Published: December 31,2015
Tropical Depression Nine-C formed late Wednesday night, U.S. Eastern standard time, just east of the International Date Line, about 1,800 miles southwest of Honolulu, Hawaii.
Moderate wind shear, namely changing wind speed and/or direction with height, is keeping this system rather disorganized, so it remains uncertain whether it will strengthen at all.
If it becomes a tropical storm east of the date line, it will get the next central Pacific name, "Pali." If, however, it persists, but doesn't gain tropical-storm strength until passing west of the date line, it will gain the next western Pacific name, "Nepartak."
It is no immediate threat to land.
(MAP: Wunderground Forecast Path)
What's bizarre is not only the system's formation around the New Year's holiday, but its close proximity to the equator.
Latest Position, Intensity, Movement
Lowry says the previous record holder was Hurricane Ekeka at 4.2 degrees north latitude in late January 1992.
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As a general rule of thumb, tropical cyclones need to be at least 5 degrees of latitude away from the equator to get enough of a turn in wind direction from the Coriolis force to intensify. Without this turn in wind direction, air would simply converge into the low-pressure center and weaken it, instead of circulating around it.
Incidentally, Typhoon Vamei in late December 2001 formed within 1.5 degrees of the equator near Singapore, the only tropical cyclone of record to form that close to the equator. A 2003 study estimated the probability of a similar event happening again once every 100-400 years.
All known tropical cyclone tracks from 1851 through 2008. Note the gap in tracks near the equator in the center of the map.(NOAA/IBTrACS)
Then there's the oddity of a December or January system in the Pacific Ocean east of the International Date Line.
Dr. Phil Klotzbach, tropical scientist at Colorado State University, said there have been only five December or January named storms (at least tropical storm strength) on record in either the central Pacific (180 to 140 degrees west longitude) or eastern Pacific (east of 140 degrees west longitude).
The last such occurrence was on December 19, 2010, when Tropical Storm Omeka formed well west of Hawaii. One such system, Hurricane Ekeka, formed as late as January 28, 1992, also well south of Hawaii.
Winnie (1983) was the only eastern Pacific named storm to form in December or January. Winona (Jan. 13, 1989) and Paka (Dec. 2, 1997) were the other central Pacific named storms in either of those two months. Paka would later go on to clobber Guam as a super typhoon.
Klotzbach says a record eight named storms formed in the central Pacific basin this season, doubling the previous record of four storms set in 1982.
(MORE: 11 Things We Remember About the 2015 Season)
Tracks of all central and eastern Pacific named tropical cyclones in 2015, prior to the current central Pacific system.A record 15 tropical cyclones either formed in the central Pacific basin, or tracked westward from the eastern Pacific basin in 2015, prior to this current system, topping the previous record of 11 such cyclones set in 1992 and again in 1994, according to the Central Pacific Hurricane Center's season recap.
Record low wind shear, which can inhibit tropical cyclones from forming, as well as record warm sea-surface temperatures from July through October contributed to the record season, according to Klotzbach.
National Hurricane specialist Eric Blake perhaps summed it up best. "A fitting end to a hyperactive year out there!"
MORE: Record-Setting Hurricane Patricia - Oct. 2015
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