Published: June 27,2016
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There hasn't been a single named storm of at least tropical storm intensity anywhere in the North Pacific Basin since Hurricane Pali became a January oddball just north of the equator and well southwest of Hawaii.
Most impressive is the lack of a single tropical storm, much less a typhoon (the term for a hurricane in the western North Pacific Basin), west of the international date line since mid-December 2015, in the world's typically busiest tropical cyclone corridor.
Current Satellite Image: Northwest Pacific Ocean
| Start, End Dates | Consecutive Days |
|---|---|
| Dec. 15, 1972 - June 30, 1973 | 198 |
| Dec. 22, 1997 - July 7, 1998 | 198 |
| Dec. 15, 2015 - ?? (through June 27, 2016) | 196 |
| Dec. 11, 1982 - June 24, 1983 | 196 |
The eastern North Pacific basin has already set a record long wait for the first tropical storm in 2016.
June 21, 2009 was the previous record latest date of the eastern Pacific hurricane season's first named storm (Andres). Reliable records in the eastern Pacific basin date to 1971.
Tropical Depression One-E made a failed attempt to become the first of the season in early June. On average, the basin would've seen two named storms, one of which would reach hurricane strength, by late June.
Current Satellite Image: Northeast Pacific Ocean
Fueled in part by a record-tying El Niño, the eastern Pacific Basin saw a record nine hurricanes reach at least Category 3 intensity in 2015, not to mention the strongest tropical cyclone on record in the Western Hemisphere, Hurricane Patricia.
The Central Pacific Basin (from 140 degrees west longitude until the international date line, including Hawaii) also set a record for activity in 2015, with 14 named storms and eight hurricanes, five of which reached at least Category 3 intensity. At one time, three Category 4 hurricanes were active at once in the central and eastern Pacific basins for the first time on record.
(MORE: 11 Things We Remember About the 2015 Hurricane Season)
Thanks in large part to the snoozing north Pacific basin, Klotzbach noted tropical cyclone activity (measured by the accumulated cyclone energy or ACE index) in the northern hemisphere, despite the four named storms so far in the Atlantic basin, set a 45-year record low for the period from January 16 - June 23 in 2016.
N Hemisphere ACE set record (since 1971) high from 1/16-6/23 in 2015, set record low from 1/16-6/23 in 2016.
How Unusual Is This 'Drought?'
This is the first time in records dating to 1950 that the entire North Pacific Basin has failed to generate a single tropical storm from Jan. 15 through June 21, according to Colorado State University tropical scientist Dr. Phil Klotzbach (Note: "Agatha" formed on June 13, 1998, putting an end to the previous record streak).(MORE: You Can Help Improve the Historical Record of Hurricanes)
Despite that, these long dry spells have happened before.
"These types of tropical cyclone droughts are fairly common when moving away from strong El Niño seasons," said Klotzbach via Twitter.
(MORE: How Unusual Are Hawaii Hurricanes?)
As shown in the previous table, Klotzbach noted the four longest such droughts in the western Pacific Basin, including the current event, all immediately followed strong El Niños.
"Both the El Niño and the Madden Julian Oscillation (MJO) have tended to force sinking motion over the Northwest Pacific," said Klotzbach. The MJO is a large-scale, long-period wave of upward and downward motion that propagates around the tropical latitudes.
Why has the NW Pacific been so quiet? One reason... anomalous sinking motion has dominated over past two months.
Typical tropical cyclone activity by month in the western Pacific basin from 1959-2010.As is the case in the eastern Pacific and Atlantic basins, western Pacific activity typically reaches a peak in August and September, so this drought won't last long.
However, with a potential developing La Niña (cooler-than-average equatorial Pacific water; opposite of El Niño) later this summer and fall, Klotzbach also pointed out tropical cyclone activity tends to be less in the Pacific during La Niña years. So perhaps the hard-hit Pacific basin may get a bit of a breather after a frenetic, record-smashing 2015.
Then again, it's important to keep in mind that it only takes one landfall to make any season "active" or "destructive."
(MORE: Are You #HurricaneStrong?)
Jonathan Erdman is a senior meteorologist at weather.com and has been an incurable weather geek since a tornado narrowly missed his childhood home in Wisconsin at age 7.
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