Raymond drifted erratically on October 21 and 22, making a small clockwise loop just off the Mexican coast. Weakening occurred when Raymond stalled on October 22, likely due to upwelled colder water beneath the cyclone. Raymond weakened almost as rapidly as it had strengthened, becoming a tropical storm by very late on October 23. The storm moved west-southwestward and westward away from the Mexican coast in response to a building ridge of high pressure through October 26. Vertical shear decreased on October 24, and the cyclone began a second period of rapid intensification on October 26, with Raymond reaching hurricane strength again early on October 27 about 725 miles south southwest of the southern tip of the Baja California peninsula and a secondary peak intensity of 105 mph later that day. The ridge to the north of Raymond weakened, and the cyclone turned abruptly northwestward and northward on October 28. Increasing shear caused Raymond to weaken back to a tropical storm by late that day. Raymond turned northeastward in response to an approaching trough on October 30, with the cyclone weakening to a tropical depression early that day and degenerating into a remnant low a few hours later about 370 miles west-southwest of the southern tip of the Baja California peninsula. The remnant low turned westward and dissipated on October 31. An Air Force Hurricane Hunter reconnaissance aircraft investigated Raymond when the hurricane was south of Mexico (Fig.6). 4.1.32 Tropical Storm Sonia A tropical depression formed from a tropical wave early on November 1 about 320 miles southwest of Manzanillo. The depression turned west-northwestward and moved slightly faster with little change in strength. A trough digging into the western United States caused the depression to turn northward early on November 3, with the system strengthening into a tropical storm late that day. Sonia turned northeastward and accelerated, reaching a peak intensity of 45 mph while passing just south of the southern tip of the Baja California peninsula. Sonia maintained tropical storm strength through landfall near El Dorado in the state of Sinaloa early on November 4 despite strong shear. The cyclone moved inland and quickly weakened to a tropical depression, dissipating within a few hours over the high terrain of northwestern Mexico. 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 2013 official forecast errors for the Atlantic and Eastern North Pacific are included in Figures 7 and 8, respectively. Table 1. Summary of activity of the 2013 Atlantic hurricane season.
a TD - tropical depression maximum 1-minute sustained winds 38 mph or less; TS - tropical storm, winds 39-73 mph; H - hurricane, winds 74-110 mph; SS – subtropical storm, winds 39 mph or greater.
Table. 2 . 2013 eastern North Pacific Tropical Storms and Hurricanes
a TS - tropical storm, maximum sustained winds 39-73 mph; H - hurricane, maximum sustained winds 74-110 mph; MH – major hurricane, maximum winds 111 mph or greater. b Dates begin at 0000 UTC and include tropical/subtropical depression stage, but exclude post-tropical stage. 
Figure 1. Tracks of Atlantic tropical storms and hurricanes during 2013. F Figure 3a . Tracks of the first nine eastern North Pacific tropical storms and hurricanes of 2013. 
Figure 3b. Tracks of the last nine tropical storms and hurricanes of 2013. 
Figure 4. Eye of Hurricane Barbara near the coast of Mexico. Eye of Hurricane Barbara observed on a microwave image (right). Microwave image is courtesy of the Naval Research Laboratory. 
Fig. 5. Hurricane Manuel making landfall over western Mexico observed by the Guasabe Radar. Image provided by CONAGUA.
Figure 6. Wind data from an Air Force Reconnaissance mission (AF300) to Hurricane Raymond located south of Mexico.
Figure7. Track and intensity forecast errors for the 2013 Atlantic hurricane season. 
Figure8. Track and intensity forecast errors for the 2013 eastern North Pacific hurricane season. Directory: pages -> prog -> www -> tcp -> documents documents -> Review of the ra IV hurricane operational plan documents -> Cyclone programme documents -> World meteorological organization technical document documents -> World meteorological organization ra IV hurricane committee thirty-fourth session documents -> World meteorological organization ra IV hurricane committee thirty-third session documents -> Review of the past hurricane season documents -> Ra IV hurricane committee thirty-fourth session ponte vedra beach, fl, usa documents -> World meteorological organization ra IV hurricane committee thirty-second session documents -> World meteorological organization ra IV hurricane committee thirty-fifth session documents -> English only review of the tropical cyclone operational plan for the south pacific and south-east indian ocean Download 160.05 Kb. Share with your friends:
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igure2. Satellite image and track guidance associated with Hurricane Ingrid when the cyclone was located in the Bay of Campeche, Mexico.
