1970 Pacific hurricane season

none EPac 1970 1970 Pacific hurricane season summary map.png May 30, 1970 November 8, 1970 Lorraine 963 85 1 21 19 5 0 0 direct, 22 indirect 1968, 1969, 1970, 1971, 1972 1970 Atlantic hurricane season 1970 Pacific typhoon season 1970 North Indian Ocean cyclone season The 1970 Pacific hurricane season was an active Northern Hemisphere hurricane season, especially during its early months. It officially started on May 15, 1970, in the eastern Pacific Ocean (east of 140°W), and on June 1, 1970, in the central Pacific (between 140°W and the International Date Line). It ended on November 30, 1970, in both regions. These dates conventionally delimit the period of each year when most tropical cyclogenesis occurs in these parts of the Pacific. This season had an above average number of storms. There were 21 tropical cyclones, of which 18 reached tropical storm strength. Four storms became hurricanes, of which none reached major hurricane strength. In the central Pacific, one hurricane and one tropical depression formed. One of the depressions crossed the Date Line to become a typhoon in the western Pacific. __TOC__ Systems Hurricane Adele EPac AdeleJun119702106z.jpg Adele 1970 track.png May 30 June 7 75 ≤ 992 An area of low pressure lacked strong convection until May 30, when it strengthened into Tropical Depression One-E. On May 31, the system further intensified into Tropical Storm Adele, the first named storm of the season. As Adele tracked westward, it strengthened into a hurricane on June 1 and reached its peak intensity soon afterward. As Adele moved west, a hostile environment caused it to weaken into a tropical storm. Adele further weakened, and it was downgraded into a depression on June 7. It degenerated into an open trough later that day. Tropical Storm Blanca EPac BlancaJun1019702213z.jpg Blanca 1970 track.png June 10 June 12 50 1002 The tropical disturbance that became Blanca was first noted on June 8 from satellite pictures. The new disturbance would reach tropical storm strength 24 hours later. Blanca moved in a northwest direction throughout its short life, dissipating on June 12. Tropical Storm Connie EPac ConnieJun1719702222z.jpg Connie 1970 track.png June 17 June 21 45 1001 Near the same location where Hurricane Adele formed two weeks earlier, a disturbance was noted on June 13. The disturbance abruptly became a tropical storm on June 17. The newly named Connie moved slowly to the northwest, reaching a peak intensity of 50 mi/h km/h on on June 18. Connie started weakening on June 19, finally dissipating on June 21 after stalling 118 mi km on from Clarion Island. Tropical Depression Dolores EPac Tropical Depression Dolores 1970.JPG Dolores 1970 track.png June 19 June 20 25 A disturbance first noted on June 19 had efficient outflow to be called a tropical depression. Satellite photos taken the same day revealed cloud structure that resembled a tropical storm forming, resulting in the system being called Dolores. The day after, no traces of a storm or of "Dolores" were found by reconnaissance. Post season analysis revealed Dolores to have only been a tropical depression. Tropical Storm Eileen EPac EileenJun281970.jpg Eileen 1970 track.png June 26 June 30 40 1005 A tropical depression formed just off the southern coast of Mexico on June 26. It headed northwestward, reaching storm strength on June 28. The next day, Eileen turned to the northeast, reached a peak of 45 mi/h km/h on winds, and hit western Mexico. Hurricane Francesca EPac FrancescaJuly61970ITOS1.gif Francesca 1970 track.png July 1 July 10 85 ≤ 991 Francesca was a Category 2 hurricane which was, for a period of time, obscured by a cap of clouds above the hurricane's eye, distorting the appearance of the hurricane. The precursor disturbance to Hurricane Francesca was first noticed on July 1. The system became a tropical depression later that day and reached tropical storm strength the next day. On July 3, data from a ship indicated winds of near 100 mi/h km/h on, which indicate a storm of Category 2 strength, near the center of Francesca. The cloud cap, which remained over the hurricane since it first became a hurricane, started to move off the lower clouds around the center of the system around July 5. A center fix was obtained, but the maximum sustained winds were unobtainable from the sea surface because of cloud cover in and around the center. Francesca started weakening on July 6, a fact made clear by reconnaissance which indicated that the system had weakened to a tropical storm. The further weakening was obscured by the cloud cover. The final reconnaissance on the weakening system was reported on July 8, two days before Francesca dissipated. Tropical Storm Gretchen EPac GretchenJuly1719702151z.gif Gretchen 1970 track.png July 14 July 21 45 1000 Gretchen was first noticed on satellite imagery on July 14. From then on out, Gretchen was a hard storm to predict, leading to large errors in forecasting. The storm dissipated on July 21. Tropical Storm Helga EPac HelgaJuly1719702151z.gif Helga 1970 track.png July 16 July 20 50 1007 The system that became Helga was first noticed on July 16. The next day, reconnaissance found a minimal tropical storm with winds of only 40 mi/h km/h on. Based on satellite imagery, Helga was believed to be gaining strength as it approached Baja California. At one point during intensification, the storm abruptly started weakening, and on July 19, after stalling less than 118 miles (190 km) south of the tip of Baja California, Helga dissipated. Tropical Storm Ione 1 EPac Ione2Jul2519702141ITOS1.gif Ione 2 1970 track.png July 22 July 26 45 A tropical depression developed off the southern coast of Mexico on July 22. A larger intensifying tropical cyclone was spotted by satellite at 2235 on the 24th near 17°N., 111°W. When the expanding circulation of this storm center reached the area of Ione, winds in the latter area decreased and it disappeared abruptly. The second storm, which was also named Ione, moved north-northwestward and began to weaken. Ione reached maximum sustained winds of 45 knots on the 25th near 20. N.,112°W. These winds decreased to 25 knots the next day as storm activity faded rapidly near 16 N., 113°W'. What was unusual about the system was that another tropical storm developed just to its northeast on July 24. That storm, also named Ione, tracked northward, reaching a peak of 60 mi/h km/h on winds before dissipating on July 25. Operationally, these were considered to be the same storm. Tropical Storm Ione 2 EPac Ione1Jul2519702141ITOS1.gif Ione 1 1970 track.png July 24 July 25 50 1007 A tropical depression was discovered near 14°N.,102°W., at 1800 on July 22, but it became disorganized as seen on satellite pictures the next day. Later events indicate it was splitting into two tropical cyclones, both of which were to attain tropical storm strength. The tropical storm first called lone was encountered by the KANIKAWA MARU at 2100 on July 24. That ship was buffeted by 48-kn southeasterly winds and 15-ft seas near 21°N, 107°W. The storm washed out the next day.Climatological Data National Summary 1970 Tropical Storm Joyce EPac Tropical Storm Joyce 1970.JPG Joyce 1970 track.png July 29 August 4 50 1000 A broad, flat low-pressure area persisted south of Baja California after Ione dissipated. On July 29, a small low circulation developed with a center about 120 nautical miles (220 km) south of Manzanillo. The system was given the name Joyce after winds of 40 mi/h km/h on were reported by a ship. In a similar way to Hurricane Francesca, Tropical Storm Joyce's low level center was unclear due to a cap of cirrus clouds. Joyce reached its peak intensity on July 31 with winds of near 60 mi/h km/h on before weakening, becoming a depression on August 1. Joyce dissipated on August 4. Tropical Storm Kristen EPac Sat19700807itos1Kristen.png Kristen 1970 track.png August 5 August 8 45 1005 Kristen was a loosely organized storm that formed from a disturbance that was causing squalls near the Mexican coast. Tropical storm-force winds were found on August 5. Kristen was tracked by ship reports and satellite pictures. Kristen reached its peak intensity of 50 mi/h km/h on winds on August 6. The storm dissipated on August 8 while over cold water. Hurricane Lorraine EPac LorraineAug2219702300UTCITOS1.gif Lorraine 1970 track.png August 16 August 27 85 963 Tropical Storm Lorraine, which formed on August 16 south of Mexico, intensified to a hurricane on the 20th. Two days later over open waters, it reached a peak of 95 mph (153 km/h) winds, but estimates from the Central Pacific Hurricane Center estimated it had winds of 115 mph (185 km/h). Without a chance to strengthen further, Lorraine weakened, finally dissipating on August 27 due to dry air. Tropical Storm Maggie EPac Tropical Storm Maggie.JPG Maggie 1970 track.png August 20 August 27 50 993 A flat low-pressure system appeared in an area of showers to the west-southwest of hurricane Lorraine around 1800 on the 20th. The French refrigerated cargo carrier BIAFRA was buffeted by 38-kn southerly winds, with a barometer reading 1006 mbar, near 13'N, 132'W, by the soon to be named tropical storm Maggie at 0000 on the 21st. Maggie intensified slowly while moving west-northwestward at 9 kn; her maximum winds were estimated at 55 kn at 0300 on the 25th. Maggie passed about 80 mi south of the island of Hawaii on the 25th, dumping torrential rains over the big island. Rainfall amounts ranged from 10 to 15 in on the windward side of the island from the Hamuka coast to Puna and from 1 to 7 in on the leeward side. Maggie was downgraded to a tropical depression at 0900 on the 26th near 18N, 157W. A westward turn saved Hawaii from a direct hit, but Maggie still brought strong surf and heavy yet beneficial rain to the island of Hawaii. There is some evidence that the remains of Maggie redeveloped into Hurricane Dot in the Central Pacific on September 1. Tropical Storm Norma EPAC Tropical Storm Norma (1970).JPG Norma 1970 track.png August 31 September 6 50 988 Tropical Storm Norma (1970) Norma was an indirect but essential cause of a flood disaster in Arizona that became known as the "Labor Day Storm of 1970". A depression formed August 31 and rapidly intensified into a tropical storm. Moving rapidly, it headed out to sea before slowing down and weakening. Norma's circulation fed humid unstable air into a large extratropical cyclone over Arizona. As Norma dissipated, record rains fell over the state from September 4 to September 6. The rains were deadly. There were a total of 22 deaths, including 14 from a flash flood on a creek. The damage amounted to over 1 million dollars. Hurricane Dot EPac Dot 1970-09-02.jpg Dot 1970 track.png September 1 September 4 70 993 A tropical disturbance, possibly the remnants of Tropical Storm Maggie, became a tropical depression on September 1 to the northwest of Hawaii. It moved to the northwest, coming within miles of the International Date Line and Midway Island but remaining in the Central Pacific. Dot turned to the northeast, reaching tropical storm strength on September 2 and hurricane strength September 3 before being absorbed by a cold core system the next day. When Dot became a hurricane at 35° north, it became the highest latitude for a storm to reach hurricane strength east of the International Dateline. This record was soon eclipsed by Hurricane 12 of the 1975 season. A flight flown into Dot also flew into Typhoon Clara. Tropical Storm Orlene EPac Orlene 1970-09-08 1725Z.jpg Orlene 1970 track.png September 7 September 9 55 995 65 mi/h km/h on Tropical Storm Orlene hit Mexico in eastern Oaxaca on September 8, having maintained a northeast track for its short lifetime. Hurricane Patricia EPac Patriciaoct819702304UTCITOS1.gif Patricia 1970 track.png October 4 October 11 85 972 Hurricane Patricia was a strong Category 2 hurricane with winds of 95 mph, Patricia formed on October 4 and dissipated on October 11. Tropical Storm Rosalie EPac RosalieOct2219702249UTCITOS1.gif Rosalie 1970 track.png October 21 October 23 48 1006 Rosalie's existence was confirmed on October 21 by observation from a ship. Reconnaissance on the 22nd reported a central pressure of 1006 mb. After a slight regeneration on the 23rd, Rosalie began rapid dissipation, finally dissipating on the 23rd. Tropical Storm Selma EPac SelmaNov319702234ITOS1.gif Selma 1970 track.png November 1 November 8 60 995 The final storm of the season, Tropical Storm Selma, developed on November 1 to the southwest of Mexico. It meandered to the north, turning to the northeast and northwest before heading southeastward and dissipating on November 8. Storm names The following list of names was used for named storms that formed in the North Pacific Ocean east of 140°W in 1970.https://www.aoml.noaa.gov/general/lib/lib1/nhclib/Publications/NatHurricaneOpsPlans/HOPs-1970.pdf 95, 97 NOAA Office of the Federal Coordinator for Meteorological Services and Supporting Research Washington, D.C. National Hurricane Operations Plan May 1970 February 27, 2024 It was the same list used in the 1966 season, with the exception of Kristen, which replaced Kirsten.http://australiasevereweather.com/cyclones/2008/summ0711a.htm Monthly Global Tropical Cyclone Summary: November 2007 First Installment Gary Padgett July 11, 2008 Australian Severe Weather February 27, 2024 Storms were named Kristen, Norma, Orlene, Patricia, Rosalie, and Selma for the first time this season.February 27, 2024 Eastern North Pacific Tropical Cyclone Name History Atlantic Tropical Weather Center http://www.atwc.org/pachist.txt https://web.archive.org/web/20070929105925/http://www.atwc.org/pachist.txt September 29, 2007 dead The name Kristen was later respelled as Kirsten for 1974. Adele Blanca Connie Dolores Eileen Francesca Gretchen Helga Ione Joyce Kristen Lorraine* Maggie* Norma Orlene Patricia Rosalie Selma Toni Vivian Winona One named storm, listed below, formed in the North Pacific between 140°W and the International Date Line in 1970. At the time, storm names within this region were assigned by the Joint Typhoon Warning Center on Guam. Named storms in the table above that crossed into the area during the season are noted (*).Pao-Shin Chu Peng Wu University of Hawaii-Manoa 2008 February 27, 2024 Climatic Atlas of Tropical Cyclone Tracks over the Central North Pacific http://files.hawaii.gov/dbedt/op/czm/initiative/hazard/climatic_atlas_of_tropical_cyclone.pdf October 23, 2014 https://web.archive.org/web/20141023054832/http://files.hawaii.gov/dbedt/op/czm/initiative/hazard/climatic_atlas_of_tropical_cyclone.pdf live Dot Retirement List of retired Pacific hurricane names The name Adele was later retired without explanation.https://www.nhc.noaa.gov/aboutnames_history.shtml Tropical Cyclone Naming History and Retired Names National Hurricane Center Miami, Florida February 27, 2024 It was replaced with Aletta for the 1974 season. Administrative changes This is the first season that the Redwood City-based Eastern Pacific Hurricane Center started issuing advisories on tropical cyclones in the eastern north Pacific. It replaced the previous forecaster, Fleet Weather Central. Also. the Central Pacific Hurricane Center started to issue advisories on tropical cyclones in its area of responsibility this season. It replaced the Joint Hurricane Warning Center.February 2024 These statements need a reliable source See also Tropical cyclones List of Pacific hurricanes Pacific hurricane season 1970 Atlantic hurricane season 1970 Pacific typhoon season 1970 North Indian Ocean cyclone season Australian cyclone seasons: 1969–70, 1970–71 South Pacific cyclone seasons: 1969–70, 1970–71 South-West Indian Ocean cyclone seasons: 1969–70, 1970–71 References 1970 CPHC Archive accessed November 17, 2005 NOAA Monthly Weather Review accessed November 17, 2005 Arizona's tropical cyclones accessed November 17, 2005 External links ATCR Eastern Pacific summary 1970 Pacific hurricane 1970 Category:Pacific hurricane seasons Category:Articles which contain graphical timelines