1990 Pacific hurricane season

Infobox hurricane season
Basin=EPac
Year=1990
Track=1990 Pacific hurricane season map.png First storm formed=May 12, 1990
Last storm dissipated=October 31, 1990
Strongest storm name=Trudy
Strongest storm winds=135
Strongest storm pressure=924
Average wind speed=1
Total depressions=26
Total storms=21
Total hurricanes=16
Total intense=6
Fatalities=0
Da

Inflated=
five seasons=1988, 1989, 1990, 1991, 1992The 1990 Pacific hurricane season officially started on May 15, 1990 in the eastern Pacific, and on June 1, 1990 in the central Pacific, and lasted until November 30, 1990. These dates conventionally delimit the period of each year when most tropical cyclones form in the northeastern Pacific Ocean. However, these bounds were slightly exceded when Hurricane Alma formed on May 12. cite web|author=NOAA|year=1990|title=80columnreport|publisher=AOML|accessdate=2006-12-20|url=http://www.nhc.noaa.gov/tracks1949to2005_epa.txt]

The season was the second most active season behind the 1992 season. Hurricane Alma became the earliest hurricane since the satellite era began, while Trudy was the second most intense east Pacific hurricane at the time. Tropical Storm Rachel made two landfalls in Mexico and brought rain to the United States. Overall, the impact of this season was minimal.cite web|author=Lixion Avila|year=1990|title=Eastern North Pacific Season of 1990|publisher=National Hurricane Center|accessdate=2006-12-20|url=http://ams.allenpress.com/archive/1520-0493/119/8/pdf/i1520-0493-119-8-2034.pdf]

eason Summary

The 1990 eastern North Pacific hurricane season was very active in terms of number of storms that attained at least tropical storm intensity and of Accumulated Cyclone Energy. Also it was very active because it established several tropical storm records for this basin and was marked by several unusually strong hurricanes too. There were 20 named tropical cyclones, four below the record established by the 1992 season two years later, but four more than the long-term average. Sixteen of those named storms, twice the average and four more than the previous record, reached hurricane intensity; only Cristina, Douglas, Aka, Rachel, and Simon did not reach hurricane strength. Six of those hurricanes reached Category 3 intensity or higher on the Saffir-Simpson Hurricane Scale. Furthermore, hurricanes Hernan and Trudy were among the strongest ever observed in this area. Alma became the earliest named tropical cyclone for the eastern Pacific proper. In addition, the eastern Pacific produced four tropical depressions that did not reach tropical storm status.

All of this season's storms and hurricanes developed from westward-moving African waves. With the exception of Marie and Polo, these systems developed between 5° and 15°N, east of the longitude of Baja California in the climatologically favored area for cyclogenesis. After their development, most of the tropical cyclones moved on a west to northwest track and dissipated over cool waters without affecting land. Rachel was the only system to make landfall. Five named tropical cyclones moved over or very near Socorro Island located about 450 km south of Cabo San Lucas.One cyclone, a tropical storm, formed in the Central Pacific and eventually crossed the dateline before dissipating. cite web|author=Lixion Avila|year=1990|title=Eastern North Pacific Season of 1990|publisher=National Hurricane Center|accessdate=2006-12-20|url=http://ams.allenpress.com/archive/1520-0493/119/8/pdf/i1520-0493-119-8-2034.pdf]

torms

Twenty-four tropical cyclones, including four tropical depressions that failed to attain tropical storm status, developed in the Eastern Pacific Ocean and two tropical cyclones, including one tropical depression that did not strengthen into a tropical storm, formed in the Central Pacific Ocean in 1990.

Hurricane Alma

Infobox Hurricane Small
Basin=EPac


Track=Alma 1990 track.pngFormed=May 12
Dissipated=May 18
1-min winds=75
Pressure=979A tropical wave emerged from Africa on April 29. It then moved across the Atlantic, crossed northern South America, and entered the Pacific Ocean on May 9. Convection started to increase with the wave just to the south of Panama. The wave moved westward and continued to become better organized over the next few days. On May 12, the wave had become organized enough and was designated Tropical Depression One-E.cite web|author=Robert A. Case|year=1990|title=Hurricane Alma Prelim 1 |publisher=National Hurricane Center |accessdate=2006-12-01 |url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/alma/prenhc/prelim01.gif]

Tropical Depression One-E moved slowly to the northwest while strengthening very little because of easterly wind shear. The depression was upgraded to Tropical Storm Alma on May 14. Alma quickly strengthened and was near hurricane force by the morning of May 15. A few hours later, Alma was upgraded to a hurricane. Hurricane Alma reached it's peak intensity early on May 16 with sustained winds of 85 mph (135 km/h). Alma entered an area of southwesterly wind shear caused by an upper-level ridge of high pressure. The increasing shear and cooler water caused Alma to weaken to a tropical storm. On May 17 Alma continued to weaken and became a depression. The next day Alma dissipated well west of mainland Mexico.cite web|author=Mayfield|year=1990|title=Tropical Cyclone Discussion Tropical Depression One-E|publisher=National Hurricane Center|accessdate=2007-11-24|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/alma/tropdisc/tcd1315z.gif] cite web|author=Gerrish|year=1990|title=Tropical Cyclone Discussion Tropical Storm Alma|publisher=National Hurricane Center|accessdate=2007-11-24|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/alma/tropdisc/tcd1503z.gif] cite web|author=NHC|year=1990|title=Alma track 1|publisher=National Hurricane Center|accessdate=2007-11-24|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/alma/opltrack/track1.gif]

Alma became the earliest named storm and hurricane in the satellite era. The storm caused no damage or casualties as it did not effect any land. No watches or warnings were issued for Alma.cite web|author=Robert A. Case|year=1990|title=Hurricane Alma Prelim 2 |publisher=National Hurricane Center |accessdate=2006-12-01 |url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/alma/prenhc/prelim02.gif]

Hurricane Boris

Infobox Hurricane Small
Basin=EPac


Track=Boris 1990 track.pngFormed=June 2
Dissipated=June 8
1-min winds=80
Pressure=977A tropical wave came off the northwest coast of Africa, on May 20. The wave made an uneventful course, as it moved west, across the Atlantic Ocean and Caribbean Sea. However, as it crossed Central America into the warm-watered eastern Pacific Ocean, its cloudiness increased considerably on May 31. cite web|author=Max Mayfield|year=1990|title=Hurricane Boris Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/boris/prenhc/prelim01.gif]

It became Tropical Depression Two-E on June 2, indicated by satellite and ship report analysis. After becoming a depression, 2-E moved in a west to northwestward direction. Upper-level easterly shear limited the amount of the initial strengthening. However, satellites observations later showed an increase in convective banding, and 2-E became Tropical Storm Boris on June 4, convert|435|mi|km southwest of Manhandle. By June 5, Boris was upgraded to a hurricane based on Dvorak intensity analysis, as the system had formed its own anticyclone. The hurricane also began to move more north-northwestward, in response to a trough off of the West Coast of the United States. It also underwent further strengthening, as it reached its peak strength of convert|90|mi/h|km/h|abbr=on, and a minimum air pressure of 977 mbar. The winds in the eyewall of Boris ripped off the sails of the Azzure Dream sailboat. No other direct damages or casualties were reported from Boris.cite web|author=Max Mayfield|year=1990|title=Hurricane Boris Prelim 2|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/boris/prenhc/prelim02.gif] cite web|author=Avila|year=1990|title=Hurricane Boris: Tropical Cyclone Discussion June 3 2031Z|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/boris/tropdisc/tcd0321z.gif]

The hurricane's cloud pattern became longer along its southwest and northeast sectors on June 6, due to an increased amount of shearing. Boris was downgraded to a tropical storm later in the day on June 6. The deep convection of the tropical storm decreased, as Boris moved into areas with even cooler water temperatures. It was downgraded to a tropical depression on June 7, due to these factors. The depression was declared to be dissipated on June 8, as the system was quickly losing its tropical characteristics, though a small circulation of clouds persisted off the northwest coast of Baja California, for a few days.cite web|author=Avila|year=1990|title=Hurricane Boris: Tropical Cyclone Discussion June 8 1421Z|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/boris/tropdisc/tcd0815z.gif]

Boris's remnants brought rain to the Southwest. Despite causing the wettest June in San Diego since records began in 1850, not even an inch of rain fell at that location. [http://www.hpc.ncep.noaa.gov/tropical/rain/boris1990rain.gifHPC Boris Rainfall] ]

Tropical Storm Cristina

Infobox Hurricane Small
Basin=EPac


Track=Cristina 1990 track.pngFormed=June 8
Dissipated=June 16
1-min winds=55
Pressure=994A tropical wave came off the coast of Africa, into the Atlantic Ocean, on May 23. It went across the Atlantic Ocean, with minimal development as it moved westward. The wave moved across Central America into the northeastern Pacific Ocean, where convection organized with the system on June 6. The system became Tropical Depression 3-E on June 8, while convert|800|mi|km south of the southern tip of Baja California, close to tropical storm strength. The depression became Tropical Storm Cristina on June 9.cite web|author=Lixion Avalia|year=1990|title=Tropical Storm Cristina Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/cristina/prenhc/prelim01.gif] cite web|author=Avila|year=1990|title=Tropical Storm Cristina: Tropical Cyclone Discussion June 8 1434Z|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/cristina/tropdisc/tcd0815z.gif]

Cristina had a well established upper-level flow as it was above warm waters during its first few days as a tropical storm however it failed to reach hurricane status, peaking at convert|65|mi/h|km/h|abbr=on. An upper-level anticyclone eventually moved north over Mexico, which caused Cristina to be exposed to easterly shear. For the first few nights after this the convection was intense, but the tropical storm weakened significantly during the daytime. Weak steering currents caused the system to move erratically however Cristina moved northwestward. This placed the storm in cooler waters, and the deep convection of the system went away. On June 14, Cristina diminished to a tropical depression. The low-level circulation of clouds of Tropical Depression Cristina, moved west-northwestward, due to a low-level flow. The depression dissipated on June 16, after a lack of deep convection for 48 hours and no signs of tropical characteristics. No damage or casualties were reported, due to Cristina.cite web|author=Mayfield|year=1990|title=Tropical Storm Cristina: Tropical Cyclone Discussion June 16 2010Z|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/cristina/tropdisc/tcd1621z.gif]

Tropical Storm Douglas

Infobox Hurricane Small
Basin=EPac


Track=Douglas 1990 track.pngFormed=June 19
Dissipated=June 23
1-min winds=55
Pressure=992A tropical wave moved off the northwest coast of Africa on June 5. It continued westward through the northern tropical Atlantic Ocean and generated an increase in convection shortly while near the Lesser Antilles. This quickly diminished though, when it was moving westward across the Caribbean Sea.cite web|author=Hal Gerrish|year=1990|title=Tropical Storm Douglas Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/douglas/prenhc/prelim01.gif]

The wave entered the northeastern Pacific Ocean on June 16, where it generated an area of increased cloudiness. Organization, which was not apparent previously with the wave, became apparent late on June 18 and early on June 19. Tropical Depression Four-E formed on June 19, when it was convert|200|mi|km south of Acapulco, Mexico, after evidence of low-level circulation for the past 24 hours. 4-E moved in a west-northwest direction, due to a low-level ridge being north of the depression. Satellite analysis indicated that the depression had reached tropical storm force strength, and it was upgraded to Tropical Storm Douglas on June 19, while convert|200|mi|km southwest of Acapulco. Douglas reached peak strength of convert|65|mi/h|km/h|abbr=on on June 21cite web|author=Lawrence|year=1990|title=Tropical Storm Douglas: Tropical Cyclone Discussion June 19 2100Z|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/douglas/tropdisc/tcd1921z.gif]

A tropical storm warning was issued on June 21, from Punta Tejupan to Cabo Corrientes. Tropical Storm Douglas brushed, but missed, the western coast of Mexico. The center of circulation approached within convert|15|mi|km of the coast of Mexico, on June 22. Douglas then began to weaken, because of interaction with the mountainous terrain of Mexico. It was thought when Douglas began to move away from Mexico, that it may have strengthened, due to warm sea temperatures and favorable upper-level conditions. The tropical storm warning was discontinued later on June 22. There was some evidence of strengthening on June 23 however this quickly diminished. Douglas then quickly dissipated early on June 24, while convert|120|mi|km south-southeast of the southern tip of Baja California. No deaths or damage were reported, though the storm caused heavy rains of up to convert|7|in|mm, possibly causing flash flooding or mudslides.cite web|author=Hal Gerrish|year=1990|title=Tropical Storm Douglas Prelim 4|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/douglas/prenhc/prelim04.gif] [ [http://ams.allenpress.com/pdfserv/10.1175%2F1520-0493(1991)119%3C2034:ENPHSO%3E2.0.CO%3B2] Dead link|date=May 2008]

Hurricane Elida

Infobox Hurricane Small
Basin=EPac


Track=Elida 1990 track.pngFormed=June 26
Dissipated=July 2
1-min winds=70
Pressure=990A tropical wave came off the coast of Africa into the eastern Atlantic Ocean, around June 10 or 11. The system moved across the Atlantic and entered into the northeastern Pacific Ocean.cite web|author=Miles Lawrence|year=1990|title=Hurricane Elida Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/elida/prenhc/prelim01.gif]

The wave became a significant tropical system, with cyclonic turning in the lower and middle layers of the system's cloudiness, on June 25. The center of circulation was located convert|300|mi|km south of Acapulco, Mexico. The wave became Tropical Depression 5-E on June 26. The depression quickly strengthened and became Tropical Storm Elida later that day. The track of Elida was west-northwestward to northwestward from June 27 through June 28. Some rainbands moved over the mountainous region of southwestern Mexico, but no flooding, damage, or casualties were reported as a result. Elida continued strengthening and it was upgraded to a hurricane early on June 28 passing directly over Socorro Island later in the day, right as Elida reached peak strength of convert|80|mi/h|km/h|abbr=on, dropping 3.7 inches, 94.4 mm, on the island. Some windows broke also as a result, and minor structural damage was reported as a result on the island.cite web|author=Miles Lawrence|year=1990|title=Hurricane Elida Prelim 2|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/elida/prenhc/prelim02.gif]

A high pressure to the north forced Elida to move more westward, on June 29. Convection began to decrease in the hurricane, as it moved into cooler waters, and it weakened to a tropical storm later in the day. It then weakened to a tropical depression on July 1, and dissipated on July 2.cite web|author=Mayfield|year=1990|title=Hurricane Elida: Tropical Cyclone Discussion July 1 0209Z|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/elida/tropdisc/tcd0103z.gif]

Tropical Depression Six-E

Infobox Hurricane Small
Basin=EPac


Formed=June 29
Dissipated=July 4
1-min winds=30An area of disturbed weather south of Acapulco organized into Tropical Depression Six-E on June 29 and the system began to move northwest. Originally it was expected to reach tropical storm strength but the persistent shear over the system impeded to do so and instead of it, weakened back over the next day. However on July 1 the shear relaxed and the system began to strengthen again, but not for much time because the system could not define its circulation and subsequently dissipated on July 4.cite web|author=National Weather Service|year=1990|title=Tropical Depression Six-E Tropical Discussions|publisher=National Hurricane Center|accessdate=2006-12-20|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/td6e/tropdisc/]

Hurricane Fausto

Infobox Hurricane Small
Basin=EPac


Track=Fausto 1990 track.pngFormed=July 6
Dissipated=July 12
1-min winds=75
Pressure=979A tropical wave came off the northwest coast of Africa on June 19. The wave crossed the Atlantic Ocean and Caribbean Sea, into the warm waters of the northeastern Pacific Ocean, on July 2.cite web|author=Max Mayfield|year=1990|title=Hurricane Fausto Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/fausto/prenhc/prelim01.gif]

The system moved northwards towards the Gulf of Tehuantepec and became Tropical Depression Seven-E early on July 6. The depression moved northwest, and because of deep convection observed on satellite imagery, became Tropical Storm Fausto on July 7, convert|230|mi|km south of Manzanillo, Mexico. A weakly defined eye formed on July 8, and the storm was upgraded to Hurricane Fausto, convert|270|mi|km south of Cabo San Lucas, Mexico. Fausto peaked at convert|85|mi/h|km/h|abbr=on and 979 mbar on July 9. Fausto passed convert|35|mi|km north of Socorro Island causing a northwest wind of convert|40|mi/h|km/h|abbr=on, and at least pouring convert|4.3|in|mm of rain at that location. The hurricane then temporarily weakened, but again reintensified on July 10.cite web|author=Max Mayfield|year=1990|title=Hurricane Fausto Prelim 2|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/fausto/prenhc/prelim02.gif]

However this regaining was short-lived and on the same day, Fausto was downgraded again to a tropical storm, convert|350|mi|km west of Cabo San Lucas. The weakening Fausto moved over continuing cooler waters, and was downgraded to a tropical depression on June 11, convert|600|mi|km west of Cabo San Lucas. The depression finally dissipated on June 13, although a low level circulation of clouds persisted for a few days.

Hurricane Genevieve

Infobox Hurricane Small
Basin=EPac


Track=Genevieve 1990 track.pngFormed=July 10
Dissipated=July 18
1-min winds=90
Pressure=970A tropical wave moved off the coast of Africa on June 25. The wave had a moderate amount of convection coming into the eastern Atlantic Ocean, until it approached the Lesser Antilles, where it lost all signs of its previous convection. The system then moved into the Caribbean Sea and the wave's convection once again sparked, upon reaching the extreme southwestern portion of the sea on July 7.cite web|author=Robert A. Case|year=1990|title=Hurricane Genevieve Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/geneviev/prenhc/prelim01.gif]

The system became better organized, as it moved into the northeastern Pacific Ocean. Based upon satellite imagery, the system was upgraded to Tropical Depression 8-E on July 11. 8-E moved west-northwest, with a good outflow to the north, and gradually strengthen to Tropical Storm Genevieve, later on July 11. Genevieve continued to strengthen, and the storm became Hurricane Genevieve on July 13. The storm entered within convert|20|mi|km of Socorro Island where a sustained wind of convert|44|mi/h|km/h|abbr=on and gust of convert|50|mi/h|km/h|abbr=on were reported, before the equipment on the island failed. Genevieve moved south of a high pressure system centered over the northwestern portion of Mexico. The hurricane began to turn west because of the strengthening and growing of the high pressure system that dominated the western portion of the United States and Mexico and the waters next to these locations. A favorable outflow began to form, as a low pressure developed in the northwest of Genevieve and partially due to an anticyclone, the hurricane reached its peak strength of convert|105|mi/h|km/h|abbr=on and at that time it had a well defined eye in the center of circulation.cite web|author=Robert A. Case|year=1990|title=Hurricane Genevieve Prelim 2|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/geneviev/prenhc/prelim02.gif] cite web|author=|year=1990|title=Hurricane Genevieve: Tropical Cyclone Discussion July 11 1422Z|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/geneviev/tropdisc/tcd1115z.gif]

However, Genevieve began to turn to the northwest, on July 16, into an area with strong wind shear and low water temperatures. The hurricane quickly weakened into a storm on July 17 and then into a tropical depression on July 18. Genevieve was declared dissipated later in the day, and was reduced to a merely circulation of clouds.

Hurricane Hernan

Infobox Hurricane Small
Basin=EPac


Track=Hernan 1990 track.pngFormed=July 19
Dissipated=July 31
1-min winds=135
Pressure=928A tropical wave that moved off the northwest coast of Africa on July 4 passed through the Atlantic Ocean and Caribbean Sea, without much organization taking place.cite web|author=Hal Gerrish|year=1990|title=Hurricane Hernan Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/hernan/prenhc/prelim01.gif]

The system moved across Central America into the northeastern Pacific Ocean, on July 15. Convection increased in the system from July 16 through July 18 and then banding became present within the wave on July 19. Tropical Depression Nine-E formed later that day while convert|490|mi|km southwest of Acapulco, Mexico. During the time 9-E was moving westward, it wasn't clear whether it or trailing tropical depression 10-E would develop as 9-E was in the Intertropical Convergence Zone. Both depressions, however, ultimately developed into tropical storms, and later, hurricanes; even though Hernan's outflow appeared to feel the effects of the strengthening of Iselle temporarily.

Nine-E became Tropical Storm Hernan on July 21 while convert|600|mi|km south of Cabo San Lucas. The tropical storm continued to strengthen and as it moved to the northwest, it became Hurricane Hernan later on July 21. Hernan continued to strengthen and as it passed while convert|125|mi|km southwest of Clarion Island, and convert|220|mi|km south-southwest of Socorro Island. Estimates based on satellite imagery showed that on July 23 Hernan had reached its peak strength of convert|155|mi/h|km/h|abbr=on and minimum pressure of 928 mbar, as the center of circulation was convert|180|mi|km south-southwest of Clarion Island. However, no direct measurements of strength were made of the hurricane. Later, on July 24, was seen a concentric eyewall (one eyewall located inside another) on infrared satellite imagery. This feature is fairly rare in hurricanes, which have been observed on radar and satellite imagery and this is the first time this pattern had been observed on eastern Pacific tropical basin satellite imagery.cite web|author=Hal Gerrish|year=1990|title=Hurricane Hernan Prelim 2|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/hernan/prenhc/prelim02.gif]

Hernan kept Category 4 intensity for 4 more days, and maintained hurricane strength for 6 days overall. The hurricane weakened into a tropical storm on July 28, as it moved over cooler waters. Hernan was on a more westerly course then previously. The low level center of Hernan's clouds became exposed, Hernan's convection decreased and the system moved over even cooler waters. Hernan finally dissipated on early July 31, after a low level circulation was determined to no longer exist and moisture in the middle and upper levels was being pulled away from the remnants.cite web|author=Satchwell|year=1990|title=Hurricane Hernan: Tropical Cyclone Discussion July 31 0216Z|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/hernan/tropdisc/tcd3103z.gif]

Hurricane Iselle

Infobox Hurricane Small
Basin=EPac


Track=Iselle 1990 track.pngFormed=July 20
Dissipated=July 30
1-min winds=105
Pressure=958A tropical wave moved off the coast of Africa, into the eastern Atlantic Ocean, on July 7. The wave moved west, across the tropical basin of the Atlantic, and had some organized thunderstorm activity associated with it. The system had a well defined wind shift, as it passed the island of Barbados, but it was not until it left the Atlantic and Caribbean Sea, that the wave's convection organized.cite web|author=Lixion Avalia|year=1990|title=Hurricane Iselle Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/iselle/prenhc/prelim01.gif}]

The wave entered into the northeastern Pacific Ocean, with concentrated convection and a surface center of circulation, as it was located in waters southeast of Acapulco on July 11. Tropical Depression Ten-E formed on July 20 and it became Tropical Storm Iselle over the next day. Then, the storm strengthened even further, and it was upgraded into Hurricane Iselle on July 22. This strengthening occurred even when this system was located near the more powerful Hurricane Hernan. The hurricane continued to move west-northwest through its lifespan, and reached its peak strength of convert|120|mi/h|km/h|abbr=on on July 25. Iselle track came close to Socorro Island, recording a convert|70|mi/h|km/h|abbr=on sustained wind and heavy rain, also on July 25. This made Iselle the fourth tropical cyclone to move close to the island, during the season.cite web|author=Lixion Avalia|year=1990|title=Hurricane Iselle Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/iselle/prenhc/prelim02.gif}] cite web|author=Lixion Avalia|year=1990|title=Hurricane Iselle Prelim 3|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/iselle/prenhc/prelim03.gif}]

Iselle weakened the days following reaching its peak strength. The hurricane was downgraded to a tropical storm on July 28 and subsequently into a tropical depression on July 30. The depression dissipated later that day, after moving over cooler waters and losing a low level circulation.cite web|author=Lawrence|year=1990|title=Hurricane Iselle: Tropical Cyclone Discussion July 30 1958Z|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/iselle/tropdisc/tcd3021z.gif]

Tropical Depression Eleven-E

Infobox Hurricane Small
Basin=EPac


Formed=July 24
Dissipated=July 26
1-min winds=25On July 24 a tropical disturbance strengthened into a tropical depression. Due to its nearness to Hurricane Hernan, the development of the depression was hindered, so although intensification was expected it did not do so because of the presence of wind shear from Hernan, finally causing the depression to dissipate on July 26 as it lost its circulation. The remnants were absorbed by Hernan. No damages or casualties were caused by the depression as it was in the middle of the ocean.cite web|author=National Hurricane Center|year=1990|title=Tropical Discussions on TD-11E|publisher=NOAA|accessdate=2006-12-20|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/td11e/tropdisc]

Tropical Storm Aka

Infobox Hurricane Small
Basin=EPac


Track=Aka 1990 track.pngFormed=August 7
Dissipated=August 15
1-min winds=55Tropical Storm Aka was the first and only tropical storm to form in the central North Pacific in the 1990 season. An area of disturbed weather began to organize on August 6 and then the first advisory on tropical depression One-C was issued a day later. The depression rapidly intensified into a tropical storm. The storm continued to move west, south of the Hawaiian Islands and subsequently Tropical Storm Aka peaked on August 10 at 60 mph. Then, the storm continued to move west as it approached to Johnston Island however little affected the weather to the island. After this, the storm crossed the International Date Line on August 13. cite web|author=Central Pacific Hurricane Center|year=1990|title=akareport|publisher=National Weather Service|accessdate=2006-12-19|url=http://www.prh.noaa.gov/cphc/summaries/1990.php] Finally, it weakened back to a depression and it dissipated two days later on August 15. cite web|author=UNISYS|year=1990|title=akatrack|publisher=UNYSIS|accessdate=2006-12-19|url=http://weather.unisys.com/hurricane/e_pacific/1990/AKA/track.dat]

Tropical Depression Two-C

Infobox Hurricane Small
Basin=EPac


Formed=August 10
Dissipated=August 13
1-min winds=30Tropical Depression Two-C was the second and last cyclone to form in the North Central Pacific Ocean. The depression formed from a tropical disturbance that became much better organized on the night of August 10. The tropical depression moved in a west northwest direction for the next 18 hours and then changed to a south of west track next morning. Then, it continued to move toward the west-southwest for the next day and then turned toward the southwest. After this, the storm started to weaken until it dissipated on August 13 about convert|600|mi|km south-southeast of Hilo, Hawaii.cite web|author=Central Pacific Hurricane Center|year=1990|title=Tropical Depression 2-C report|publisher=NOAA|accessdate=2006-12-20|url=http://www.prh.noaa.gov/cphc/summaries/1990.php]

Tropical Depression Twelve-E

Infobox Hurricane Small
Basin=EPac
Formed=August 17
Dissipated=August 19
1-min winds=30A persistent area of convection southwest of Puerto Vallarta became better organized as it strengthened into Tropical Depression 12-E on August 17 and began to move northwest. The intensification of the system was developing in a very slow pace because it was embedded within the ITCZ and for the next day it did not strengthen at all. On early August 19 it was expected to intensify but due to easterly shear caused the system to weaken and finally dissipate later on day. No damages or fatalities were caused by this depression.cite web|author=Case, Mayfield, Lawrence, Avila and Gerrish|year=1990|title=Tropical Discussions on 12-E|publisher=NOAA|accessdate=2006-12-20|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/td12e/tropdisc/]

Hurricane Julio

Infobox Hurricane Small
Basin=EPac


Track=Julio 1990 track.pngFormed=August 17
Dissipated=August 24
1-min winds=100
Pressure=960A tropical wave moved off the western coast of Africa on August 5. It moved across the Atlantic Ocean and Caribbean Sea, without becoming well organized.cite web|author=Miles Lawrence|year=1990|title=Hurricane Julio Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/julio/prenhc/prelim01.gif]

The system entered the northeastern Pacific Ocean, and became Tropical Depression Thirteen-E on August 17 while center convert|350|mi|km south of Acapulco, Mexico. 13-E moved on a west-northwestward track and then it became Tropical Storm Julio on August 18 and it subsequently reached hurricane strength on August 19. Julio peaked at convert|115|mi/h|km/h|abbr=on on August 21. The hurricane then began to shift westward and it quickly weakened into a tropical storm on August 23 and then into a tropical depression on August 24, dissipating later that day. No damage was reported from Julio.

Hurricane Kenna

Infobox Hurricane Small
Basin=EPac


Track=Kenna 1990 track.pngFormed=August 21
Dissipated=August 30
1-min winds=75
Pressure=980A tropical wave moved off the coast of Africa on August 9. As the wave moved westward, it began to show signs of organization and became Tropical Depression Seven, while in the central portion of the Atlantic basin, on August 11. Then it strengthened to Tropical Storm Fran on August 13, and then moved through the southern Windward Islands on August 14. Fran dissipated shortly after that, but the tropical wave that remained later moved into the northeastern Pacific Ocean.cite web|author=Robert A. Case|year=1990|title=Hurricane Kenna Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/kenna/prenhc/prelim01.gif]

The wave became Tropical Depression Fourteen-E, while convert|700|mi|km east-southeast of Hurricane Julio. 14-E moved westward for the next several days, following Julio. As Julio weakened ahead of it, 14-E began to increase in strength. 14-E became Tropical Storm Kenna on August 22 and then it strengthened into Hurricane Kenna on August 25, peaking at convert|85|mi/h|km/h|abbr=on the next day. On August 26, a strong frontal trough eroded the effects of the high pressure to the north, and Kenna began to turn northward during the next few days. The hurricane then began to weaken in response to both cooler water and increasing wind shear, which sheared the convection in the northern portion of the circulation. Kenna weakened back to tropical storm strength on August 28, then into a tropical depression on August 29. It eventually dissipated next day as indicated by satellite imagery. There were no damages or casualties reported from Hurricane Kenna.cite web|author=Avila|year=1990|title=Hurricane Kenna: Tropical Cyclone Discussion August 28 1423Z|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/kenna/tropdisc/tcd2815z.gif] cite web|author=Avila|year=1990|title=Hurricane Kenna: Tropical Cyclone Discussion August 30 2020Z|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/kenna/tropdisc/tcd3021z.gif]

Hurricane Lowell

Infobox Hurricane Small
Basin=EPac


Track=Lowell 1990 track.pngFormed=August 23
Dissipated=September 1
1-min winds=65
Pressure=986A tropical wave moved off the northwestern coast of Africa, into the Atlantic Ocean, on August 11. After moving across the Atlantic and Caribbean Sea, the system moved into the Intertropical Convergence Zone of the northeastern Pacific Ocean.cite web|author=Max Mayfield|year=1990|title=Hurricane Lowell Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/lowell/prenhc/prelim01.gif]

The cloudiness moved northward toward the Gulf of Tehuantepec on August 22. Tropical Depression Fifteen-E formed on August 23, convert|260|mi|km southeast of Acapulco, Mexico as satellite imagery indicated it. 15-E moved west-northwestward and was upgraded to Tropical Storm Lowell, convert|190|mi|km south-southwest of Puerto Vallarta, on August 25. Then, the storm began to turn more westward and was upgraded to Hurricane Lowell on August 27, convert|250|mi|km southwest of Cabo San Lucas. Later, the hurricane began to temporarily turn west-southwest, due to a ridge strengthening to the north of Lowell.

The deep convection then began to weaken and Lowell was downgraded back to tropical storm status on August 28. The tropical storm then turned to a north-northwestward track as Lowell began to pass over cooler waters. On August 31, it was downgraded to a tropical depression, with only minimal amounts of deep convection remaining within the circulation. Finally, Lowell dissipated on September 1, though a low-level circulation of clouds could be seen on satellite imagery for the next few days. No damage or casualties was reported as a result of Lowell.cite web|author=Max Mayfield|year=1990|title=Hurricane Lowell Prelim 2|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/lowell/prenhc/prelim02.gif]

Hurricane Marie

Infobox Hurricane Small
Basin=EPac


Track=Marie 1990 track.pngFormed=September 7
Dissipated=September 21
1-min winds=120
Pressure=944A tropical wave moved off the northwestern coast of Africa on August 16. The wave moved west through the Atlantic Ocean, without generating much convection through most of its crossing, though when it was near the Lesser Antilles. The convection was short-lived however, and it moved through the rest of the Caribbean Sea uneventfully.cite web|author=Hal Gerrish|year=1990|title=Hurricane Marie Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/marie/prenhc/prelim01.gif]

It moved across Central America and into the northeastern Pacific Ocean, on August 29. Convection with the system increased as it was south of the Gulf of Tehuantepec. The wave's convection however remained rather isolated, as the system moved northwest parallel to the southwest coast of Mexico. The system became Tropical Depression Sixteen-E on September 7, with the center of circulation convert|570|mi|km southwest of Clarion Island and convert|220|mi|km south-southwest of Socorro Island. The location of the depression formation was west of where tropical cyclones generally form in the northeastern Pacific Ocean.

A weak ridge controlled the movement of Sixteen-E instead of the normal high pressure in the northeastern Pacific Ocean. The steering currents of the tropical depression were therefore weaker then usual. Then, tropical depression 16-E became Tropical Storm Marie on September 8. The tropical storm eventually developed into Hurricane Marie on September 9, convert|840|mi|km south-southwest of Clarion Island. Marie continued its strengthening, and reached its peak strength of convert|140|mi/h|km/h|abbr=on on September 11.

Then, Marie crossed into the central North Pacific on September 14 as it was a Category 3 hurricane on the Saffir-Simpson Hurricane Scale with maximum sustained winds of 110 mph. After this crossing the hurricane began to weaken and on September 17 the hurricane eventually diminished to tropical storm status. An anticyclone was developing near the tropical storm for the next day and Marie began to steer toward the west-southwest hence it weakened into a depression on September 19 and dissipated two days later near the Hawaiian coast. No casualties or damages were caused by Marie.cite web|author=Central Pacific Hurricane Center|year=1990|title=Marie Central Pacific|publisher=National Weather Service|accessdate=2006-12-21|url=http://www.prh.noaa.gov/cphc/summaries/1990.php]

Hurricane Norbert

Infobox Hurricane Small
Basin=EPac


Track=Norbert 1990 track.pngFormed=September 10
Dissipated=September 19
1-min winds=70
Pressure=983A tropical wave moved off the coast of Africa, across the Atlantic Ocean and Caribbean Sea. The wave continued westward and into the northeastern Pacific Ocean.cite web|author=Lixion Avila|year=1990|title=Hurricane Norbert Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/norbert/prenhc/prelim01.gif]

Tropical Depression Seventeen-E formed on September 10, while located convert|660|mi|km south-southwest of Cabo San Lucas, Mexico. 17-E became better organized and became Tropical Storm Norbert later in the day. However, it remained fairly unorganized for a few days. On September 12, Norbert began to interact with Tropical Depression Eighteen-E, as they were located convert|140|mi|km apart, and began to have Fujiwara interaction. After cycling around each other, 18-E was absorbed by the tropical storm, and Norbert began to strengthen as it moved north-northwestward. The tropical storm was upgraded to Hurricane Norbert on September 14, and formed an eye on September 15, reaching peak strength of convert|80|mi/h|km/h|abbr=on that day, changing to a westward motion.

Norbert then began to weaken, and shifted back to a northwestward motion. It was downgraded to a tropical storm later on September 15, and then to a tropical depression on September 18 as it was moving over increasingly cooler waters of the Pacific. Norbert finally dissipated on September 19, after losing all deep convection.cite web|author=Pasch|year=1990|title=Hurricane Norbert: Tropical Cyclone Discussion September 19 2008Z|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/norbert/tropdisc/tcd1921z.gif]

Tropical Depression Eighteen-E

Infobox Hurricane Small
Basin=EPac


Formed=September 11
Dissipated=September 12
1-min winds=30On September 12 a tropical depression formed southwest of Cabo San Lucas very near of Norbert, hence the development of this depression was hindered. Later that day it was forecast that this depression will absorb Norbert. But later on the day, contrary to all forecasts, Norbert absorbed this system hence the final advisory of this system was issued the same night.cite web|author=Avila, Lawrence, Mayfield and Pasch|year=1990|title=Tropical Discussions on 18-E|publisher=NOAA|accessdate=2006-12-20|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/td18e/tropdisc/]

Hurricane Odile

Infobox Hurricane Small
Basin=EPac


Track=Odile 1990 track.pngFormed=September 23
Dissipated=October 2
1-min winds=125
Pressure=935A tropical wave move off the coast of Africa, into the Atlantic Ocean, on September 5. The system then moved west across the Atlantic waters, the Caribbean Sea and eventually into the Pacific Ocean. As it did however, the system was not very apparent on satellite imagery, from September 16 to September 19.cite web|author=Miles Lawrence|year=1990|title=Hurricane Odile Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/odile/prenhc/prelim01.gif] ]

An area of convection entered into the northeastern Pacific Ocean, as it was a few hundred miles south of Acapulco, Mexico. On September 2, Tropical Depression Nineteen-E formed from this convection, as it was convert|650|mi|km south-southeast from the southern tip of Baja California. 19-E moved on a west-northwestward track, due to a strong high pressure system being located directly north of it. On this track it developed swiftly, and was upgraded to Tropical Storm Odile on September 24. Odile continued to strengthen, as it reached hurricane strength on September 25 and peaked at convert|145|mi/h|km/h|abbr=on on September 26.

The hurricane maintained peak intensity for the next day, when it began to turn more northwestward in response to the high-pressure weakening to its north and eventually began to weaken. Odile continued to weaken, as it began to move over cooler waters on September 28. The hurricane weakened to tropical storm status on September 29, as it slowly progressed northward. Odile fell back to tropical depression status on September 30, as it lost deep convection, and was steered southwestward by low-level flows. The depression voided of deep convection dissipated in open waters on October 2 as a remaining low-level circulation of clouds that continued on a southwestward course. No casualties or damages were reported as a result of Odile.cite web|author=Mayfield|year=1990|title=Hurricane Odile: Tropical Cyclone Discussion September 30 2013Z|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/odile/tropdisc/tcd3021z.gif]

Hurricane Polo

Infobox Hurricane Small
Basin=EPac


Track=Polo 1990 track.pngFormed=September 28
Dissipated=October 1
1-min winds=65
Pressure=987Polo originated from the same tropical wave that moved off the Africa coast on September 2 and formed Tropical Storm Isidore in the Atlantic basin. Part of this wave remained disorganized and on September 10 reached the Lesser Antilles. Little convection was apparent during its trek across the Caribbean. A few days later, on September 14 the system increased in convection as it was moving to the west, approaching Central America. Then, after nearing the Mexican coast on September 18, the southern extent of the wave crossed into the Pacific Ocean. cite web|author=Robert A. Case|year=1990|title=Hurricane Polo Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-19|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/polo/prenhc/prelim01.gif]

After crossing into the basin, it moved westward and increased more in convection for all the following week. After several days of development, the first advisory on Tropical Depression Twenty-E was issued on September 28. Initially the depression drifted toward the west-northwest. However a rather large through located to the west of Polo turned the system to the north-northwest on September 29. Thereafter, Polo started a rapid intensification and on early September 30 reached hurricane strength, peaking at convert|75|mi/h|km/h|abbr=on. But since Polo was a very small system, shear did not take too much time to destroy it and on October 1 the system fell again to storm strength as it was crossing into the north Central Pacific basin. It finally dissipated later that day. cite web|author=Robert A. Case|year=1990|title=Hurricane Polo Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-19|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/polo/prenhc/prelim01.gif]

There were no casualties or damages caused by Polo. cite web|author=Robert A. Case|year=1990|title=Hurricane Polo Prelim 2|publisher=National Hurricane Center|accessdate=2006-12-19|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/polo/prenhc/prelim01.gif]

Tropical Storm Rachel

Infobox Hurricane Small
Basin=EPac


Track=Rachel 1990 track.pngFormed=September 27
Dissipated=October 3
1-min winds=55
Pressure=994Around two weeks prior to Tropical Depression Twenty One-E forming in the East Pacific, an associated wave was on the coast of Northwest Africa. A loosely-defined tropical wave entered the eastern Pacific Ocean on the first hours of September 23. Cloudiness became concentrated with the system, south of the Gulf of Tehuantepec, on September 25. A tropical wave formed Tropical Depression Twenty One-E on September 27, convert|200|mi|km south of Acapulco, Mexico. The depression developed slowly, and it wasn't until September 30 when it became a tropical storm, convert|500|mi|km south of Cabo San Lucas, Mexico. As Rachel continued its northwesterly track, a low over California steered it to the north. Rachel recurved and accelerated to an increasingly forward speed. A tropical storm watch, later upgraded to a tropical storm warning, was issued for the southern portion of Baja Califorina, south of La Paz. Rachel crossed the southern tip of the Baja California Peninsula on October 2. A tropical storm watch was initially issued for the Mexican state of Sinaloa, from Los Mochis southward. This was later upgraded to a tropical storm warning too, but it was changed from Los Mochis south to Mazatlán. Then, the center of circulation crossed the Gulf of California and made landfall in the state of Sinaloa midway between Los Mochis and Culiacán. Making Rachel the first, and only, system to make landfall in this season.cite web|author=Max Mayfield|year=1990|title=Tropical Storm Rachel Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/rachel/prenhc/prelim01.gif] cite web|author=Max Mayfield|year=1990|title=Tropical Storm Rachel Prelim 4|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/rachel/prenhc/prelim04.gif] cite web|author=Mayfield|year=1990|title=Tropical Storm Rachel: Tropical Cyclone Discussion October 2 2357Z|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/rachel/public/tcp0300z.gif]

Rachel decayed rapidly over land, and its remnants continued accelerating over Texas until they lost their identity. The last public advisory on the depression was issued on October 2, and dissipated thereafter. No reports of damage or casualties were received from Mexico. In Texas, Rachel's remnants caused heavy rain. Flooding occurred in the Big Bend area.cite web|author=Max Mayfield|year=1990|title=Tropical Storm Rachel Prelim 2|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/rachel/prenhc/prelim02.gif]

Tropical Storm Simon

Infobox Hurricane Small
Basin=EPac


Track=Simon 1990 track.pngFormed=October 9
Dissipated=October 14
1-min winds=60
Pressure=990A weakly defined tropical wave moved off the northwest coast of Africa on September 20. The wave moved across the northern portion of the Atlantic basin, without organizing much more than its original organization. The system then crossed the northern portion of South America, without gaining much more convection, and into the Pacific Ocean.cite web|author=Hal Gerrish|year=1990|title=Hurricane Simon Prelim 1|publisher=National Hurricane Center|accessdate=2006-12-01|url=http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/simon/prenhc/prelim01.gif]

The wave moved into the northeastern Pacific waters, off the coast of Colombia, on September 30. As the wave passed over southern Central America, rain bands and cloudiness increased with the system from October 1 to October 3. However this was short-lived, as it mixed with cloudiness in the Intertropical Convergence Zone, from October 4 to October 6. The ITCZ moved northward and the system pushed forward, on October 7 and October 8. Clear signs of organization were seen within the system, contained within the ITCZ, on October 18. Tropical Depression Twenty Two-E formed on October 9, based on observations from satellite imagery, convert|500|mi|km south of Cabo San Lucas, Mexico. 22-E was upgraded to Tropical Storm Simon on October 10, as it was located convert|525|mi|km south-southwest of Cabo San Lucas. Due to a high pressure system to the north-northwest, Simon continued on a west-northwestward path. The tropical storm continued to strengthen to its peak strength of convert|70|mi/h|km/h|abbr=on, late on October 11.

Simon then began to pass over cooler waters, began to lose its intensity, and weakened to tropical depression strength on October 13. The depression moved on a westward course, and the low-level circulation was displaced from its deep convection over the next day. Simon then moved in a general westward direction and dissipated early on October 15, in the open waters of the Pacific.

Hurricane Trudy

Infobox Hurricane Small
Basin=EPac


Track=Trudy 1990 track.pngFormed=October 16
Dissipated=November 1
1-min winds=135
Pressure=924A tropical wave formed a depression on October 6. It slowly developed, and finally reached hurricane intensity on October 18. Then, Trudy entered a favorable environment and explosively intensified, peaking on October 20. At that time, a trough drifted Trudy north. The trough also increased shear, which substantially weakened the hurricane. The trough outran the storm however, it was replaced by a ridge. The ridge returned favorable conditions, and Trudy reintensified into a Category 4 and resumed its westerly path. Then, another trough came along. This pulled Trudy north, and sheared the hurricane apart. The cyclone dissipated on November 1. Eventually, some of its moisture spread over parts of Mexico and the United States.

Except for Socorro Island, Trudy had no impact on land. The island reported hurricane force winds for seven hours. Trudy also had an unusually large eye, which reached 50 n mi in diameter at that point.

At the time, Trudy was the second-most intense east Pacific hurricane (behind 1973's Ava). It was also the strongest October storm. While it is no longer that high on the all-time intensity list for the east Pacific, Trudy remains as the ninth-strongest Pacific hurricane overall and the second strongest October storm, behind Kenna of the 2002 season.

Hurricane Vance

Infobox Hurricane Small
Basin=EPac


Track=Vance 1990 track.pngFormed=October 21
Dissipated=October 31
1-min winds=85
Pressure=975An area of disturbed weather, possibly related to a tropical wave, organized into Tropical Depression Twenty Four-E on October 21. It strengthened into Tropical Storm Vance early on October 23 and then into a hurricane two days. Vance moved parallel to the west coast of Mexico and approached the southern tip of the Baja California Peninsula. There, a high pressure area blocked Vance's path. The cyclone moved in a small clockwise loop, which is highly unusual in the east Pacific, for two days. During the loop, Vance encountered wind shear and cool waters stirred up by it and Trudy. Vance weakened to a tropical storm on October 27 and a depression on October 30. The cyclone dissipated late on October 31. The formation of Vance, the season's 20th tropical storm, made 1990 the busiest season since 1985.

Accumulated Cyclone Energy (ACE) Rating

The table on the right shows the ACE for each storm in the season. ACE is, broadly speaking, a measure of the power of the hurricane multiplied by the length of time it existed, so storms that last a long time, as well as particularly strong hurricanes, have high ACEs. ACE is only calculated for full advisories on tropical systems at or exceeding 34 knots (39 mph, 63 km/h) or tropical storm strength.

The figures in parentheses are for storms in the Central Pacific basin west of 140°W; those not in parenthesis are for the Eastern Pacific basin.

The cumulative ACE for the Eastern Pacific this season fell within the official "Above Normal" grading, being one of the most active. This occurred because the season had many intense storms that lasted for a long period of time. Also it is important to note that this is the second highest ACE, only behind the 1992 Pacific hurricane season.cite web|author=NOAA|year=1990|title=80columnreport|publisher=AOML|accessdate=2006-12-20|url=http://www.nhc.noaa.gov/tracks1949to2005_epa.txt]

1990 storm names

The following names were used for named storms that formed in the eastern Pacific in 1990. No names were retired, so it was used again in the 1996 season. This is the same list used for the 1984 season. Storms were named Trudy and Vance for the first time in 1990. Names that were not assigned are marked in gray.

One name from the Central Pacific list was used - Aka. It was the first usage for that name.

ee also

*List of Pacific hurricanes
*List of Pacific hurricane seasons
*1990 Atlantic hurricane season
*1990 Pacific typhoon season
*1990 North Indian Ocean cyclone season
*Southern Hemisphere tropical cyclone seasons: 1989–90, 1990–91

References

External links

* [http://www.nhc.noaa.gov/archive/storm_wallets/epacific/ep1990/ NHC 1990 Pacific hurricane season archive]
* [http://www.prh.noaa.gov/cphc/summaries/1990.php Central Pacific Hurricane Center archive]
* [http://www.nhc.noaa.gov/tracks1949to2005_epa.txt List of storms with ACE calculations]
* [http://ams.allenpress.com/archive/1520-0493/119/8/pdf/i1520-0493-119-8-2034.pdf 1991 North Eastern Pacific hurricane season summary]