Sunday, August 13, 2017

Jova Weakens to a Tropical Depression; Franklin's Ghost Expected to Weaken Further Through the Weekend

Jonathan Erdman
Published: August 12,2017

Jova has now weakened to a tropical depression while fighting wind shear and cooler water temperatures.  Jova formed in the East Pacific from the remnants of what was once Hurricane Franklin, adding another chapter to what was the Atlantic Basin's first hurricane of 2017.
(MORE: Hurricane Central)
Sounds strange, right? But it's happened before.
Hurricanes and tropical storms typically weaken over land, as they lose the energy source of warm ocean water.
In Franklin's case, the surface circulation was ripped apart by the mountains east of Mexico City.
(MORE: Hurricane Franklin Recap)
However, the remnant spin – called vorticity by meteorologists – and moisture several thousand feet above the surface from Franklin tracked west across Mexico and emerged off Pacific coast early Friday.
This animation shows an ECMWF model forecast of spin (or vorticity) at roughly 10,000 feet above the surface through August 13. Jova's spin is highlighted by the red arrow.

The batch of energy has gathered enough organization and strength to become Jova, which formed 250 miles south of the southern tip of Baja California Friday night.

Infrared Satellite With Franklin's Track History
Since the lower levels of Hurricane Franklin were ripped off by the Mexican mountains, by convention, this new storm has been given a new eastern Pacific name.
Jova is expected to weaken through Sunday due to the cooler waters of the Pacific. Tropical Depression Jova is not expected to impact any land areas.
(MORE: The Weirdest Hurricane and Tropical Storm Tracks)
Track histories of Hurricane Earl and Tropical Storm Javier in early August, 2016.


















2016 Déjà Vu?

Coincidentally, a similar scenario happened almost exactly one year ago, also resulting in an eastern Pacific "J" storm.
Hurricane Earl made landfall in Belize on Aug. 4, 2016.
Less than 24 hours after Earl dissipated, what would later become Tropical Storm Javier formed partially from the remnants of Earl.
Before this, NOAA's Hurricane Research Division says this ghost seeding of a new tropical cyclone in a different basin happened a dozen other times in the Atlantic and eastern Pacific Basins since the mid-1960s, when satellite surveillance of the tropics became routine.
So, on average, this occurs every 3 to 4 years.
In October 2014, the ghost seeding happened in the opposite direction, when eastern Pacific Tropical Storm Trudy made landfall in Mexico. After that, NOAA/HRD says the following occurred:
  • Trudy's circulation dissipated in the mountains of southern Mexico.
  • The remnant moisture and spin aloft helped spawn a tropical depression in the Bay of Campeche.
  • That depression weakened to a tropical low before moving over the Yucatan Peninsula.
  • It regenerated into a depression, then Tropical Storm Hanna before landfalling near the Honduras/Nicaragua border.
In 2001, Iris made a devastating landfall in southern Belize as a Category 4 hurricane after a less-than-five-day cruise through the Caribbean Sea, spun down to a remnant low, then was reborn as Tropical Storm Manuel in the eastern Pacific Ocean, lasting over a week in that basin.
Another case involved 1974's Hurricane Fifi, responsible for anywhere from 3,000 to 10,000 deaths - primarily due to rainfall flooding - in Central America.
(MORE: Tragic History From Tropical Cyclones in Mexico, Central America)
Another bizarre case involved a Category 5 landfall in Belize (Hurricane Hattie in 1961) whose remnant helped form eastern Pacific Tropical Storm Simone.
But there's more.
Simone's remnant then ended up back in the Bay of Campeche, merging with another disturbance to help form Tropical Storm Inga.
To recap, that was Atlantic to eastern Pacific back to Atlantic Basin.
Several have come close, including Javier in 2016, but officially, only twice has an eastern Pacific tropical cyclone spawned from an Atlantic remnant made landfall in Mexico, according to NOAA-HRD:
  • September 1974: Hurricane Orlene (seeded by Atlantic Hurricane Fifi)
  • September 1971: Hurricane Olivia (made landfall in Baja California as a tropical depression; seeded by Atlantic Hurricane Irene)
Jonathan Erdman is a senior meteorologist at and has been an incurable weather geek since a tornado narrowly missed his childhood home in Wisconsin at age 7. Follow him on Facebook and Twitter.

The Weather Company’s primary journalistic mission is to report on breaking weather news, the environment and the importance of science to our lives. This story does not necessarily represent the position of our parent company, IBM.

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