|Category 4 major hurricane (SSHWS/NWS)|
|Formed||September 29, 2018|
|Dissipated||October 13, 2018|
|Highest winds|| 1-minute sustained:140 mph (220 km/h)|
|Lowest pressure||942 mbar (hPa); 27.82 inHg|
|Damage||$402.1 million (2018 USD)|
|Areas affected||Baja California Peninsula, Northwestern Mexico, Southwestern United States, Texas|
|Part of the 2018 Pacific hurricane season|
Hurricane Sergio was a powerful and long-lived tropical cyclone that affected the Baja California Peninsula as a tropical storm. Sergio became the eighth Category 4 hurricane in the East Pacific for 2018, breaking the old record of seven which was set in 2015. The twentieth named storm, eleventh hurricane, and ninth major hurricane of the season, Sergio originated from a broad area of low pressure that formed a few hundred miles south-southeast of the southern coast of Mexico on September 26. The National Hurricane Center monitored the disturbance for a few days until it organized into a tropical storm, after which it was assigned the name Sergio. The system gradually strengthened for the next couple of days, becoming a hurricane on October 2. Sergio then began a period of rapid intensification, becoming a major hurricane later that day. Intensification then halted for about twelve hours before resuming on October 3. The next day, Sergio peaked as a Category 4 hurricane with maximum sustained winds of 140 mph (220 km/h) and a minimum central pressure of 942 mbar (27.82 inHg). Sergio maintained peak intensity for six hours before beginning to weaken. On October 5, the system bottomed out as a low-end Category 3 hurricane. Sergio then began another period of intensification, achieving a secondary peak on October 6. The next day, Sergio began to weaken again, falling below major hurricane strength. At the same time, Sergio unexpectedly assumed the structure of an annular tropical cyclone. By October 9, Sergio had weakened into a tropical storm. On October 12, Sergio made landfall as a tropical storm on the Baja California Peninsula, and later in northwestern Mexico as a tropical depression before dissipating early on October 13.
A tropical cyclone is a rapidly rotating storm system characterized by a low-pressure center, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain. Depending on its location and strength, a tropical cyclone is referred to by different names, including hurricane, typhoon, tropical storm, cyclonic storm, tropical depression, and simply cyclone. A hurricane is a tropical cyclone that occurs in the Atlantic Ocean and northeastern Pacific Ocean, and a typhoon occurs in the northwestern Pacific Ocean; in the south Pacific or Indian Ocean, comparable storms are referred to simply as "tropical cyclones" or "severe cyclonic storms".
The Baja California Peninsula is a peninsula in Northwestern Mexico. It separates the Pacific Ocean from the Gulf of California. The peninsula extends 1,247 km from Mexicali, Baja California in the north to Cabo San Lucas, Baja California Sur in the south. It ranges from 40 km at its narrowest to 320 km at its widest point and has approximately 3,000 km of coastline and approximately 65 islands. The total area of the Baja California Peninsula is 143,390 km2 (55,360 sq mi).
The 2018 Pacific hurricane season produced the highest accumulated cyclone energy (ACE) value on record in the Eastern Pacific basin. With 23 named storms, it was the fourth-most active season on record, tied with 1982. The season officially began on May 15 in the eastern Pacific, and on June 1 in the central Pacific; they both ended on November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in the Pacific basin, as illustrated when the first tropical depression formed on May 10.
On October 10, Sergio's approach warranted the issuance of tropical storm watches and warnings along the western and eastern coasts of Baja California. Sergio made landfall in western Baja California Sur and Sonora on October 13 as a weak tropical storm, causing over US$2 million in damages, over a thousand school closures, and a few hundred evacuations due to severe flooding. The remnants of Sergio also brought heavy rainfall to Arizona, resulting in the closure of its state fair. Throughout Mexico and Arizona, no injuries or deaths were reported. Heavy rainfall also occurred in Texas, resulting in around US$400 million in damage and one death. Multiple tornadoes also spawned as a result of the increased moisture.
Sonora, officially Estado Libre y Soberano de Sonora, is one of 31 states that, with Mexico City, comprise the 32 federal entities of United Mexican States. It is divided into 72 municipalities; the capital city is Hermosillo. Sonora is bordered by the states of Chihuahua to the east, Baja California to the northwest and Sinaloa to the south. To the north, it shares the U.S.–Mexico border with the states of Arizona and New Mexico, and on the west has a significant share of the coastline of the Gulf of California.
The United States dollar is the official currency of the United States and its territories per the United States Constitution since 1792. In practice, the dollar is divided into 100 smaller cent (¢) units, but is occasionally divided into 1000 mills (₥) for accounting. The circulating paper money consists of Federal Reserve Notes that are denominated in United States dollars.
Arizona is a state in the southwestern region of the United States. It is also part of the Western and the Mountain states. It is the sixth largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona shares the Four Corners region with Utah, Colorado, and New Mexico; its other neighboring states are Nevada and California to the west and the Mexican states of Sonora and Baja California to the south and southwest.
The origins of Hurricane Sergio can be traced to a system that was located over northwestern South America on September 24.On September 25, the National Hurricane Center (NHC) forecasted that an area of low pressure would form a few hundred miles south or southwest of the Gulf of Tehuantepec in a couple days. On September 26 at 12:00 UTC, a broad area of low pressure formed a few hundred miles south-southeast of the southern coast of Mexico. The NHC continued to track the disturbance for a couple more days as it moved west-northwest. On September 29 at 12:00 UTC, Tropical Storm Sergio formed approximately 345 miles (555 km) south-southwest of Acapulco, Mexico. The NHC later discussed that Sergio was indeed a tropical storm, but without an inner wind core. Instead, the maximum sustained winds were located in a band approximately 125 mi (205 km) east of the center.
The National Hurricane Center (NHC) is the division of the United States' National Weather Service responsible for tracking and predicting tropical weather systems between the Prime Meridian and the 140th meridian west poleward to the 30th parallel north in the northeast Pacific Ocean and the 31st parallel north in the northern Atlantic Ocean. The agency, which is co-located with the Miami branch of the National Weather Service, is situated on the campus of Florida International University in University Park, Florida.
A low-pressure area, low, 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 partially counteracts the force of gravity.
Gulf of Tehuantepec is a large body of water on the Pacific coast of the Isthmus of Tehuantepec, southeastern Mexico, at. Many Pacific hurricanes form in or near this body of water. A strong, gale-force wind called the Tehuano periodically blows out over the waters of the Gulf of Tehuantepec, inducing strong upwelling of nutrient-rich waters which support abundant sea life.
Sergio continued to gradually intensify over the next couple of days, becoming a hurricane on October 2 at 00:00 UTC. −85 °C (−121 °F). Sergio then began a period of rapid intensification, becoming a major hurricane at 18:00 UTC. Soon after, the intensification halted as northwesterly shear affected Sergio's inner core, with microwave data indicating an open eyewall on the north side of the hurricane. Sergio maintained its intensity for 18 hours before resuming intensification. At the same time, the mid-level ridge to the north had weakened, resulting in Sergio travelling to the northwest. On October 4 at 00:00 UTC, Sergio became the eighth Category 4 hurricane of the season, breaking the old record of 7 which was set in 2015. Six hours later, Sergio peaked with maximum sustained winds of 140 mph (220 km/h) and a minimum central pressure of 942 mbar (27.82 inHg). Sergio maintained peak intensity for 12 hours before beginning to weaken. At 03:00 UTC on October 5, it was noted that Sergio's structure had deteriorated, with cloud tops warming and the eye becoming ragged and less distinct. At 09:00 UTC, Sergio began to turn due to a mid-level ridge that was developing to the northwest. Over the next couple of days, Sergio turned from the northwest to the southwest. At 06:00 UTC, Sergio bottomed out as a low-end Category 3 hurricane.At this time, Sergio had a well defined eye underneath a deep convective overcast with cloud tops around
The eye is a region of mostly calm weather at the center of strong tropical cyclones. The eye of a storm is a roughly circular area, typically 30–65 km (20–40 miles) in diameter. It is surrounded by the eyewall, a ring of towering thunderstorms where the most severe weather and highest winds occur. The cyclone's lowest barometric pressure occurs in the eye and can be as much as 15 percent lower than the pressure outside the storm.
The central dense overcast, or CDO, of a tropical cyclone or strong subtropical cyclone is the large central area of thunderstorms surrounding its circulation center, caused by the formation of its eyewall. It can be round, angular, oval, or irregular in shape. This feature shows up in tropical cyclones of tropical storm or hurricane strength. How far the center is embedded within the CDO, and the temperature difference between the cloud tops within the CDO and the cyclone's eye, can help determine a tropical cyclone's intensity. Locating the center within the CDO can be a problem for strong tropical storms and with systems of minimal hurricane strength as its location can be obscured by the CDO's high cloud canopy. This center location problem can be resolved through the use of microwave satellite imagery.
Rapid intensification is a meteorological condition that occurs when a tropical cyclone intensifies dramatically in a short period of time. The United States National Hurricane Center (NHC) defines rapid intensification as an increase in the maximum 1-min sustained winds of a tropical cyclone of at least 30 knots in a 24-hour period.
Late on October 5, Sergio began another period of intensification, reaching a secondary peak with winds of 125 mph (205 km/h) on October 6 at 00:00 UTC. Twelve hours later, a shortwave trough weakened the ridge to the northwest, resulting in the commencement of another turn. Over the next few days, Sergio turned from the southwest to the northeast. After maintaining secondary peak intensity for eighteen hours, Sergio began to weaken due to upwelling at 00:00 UTC on October 7. On October 7, after having weakened to a Category 2 hurricane, Sergio unexpectedly acquired the structure of an annular hurricane. At the same time, it was reported that the eye had doubled in size overnight. At 00:00 UTC the next day, Sergio weakened to a Category 1 hurricane. On October 9, at 18:00 UTC, Sergio weakened to a tropical storm, due to deteriorating conditions. Around 12:00 UTC on October 12, Sergio made landfall near Los Castros, Baja California Sur, as a tropical storm, with winds of 50 mph (85 km/h). Shortly after 18:00 UTC, Sergio made landfall near Guaymas, Sonora, as a tropical depression. At 00:00 UTC on October 13, Sergio dissipated over northwestern Mexico.
A trough is an elongated (extended) region of relatively low atmospheric pressure, often associated with fronts. Troughs may be at the surface, or aloft, or both under various conditions. Most troughs bring clouds, showers, and a wind shift, particularly following the passage of the trough. This results from convergence or "squeezing" which forces lifting of moist air behind the trough line.
An annular tropical cyclone is a tropical cyclone that features a normal to large, symmetric eye surrounded by a thick and uniform ring of intense convection, often having a relative lack of discrete rainbands, and bearing a symmetric appearance in general. As a result, the appearance of an annular tropical cyclone can be referred to as akin to a tire or doughnut. Annular characteristics can be attained as tropical cyclones intensify; however, outside the processes that drive the transition from asymmetric systems to annular systems and the abnormal resistance to negative environmental factors found in storms with annular features, annular tropical cyclones behave similarly to asymmetric storms. Most research related to annular tropical cyclones is limited to satellite imagery and aircraft reconnaissance as the conditions thought to give rise to annular characteristics normally occur over water well removed from landmasses where surface observations are possible.
Baja California Sur, officially the Estado Libre y Soberano de Baja California Sur, is the second-smallest Mexican state by population and the 31st admitted state of the 31 states which, with Mexico City, make up the 32 Federal Entities of Mexico.
On October 10, the Government of Mexico issued a Tropical Storm Watch along the western coast of the Baja California Peninsula from Punta Eugenia to Cabo San Lazaro and along the eastern coast from Bahia San Juan Bautistato San Evaristo. Early on the next day, as Sergio rapidly approached the peninsula, tropical storm watch on the west coast was upgraded to a tropical storm warning. The watches on the east coast were also upgraded to Tropical Storm Warnings later on the same day. All watches and warnings were discontinued as Sergio moved inland.
Punta Eugenia is a headland in the Mulegé Municipality, and is the westernmost point on the mainland of the state of Baja California Sur. To its north west lie Isla Natividad, Cedros Island and the Islas San Benito.
Sergio made landfall in western Baja California Sur and Sonora, bringing heavy rains and strong winds to northern Mexico. In Baja California Sur, multiple roads and schools located in Loreto were damaged. In Sonora, almost 400 people had to evacuate to a temporary shelter due to the threat of flooding. Strong winds up to 43 mph (70 km/h) downed trees and utility poles in Guaymas. Damage in the city was estimated at approximately MX$40 million (US$2.12 million), with houses and businesses suffering damages. In Punta de Aqua II, over 5.05 inches (128 mm) of rain was reported. Additionally, Mazatlán and Plutarco Elías Calles reported rainfall totals of 4.59 inches (117 mm) and 4.53 inches (115 mm), respectively. More than 1,000 schools were closed in Chihuahua and classes in eight municipalities of Sinaloa were suspended. However, there were no deaths or injuries reported.
Sergio's remnants bought powerful thunderstorms to Southern California on the evening of October 12. Rain extended into October 13, with scattered showers in the morning, followed by cloudiness in the afternoon and night. One of the thunderstorms triggered by the remnants of Sergio caused a blackout that left thousands in the dark.
The remnants of Sergio also moved into Arizona and Texas, bringing heavy rains and spawning multiple tornadoes. 3 inches (76 mm), and water ankle deep. The Arizona State Fair was closed due to flooding, the first time in "recent memory". In Texas, heavy rainfall in Llano County caused severe flooding. A rainfall total of 9.27 inches (235 mm) was reported at Castell. Additionally, Llano saw 6.26 inches (159 mm) of rain. The water level of Llano River rose about 25 feet (7.6 m) in 12 hours, causing a bridge in Kingsland to collapse. The cost to replace the bridge was estimated at US$20 million. In Llano, a 58-year-old woman drowned in her vehicle. Additionally, telephone and internet service went down after wires underneath the Llano River Bridge were swept away by floodwaters. Throughout the county, 38 homes were destroyed and over 600 sustained damages from flooding. Flood damages were estimated at US$50 million. Near Lake Travis in Travis County, 176 homes sustained damages from floods and over 200 more were affected. In Kerr County, a rainfall total of 8.40 inches (213 mm) was recorded at Mountain Home. At Lake Lyndon B. Johnson and Lake Marble Falls in Burnet County, 17 homes were destroyed, 232 were damaged, and 31 were affected. Damages to houses at both lakes are estimated at US$30 million total. In total, one person was killed and the economic loss of the flooding was about US$400 million. Multiple tornadoes spawned as a result of the increased moisture. An EF0 tornado uprooted a tree and caused roof damage in Brady. Doppler radar detected another tornado near Hillsboro and Bynum. Multiple tornadoes were sighted on Interstate 45 near Angus in Navarro County and north-northwest of Buffalo in Freestone County. Another tornado downed trees and caused power flashes near Henderson.In Arizona, some areas in Phoenix recorded rainfall totals of
The 1995 Atlantic hurricane season was a hyperactive Atlantic hurricane season that is generally considered to be the start of an ongoing era of high-activity tropical cyclone formation in the Atlantic basin. It is tied with 1887, 2010, 2011, and 2012 for having the third most number of named storms. The season produced twenty-one tropical cyclones, nineteen named storms, as well as eleven hurricanes and five major hurricanes. The season officially began on June 1 and ended on November 30, dates which conventionally delimit the period of each year when most tropical cyclones develop in the Atlantic basin. The first tropical cyclone, Hurricane Allison, developed on June 2, while the season's final storm, Hurricane Tanya, transitioned into an extratropical cyclone on November 1.
The 2000 Atlantic hurricane season was the first Atlantic hurricane season without a tropical cyclone in the month of July since 1993. The hurricane season officially began on June 1, and ended on November 30. It was slightly above average due to a La Niña weather pattern although most of the storms were weak. The first cyclone, Tropical Depression One, developed in the southern Gulf of Mexico on June 7 and dissipated after an uneventful duration. However, it would be almost two months before the first named storm, Alberto, formed near Cape Verde; Alberto also dissipated with no effects on land. Several other tropical cyclones—Tropical Depression Two, Tropical Depression Four, Chris, Ernesto, Nadine, and an unnamed subtropical storm—did not impact land. Five additional storms—Tropical Depression Nine, Florence, Isaac, Joyce, and Leslie—minimally affected land areas.
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Hurricane Lidia was the strongest tropical cyclone of the 1993 Pacific hurricane season. Forming from a tropical wave on September 8, Lidia steadily organized and became a hurricane on September 10. The hurricane continued to strengthen while developing a well-defined eye, and peaked as a Category 4 hurricane on September 11. However, it weakened considerably before making landfall in Sinaloa as a Category 2 storm. Lidia dissipated near Austin on September 14 and was later absorbed by a cold front. Across Mexico, the hurricane killed seven people; over 100,000 people were forced to evacuate their homes. A total of 160 homes were destroyed and 10,000 people were left homeless because of the storm. In the United States, five people suffered injuries and storm damage totaled $8 million.
Hurricane Rina was a powerful but slow-moving tropical cyclone that caused minor impacts in the northwestern Caribbean Sea in late October 2011. The seventeenth named storm, seventh hurricane, and fourth major hurricane of the annual hurricane season, Rina developed from a tropical wave in the western Caribbean on October 23. The depression quickly intensified, and was upgraded to Tropical Storm Rina early on the following day. Further strengthening ensued as it tracked west-northwestward, with Rina becoming a hurricane on October 24. The hurricane eventually peaked as a Category 3 hurricane while it moved generally westward on October 25. However, on October 26, Rina weakened substantially and was downgraded to a Category 1 hurricane. Further weakening occurred, with Rina falling to tropical storm intensity on October 27. Rina then made landfall in northern Quintana Roo early the next day. The cyclone degenerated into a remnant low later on October 28 after emerging into the Yucatán Channel. The low dissipated near the western tip of Cuba on October 29.
Hurricane Raymond was the only major hurricane in the eastern Pacific in 2013 and briefly threatened the southwestern coast of Mexico before recurving back out to sea. The seventeenth named storm and eighth hurricane of the annual cyclone season, Raymond developed from a tropical wave on October 20 south of Acapulco, Mexico. Within favorable conditions for tropical cyclone development, Raymond quickly intensified, attaining tropical storm intensity and later hurricane intensity within a day of cyclogenesis. On October 21, the hurricane reached its peak intensity with winds of 125 mph (205 km/h). A blocking ridge forced the hurricane to the southwest, while at the same time Raymond began to quickly weaken due to wind shear. The following day, the tropical cyclone weakened to tropical storm status. After tracking westward, Raymond reentered more favorable conditions, allowing it to intensify back to hurricane strength on October 27 while curving northward. The hurricane reached a secondary peak intensity with winds of 105 mph (165 km/h) several hours later. Deteriorating atmospheric conditions resulted in Raymond weakening for a final time, and on October 30, the National Hurricane Center (NHC) declared the tropical cyclone to have dissipated.
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Hurricane Odile is tied for the most intense landfalling tropical cyclone on the Baja California Peninsula during the satellite era. Sweeping across the peninsula in September 2014, Odile inflicted widespread damage, particularly in the state of Baja California Sur, in addition to causing lesser impacts on the Mexican mainland and Southwestern United States. The precursor to Odile developed into a tropical depression south of Mexico on September 10 and quickly reached tropical storm strength. After meandering for several days, Odile began to track northwestward, intensifying to hurricane status before rapidly reaching its Category 4 hurricane peak intensity on September 14. The cyclone slightly weakened before making landfall near Cabo San Lucas with winds of 125 mph (205 km/h). Odile gradually weakened as it tracked across the length of the Baja California Peninsula, briefly crossing into the Gulf of California before degenerating into a remnant system on September 17. These remnants tracked northeastward across the Southwestern United States before they were no longer identifiable on September 19.
Hurricane Bud was a powerful tropical cyclone that produced heavy rainfall and flash flooding across Northwestern Mexico and the Southwestern United States. The second named storm and major hurricane of the 2018 Pacific hurricane season, Bud originated from a tropical wave that departed from Africa on May 29. It then travelled across the Atlantic Ocean before crossing over South America and entering the Northeast Pacific Ocean late on June 6. The system then moved northwest and steadily organized, becoming a tropical depression late on June 9 and Tropical Storm Bud early the next day. Favorable upper-level winds and ample moisture allowed the storm to rapidly intensify to a hurricane late on June 10 and further to a major hurricane on June 11. Bud ultimately peaked the next morning with maximum sustained winds of 140 mph (220 km/h) and a minimum barometric pressure of 943 mbar. It curved north while rapidly succumbing to the effects of ocean upwelling, making landfall on Baja California Sur as a minimal tropical storm early on June 15. On the next day, land interaction and increasing wind shear caused Bud to degenerate to a remnant low, and Bud dissipated completely on June 16.
Tropical Storm Carlotta was a tropical cyclone that caused flooding in southwestern Mexico. Carlotta formed as the result of a breakdown in the Intertropical Convergence Zone to the south of Mexico. On June 12, the National Hurricane Center (NHC) reported that a broad area of low pressure had formed several hundred miles south of southeastern Mexico. The NHC continued to track the disturbance over the next couple of days as it drifted northward. After having increased in organization, the system was designated as a tropical depression on June 14. Late on the next day, the system strengthened into a tropical storm, after which it was named Carlotta. On June 16, Carlotta slowed down and unexpectedly stalled within a favorable environment, which led to more intensification than originally anticipated. Early on June 17, Carlotta reached peak intensity with maximum sustained winds of 65 mph and a minimum central pressure of 997 mbar. Soon after, Carlotta began to interact with land and experience wind shear, which resulted in the system weakening to tropical depression status later in the day. Carlotta weakened to a remnant low early on June 19 and dissipated several hours later.
Hurricane Olivia was the first tropical cyclone to make landfall on Maui and Lanai in recorded history. The fifteenth named storm, ninth hurricane, and sixth major hurricane of the 2018 Pacific hurricane season, Olivia formed southwest of Mexico on September 1. The depression slowly organized and strengthened into Tropical Storm Olivia on the next day. Olivia then began a period of rapid intensification on September 3, reaching its initial peak on September 5. Soon after, Olivia began a weakening trend, before re-intensifying on September 6. On the next day, Olivia peaked as a Category 4 hurricane, with winds of 130 mph and a minimum central pressure of 951 mbar. Six hours later, Olivia began another weakening trend that resulted in the hurricane being downgraded to Category 1 status on September 8, east of the 140th meridian west. On September 9, Olivia entered the Central Pacific Basin. Over the next couple of days, Olivia prompted the issuance of Tropical Storm Watches and Warnings for Hawaii County, Oahu, Maui County, and Kauai County. Olivia weakened into a tropical storm on September 11, before making brief landfalls in northwest Maui and Lanai on the next day, becoming the first tropical cyclone to impact the islands in recorded history. Tropical storm-force winds mainly affected Maui County and Oahu. Torrential rains affected the same area from September 11 to 13, causing flash flooding. Olivia caused a total of US$25 million in damages. Olivia was downgraded to a tropical depression on September 13 while continuing to head west. Due to wind shear disrupting Olivia's convection, the system weakened into a remnant low on September 14. Olivia crossed into the West Pacific Basin on September 19 as a remnant low, before dissipating later that day.
Hurricane Rosa was the first tropical cyclone to make landfall in the Mexican state of Baja California since Nora in 1997. The seventeenth named storm, tenth hurricane, and seventh major hurricane of the 2018 Pacific hurricane season, Rosa originated from a broad area of low pressure that the National Hurricane Center began monitoring on September 22. The disturbance moved westward and then west-northwestward for a few days, before developing into a tropical depression on September 25. Later that day, the depression strengthened into Tropical Storm Rosa. One day later, Rosa became a hurricane. On September 27, Rosa began a period of rapid intensification, ultimately peaking as a Category 4 hurricane with maximum sustained winds of 150 mph and a minimum central pressure of 936 mbar on the next day. Over the next couple of days, Rosa turned towards the northeast. By September 29, Rosa had weakened into a Category 2 hurricane due to ongoing structural changes and less favorable conditions. Later on the same day, Rosa re-intensified slightly. On September 30, Rosa resumed weakening as its core structure eroded. Early on October 1, Rosa weakened into a tropical storm. On October 2, Rosa weakened to a tropical depression and made landfall in Baja California. Later in the day, Rosa's remnants crossed into the Gulf of California, with its surface and mid-level remnants later separating entirely. The mid-level remnants of Rosa continued to travel north, reaching northeast Arizona late in the day. On October 3, Rosa's remnants were absorbed into an upper-level low situated off the coast of California.
Hurricane Leslie was the strongest cyclone of tropical origin to strike the Iberian Peninsula since 1842. A large, long-lived, and erratic tropical cyclone, Leslie was the twelfth named storm and sixth hurricane of the 2018 Atlantic hurricane season. The storm was of non-tropical origin, developing from a large low-pressure system that developed over the northern Atlantic Ocean on 22 September. The low quickly acquired subtropical characteristics and was classified as Subtropical Storm Leslie on the following day. The cyclone meandered over the northern Atlantic and gradually weakened, before merging with a frontal system on 25 September, which later intensified into a powerful hurricane-force low over the North Atlantic.
Tropical Storm Vicente was an unusually small tropical cyclone that made landfall as a tropical depression in the Mexican state of Michoacán on October 23, 2018, causing deadly mudslides. The twenty-first named storm of the 2018 Pacific hurricane season, Vicente originated from a trough of low pressure that formed within a large area of disturbed weather near Central America early on October 19. Around midday, the disturbance organized into a tropical depression, which prompted the National Hurricane Center to begin issuing advisories. Later in day, the depression strengthened into a tropical storm and was assigned the name Vicente. Despite having only been a weak tropical storm, Vicente developed an intermittent eye-like feature. Unfavorable conditions prevented strengthening until late on October 20. At that time, Vicente peaked with maximum sustained winds of 50 mph and a minimum central pressure of 1002 mbar. A day later, Vicente began to weaken due increasing wind shear before slightly restrengthening early on October 22. On October 23, Vicente weakened into a tropical depression. Later in the day, Vicente degenerated into a remnant low after making landfall in southwestern Mexico, before dissipating soon afterward.
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