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Hurricane Eta
Category 4 major hurricane (SSHWS/NWS)
Map plotting the track and the intensity of the storm, according to the Saffir–Simpson scale
FormedOctober 31, 2020
DissipatedNovember 14, 2020
(Extratropical after November 13)
Highest winds1-minute sustained: 150 mph (240 km/h)
Lowest pressure923 mbar (hPa); 27.26 inHg
Areas affectedJamaica, Cayman Islands, Nicaragua, Honduras, Guatemala, Costa Rica, Belize, El Salvador, Panama, Mexico, Cuba, The Bahamas, Western Florida, East Coast of the United States
Part of the 2020 Atlantic hurricane season

The lifetime of Hurricane Eta lasted for 14 days. The disturbance that would become Eta originated from two tropical waves. On October 29, the National Hurricane Center (NHC) began monitoring the waves as they merged together in the Eastern Caribbean. The system steadily organized and on October 31, it was designated Tropical Depression Twenty-Nine. On November 1, based on satellite intensity estimates, the depression became Tropical Storm Eta. Eta rapidly intensified later that day, reaching hurricane status by November 2 as it slowed down. Rapid intensification continued, and Eta intensified into a Category 4 hurricane at 21:00 UTC the next day. Eta developed a clear pinhole eye, and simultaneously reached its peak intensity of 150 mph (240 km/h) and a pressure of 923 mbar (27.26 inHg) at 06:00 UTC on November 3. Later, the storm began an eyewall replacement cycle, which caused it to weaken gradually. It completed the cycle just as it made landfall at 21:00 UTC south of Puerto Cabezas, Nicaragua with winds of 140 mph (220 km/h) and a pressure of 940 mbar (27.73 inHg). Eta rapidly weakened over land while moving slowly westward, and was downgraded to a tropical storm on November 4. The next day, Eta weakened to a tropical depression, and its low-level circulation center became very poorly defined.

Late on November 6, Eta re-emerged into the Western Caribbean Sea near Belize. The next day, Eta became a tropical storm again due to a center reformation. Despite encountering strong wind shear, the storm continued to strengthen and had sustained winds of 65 mph (105 km/h) and a pressure of 991 mbar (29.27 inHg) by November 8. Eta held its strength before making landfall in Cuba's Sancti Spíritus Province at 09:00 UTC. Early on November 9, Eta made its third landfall on the Lower Matecumbe Key in the Florida Keys at the same intensity as its Cuban landfall. Due to a large amount of dry air, Eta's low-level center became exposed and convection dwindled. Eta was eventually able to repel the dry air, and it began re-strengthening in the Gulf of Mexico. As the storm meandered off the Western Cuban coast, its center then reformed under its convective mass and became better organized as it executed a counter-clockwise loop and approached the west coast of Florida. On November 11, Eta restrengthened back into a minimal hurricane as an eye feature appeared on microwave radar images. However, another onrush of dry air rapidly eroded its structure and caused its eye feature to dissipate, weakening Eta back to tropical storm strength a few hours after it attained hurricane intensity. The system turned further east and made landfall near Cedar Key, Florida at 09:20 UTC on November 12, possessing winds of 50 mph (85 km/h). The storm further degraded and weakened over land as it accelerated north-northeastward, eventually emerging over the waters of the Atlantic near the Florida/Georgia border at 18:00 UTC. It fluctuated in intensity as it became extratropical early on November 13.

Origin

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Tropical Depression Twenty-Nine three hours before its designation on October 31.

At 15:00 UTC on October 28, the National Hurricane Center (NHC) began monitoring the Southwestern Caribbean for the expected development of a broad area of low pressure within the following few days.[1] At 12:00 UTC on October 29, the area of focus shifted to two merging tropical waves moving into the Eastern Caribbean that were expected to enter the region.[2] The disturbance steadily moved westward into a more favorable upper-level environment and very warm waters.[3] This allowed it to become better organized going into October 31, although there was some question as to whether it had formed a well-defined low-level circulation (LLC).[4][5] However, by 21:00 UTC that day, satellite and microwave imagery confirmed that an LLC had formed and the NHC began issuing advisories on Tropical Depression Twenty-Nine.[5][6] At 03:00 UTC on November 1, the system intensified into Tropical Storm Eta.[7] Continuing westward in response to a low- to mid-level ridge that extended from the subtropical Atlantic southwestward to Cuba and The Bahamas, Eta slowly organized throughout the day as a central dense overcast (CDO) began to form atop its center.[8]

Rapid intensification and Central America landfall

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Hurricane Eta nearing peak intensity early on November 3.

After remaining at minimal tropical storm strength for 15 hours, Eta began to explosively intensify, reaching hurricane status at 09:00 UTC on November 2.[9] Six hours later, the storm strengthened into a high-end Category 2 hurricane as a small pinhole eye became apparent in visible satellite imagery.[10] Eta then reached Category 3 status at 18:00 UTC before becoming a Category 4 hurricane three hours later, with prolific lightning being observed in its eyewall.[11][12] By this time, Eta had begun to slow down and turn west-southwestward in response to a mid-level ridge over the south-central United States.[12] At 03:00 UTC on November 3, a Hurricane Hunter aircraft found the system still rapidly intensifying with maximum sustained winds of 150 mph (240 km/h) and a pressure of 927 mbar (hPa; 27.38 inHg) as its forward speed continued to decrease.[13] According to the NHC, the Regional Specialized Meteorological Center for the Atlantic, Eta maintained its peak winds as it reached its lowest recorded pressure of 923 mbar (hPa; 27.26 inHg) at 06:00 UTC, thus marking its peak intensity as a high-end Category 4 hurricane.[14] However, it was reported by The Washington Post that several meteorologists believed Eta peaked as a Category 5 hurricane based on satellite imagery estimates as well as a lack of aircraft observations due to several mechanical issues.[15] Despite remaining in a favorable environment, Eta began to weaken six hours after its peak intensity due to an eyewall replacement cycle, which it completed just as it made landfall at 21:00 UTC south of Puerto Cabezas, Nicaragua, with winds of 140 mph (225 km/h) and a pressure of 940 mbar (hPa; 27.76 inHg).[16] Land interaction caused Eta to rapidly weaken as it moved slowly westward after landfall with its eye disappearing and its central convection weakening.[17] It fell below major hurricane status just three hours after landfall at 00:00 UTC on November 4.[18] Eta continued weaken rapidly, dropping to tropical storm status at 09:00 UTC,[19] and to a tropical depression at 00:00 UTC on November 5.[20]

Reintensification and Cuba and first Florida landfalls

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Eta reintensifying in the Caribbean Sea on November 7.

Despite becoming extremely disorganized, Eta maintained its low-level circulation and began gradually turning northeastward, eventually moving back over the Caribbean Sea on November 6 and accelerating due to the influence of a developing mid- to upper-level trough over the Gulf of Mexico.[21] On November 7, following a couple of center reformations, the system became better organized and re-strengthened into a tropical storm at 15:00 UTC on November 7.[22][23][24] Despite the continued effects of strong wind shear, the storm continued to strengthen throughout the day and reached a secondary peak intensity with winds of 65 mph (100 km/h) and a pressure of 991 mbar (hPa; 29.27 inHg) at 00:00 UTC on November 8.[25] It then held its strength and decelerated slightly before making landfall on the south central coast of Cuba at 09:00 UTC.[26] Eta weakened slightly after making landfall in Cuba's Sancti Spíritus Province, but this was short-lived as it quickly moved back over water in the Atlantic Ocean and began to re-strengthen again as it turned sharply northwestward around the northeastern side of an upper-level low that has formed over the extreme northwestern Caribbean Sea near the Isle of Youth.[27] Eta briefly gained a mid-level eye feature before dry air and wind shear stripped the center of most of its convection, although the storm was able to maintain its intensity as it grew in size and approached South Florida.[28] At 04:00 UTC on November 9, Eta made its third landfall on the Lower Matecumbe Key in the Florida Keys with the same intensity as its Cuban landfall.[29] It then passed just south of the extreme southwestern coast of Florida as it turned westward.[30] Eta then turned southwestward under the influence of a strong deep-layer ridge across the Gulf of Mexico, Florida, and near the US East Coast. This also brought it into an area of even dryer air, causing the storm to weaken and its radius of gale-force winds to shrink.[31][32]

Second Florida landfall and dissipation

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Eta paralleling the west coast of Florida as a Category 1 hurricane on November 11.

Eta's center remained sheared to the west of its convection, but the warm waters of the Gulf of Mexico allowed the storm to begin to re-intensify.[33] Eta than began to accelerate north-northeast around the western periphery of a deep-layer subtropical ridge as its the center reformed under this convection and an eye feature formed.[34] Eta then regained minimal hurricane status at 12:35 UTC on November 11, reaching a fourth and final peak intensity with winds of 75 mph (120 km/h) and a pressure of 983 mbar (hPa; 29.03 inHg).[35] Shortly after its upgrade however, another round of dry air intrusion rapidly eroded the convective pattern and caused the eye feature to dissipate causing Eta to weaken back into a tropical storm for the final time at 18:00 UTC.[36] It continued to slowly weaken as it turned northeastward and made landfall near Cedar Key, Florida at 09:00 UTC on November 12, possessing winds of 50 mph (85 km/h) and a pressure of 996 mb (29.42 inHg).[37] The storm further degraded and weakened over land as it accelerated north-northeastward, eventually emerging over the waters of the Atlantic near the Florida/Georgia border at 18:00 UTC.[38] It bottomed out with winds of 40 mph (65 km/h) and 1004 mb (29.65 inHg) before restregthening as began its extratropical transition.[39][40] The storm completed its transition on November 13.[41]

See Also

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References

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  1. ^ Robbie Berg (October 28, 2020). Five-Day Graphical Tropical Weather Outlook (Report). National Hurricane Center. Retrieved November 1, 2020.
  2. ^ Robbie Berg (October 28, 2020). Two-Day Graphical Tropical Weather Outlook (Report). National Hurricane Center. Archived from the original on November 9, 2020. Retrieved November 2, 2020.
  3. ^ Jack Beven (October 30, 2020). Two-Day Graphical Tropical Weather Outlook (Report). National Hurricane Center. Retrieved November 2, 2020.
  4. ^ Stacy Stewart and Robbie Berg (October 31, 2020). Two-Day Graphical Tropical Weather Outlook (Report). National Hurricane Center. Archived from the original on November 8, 2020. Retrieved November 2, 2020.
  5. ^ a b Robbie Berg (October 31, 2020). Tropical Depression Twenty-Nine Discussion Number 1 (Report). National Hurricane Center. Retrieved November 1, 2020.
  6. ^ Robbie Berg. Tropical Depression Twenty-Nine Advisory Number 1 (Report). National Hurricane Center. Archived from the original on November 7, 2020. Retrieved November 2, 2020.
  7. ^ Jack Beven (November 1, 2020). Tropical Storm Eta Discussion Number 2 (Report). National Hurricane Center. Archived from the original on November 9, 2020. Retrieved November 1, 2020.
  8. ^ Richard Pasch (November 1, 2020). Tropical Storm Eta Discussion Number 3 (Report). National Hurricane Center. Archived from the original on November 9, 2020. Retrieved November 3, 2020.
  9. ^ Daniel Brown, Amanda Reinhart, and Robbie Berg (November 1, 2020). Tropical Storm Eta Intermediate Advisory Number 4A (Report). National Hurricane Center. Archived from the original on November 9, 2020. Retrieved November 3, 2020.{{cite report}}: CS1 maint: multiple names: authors list (link); Richard Pasch (November 2, 2020). Hurricane Eta Advisory Number 7 (Report). National Hurricane Center. Archived from the original on November 5, 2020. Retrieved November 3, 2020.
  10. ^ Daniel Brown (November 2, 2020). Hurricane Eta Discussion Number 8 (Report). National Hurricane Center. Retrieved November 3, 2020.
  11. ^ Daniel Brown (November 2, 2020). Hurricane Eta Intermediate Advisory Number 8A (Report). National Hurricane Center. Archived from the original on November 9, 2020. Retrieved November 2, 2020.; "Eta Intensifies Into One of Most Intense November Hurricanes on Record Ahead of Catastrophic Central America Hit". The Weather Channel. November 2, 2020. Archived from the original on November 3, 2020. Retrieved November 3, 2020.
  12. ^ a b Daniel Brown and Robbie Berg (November 2, 2020). Hurricane Eta Discussion Number 9 (Report). National Hurricane Center. Archived from the original on November 9, 2020. Retrieved November 2, 2020.
  13. ^ Stacy Stewart (November 3, 2020). Hurricane Eta Discussion Number 10 (Report). National Hurricane Center. Retrieved November 3, 2020.; Doyle Rice (November 2, 2020). "Hurricane Eta gaining historic strength, may be Category 5 when it hits Central America. Deadly landslides, flooding possible". USA TODAY. Archived from the original on November 3, 2020. Retrieved November 3, 2020.
  14. ^ Richard Pasch (November 3, 2020). Hurricane Eta Intermediate Advisory Number 10A (Report). Miami, Florida: National Hurricane Center. Retrieved November 5, 2020.
  15. ^ Cappucci, Matthew. "Hurricane Eta exploded before hitting Nicaragua, but we may never know how strong it was". Washington Post. ISSN 0190-8286. Archived from the original on November 6, 2020. Retrieved 2020-11-06.
  16. ^ Daniel Brown (November 3, 2020). Hurricane Eta Discussion Number 12 (Report). National Hurricane Center. Archived from the original on November 9, 2020. Retrieved November 3, 2020.; Daniel Brown (November 3, 2020). Hurricane Eta Advisory Number 13 (Report). National Hurricane Center. Archived from the original on November 4, 2020. Retrieved November 3, 2020.; Daniel Brown (November 3, 2020). Hurricane Eta Discussion Number 13 (Report). National Hurricane Center. Retrieved November 3, 2020.
  17. ^ "Hurricane Eta Discussion Number 14". www.nhc.noaa.gov. Archived from the original on November 9, 2020. Retrieved 4 November 2020.; "Tropical Storm Discussion Number 15". www.nhc.noaa.gov. Archived from the original on November 9, 2020. Retrieved 4 November 2020.
  18. ^ "Hurricane Eta Intermediate Advisory Number 13A". www.nhc.noaa.gov. Retrieved 4 November 2020.{{cite web}}: CS1 maint: url-status (link)
  19. ^ "Tropical Storm Eta Advisory Number 15". www.nhc.noaa.gov. Archived from the original on November 9, 2020. Retrieved 4 November 2020.
  20. ^ "Tropical Storm Eta Advisory Intermediate Advisory Number 17A...Corrected". www.nhc.noaa.gov. Retrieved 5 November 2020.{{cite web}}: CS1 maint: url-status (link)
  21. ^ "Tropical Depression ETA". www.nhc.noaa.gov. Archived from the original on November 9, 2020. Retrieved 9 November 2020.
  22. ^ "Tropical Depression ETA". www.nhc.noaa.gov. Retrieved 9 November 2020.
  23. ^ "Tropical Storm ETA". www.nhc.noaa.gov. Retrieved 9 November 2020.
  24. ^ "Tropical Storm ETA". www.nhc.noaa.gov. Retrieved 9 November 2020.
  25. ^ "Tropical Storm ETA". www.nhc.noaa.gov. Retrieved 9 November 2020.
  26. ^ "Tropical Storm ETA". www.nhc.noaa.gov. Archived from the original on November 9, 2020. Retrieved 9 November 2020.
  27. ^ "Tropical Storm ETA". www.nhc.noaa.gov. Archived from the original on November 9, 2020. Retrieved 9 November 2020.; "Tropical Storm ETA". www.nhc.noaa.gov. Archived from the original on November 9, 2020. Retrieved 9 November 2020.
  28. ^ "Tropical Storm ETA". www.nhc.noaa.gov. Retrieved 9 November 2020.
  29. ^ "Tropical Storm ETA". www.nhc.noaa.gov. Archived from the original on November 9, 2020. Retrieved 9 November 2020.; "Tropical Storm ETA". www.nhc.noaa.gov. Archived from the original on November 9, 2020. Retrieved 9 November 2020.
  30. ^ "Tropical Storm ETA". www.nhc.noaa.gov. Retrieved 9 November 2020.
  31. ^ "Tropical Storm ETA". www.nhc.noaa.gov. Archived from the original on November 9, 2020. Retrieved 9 November 2020.
  32. ^ "Tropical Storm ETA". www.nhc.noaa.gov. Archived from the original on November 9, 2020. Retrieved 9 November 2020.
  33. ^ "Tropical Storm ETA". www.nhc.noaa.gov. Retrieved 11 November 2020.
  34. ^ "Tropical Storm ETA". www.nhc.noaa.gov. Retrieved 11 November 2020.
  35. ^ "Hurricane ETA". www.nhc.noaa.gov. Retrieved 11 November 2020.
  36. ^ "Hurricane ETA". www.nhc.noaa.gov. Retrieved 11 November 2020.; "Tropical Storm ETA". www.nhc.noaa.gov. Retrieved 11 November 2020.
  37. ^ Eric Blake (12 November 2020). "Tropical Storm Eta Tropical Cyclone Update". National Hurricane Center. Retrieved 12 November 2020.
  38. ^ "Tropical Storm ETA". www.nhc.noaa.gov. Retrieved 12 November 2020.
  39. ^ "Tropical Storm ETA". www.nhc.noaa.gov. Retrieved 13 November 2020.
  40. ^ "Tropical Storm ETA". www.nhc.noaa.gov. Retrieved 13 November 2020.
  41. ^ "Post-Tropical Cyclone ETA". www.nhc.noaa.gov. Retrieved 13 November 2020.
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