Eastern Pacific Ocean churns out monster storm after monster storm. Are we headed for a record year?
Monday, September 15, 2014, 10:02 PM -
(EDITOR'S NOTE: This article originally ran on August 27, 2014)
With Hurricane Marie still swirling off the coast of Baja, just days ago the storm became the fifth 'monster' storm of the season, reaching category 4 strength. What's a little unusual about this is, in a season predicted to be 'average to near average', we've already reached the maximum number of major hurricanes predicted, and there's still over three months to go before the season is over!
When the U.S. National Hurricane Center issued its outlook for the eastern Pacific Ocean, just before the May start of the hurricane season, they were figuring on a fairly typical year - 14-20 named storms, and 7-11 hurricanes of which 3-6 would be major hurricanes (Cat. 3+). More importantly, they put the predicted range of storms on the Accumulated Cyclone Energy (ACE) index, which gives a generalized idea of the strength and duration of storms, as opposed to just plotting by numbers and categories, in the 'average' to 'above average' range.
While the signs of a developing El Niño weather pattern in the tropical Pacific Ocean certainly had an influence on this forecast, seeing an actual increase in Eastern Pacific Ocean activity to well above-average would be more likely once the El Niño was actually in effect (ie: next year). So this forecast made sense, and with the Pacific and Atlantic seasons tending to act a bit like a set of scales - with more storms on one side usually meaning less on the other - the corresponding 'average to below average' prediction for the Atlantic made sense as well.
However, it seems that the scales are tipped a bit further than expected this year. The Atlantic season, which was predicted to have between 8-13 named storms, of which 3-6 would be hurricanes and 1-2 of those major hurricanes, is floundering. We're halfway through the season now, and Cristobal, which is barely clinging on to category 1 hurricane status as it moves up the U.S. east coast, is only the third named storm so far. While there's still plenty of potential for the season to 'close the gap' with the forecast, we're about a week away from the season's peak, so it wouldn't be unreasonable to question whether that will actually happen.
Meanwhile, the Eastern Pacific has been turned into a "Freak Hurricane-Producing Machine," as Mashable's senior climate reporter Andrew Freedman aptly put it.
What began as a fairly mixed season, with a combination of hurricanes and tropical storms all the way into mid-July, has turned into a string of hurricane after hurricane since then, culminating in the strongest storm of the season so far: Marie.
When Hurricane Marie peaking as a category 5 storm on Sunday, August 24 - with sustained wind speeds maxing out at 257 kph - it was the 14th named storm of the season, the 9th hurricane, and the 6th hurricane to reach a status of category 3 or higher. Marie is also the first category 5 hurricane to be seen in the Eastern Pacific in over four years (Hurricane Celia, in late June 2010, was the last one).
The pattern this year is in stark contrast to at least the past few seasons (if not even further back), which have seen a fairly good mix of hurricanes and tropical storms throughout the entire season.
Hurricane Marie's majesty and might seen from orbit. Credit: Reid Wiseman, NASA
So, why are things in the Eastern Pacific so active this year, compared to previous years and compared to initial thoughts about what was going to happen this year?
The two maps below, Sea Surface temperatures from NOAA and Sea Surface Temperature anomalies from Environment Canada respectively, show just how warm it currently is in the Eastern Pacific, especially off the coast of Baja California (circled).
Actual SSTs, as of Aug 26, 2014, in degrees C. Credit: NOAA, modified by S. Sutherland
SST's compared to the 1995-2009 average, as of Aug 26, 2014. Credit: Environment Canada, modified by S. Sutherland for easier comparison to above.
That unusually warm patch of ocean off the coast of Baja has been there for months, even over the winter from last year. Apparently, it kept pace as temperatures rose through the spring and summer, but going through a cycle of concentrating, then spreading out along the coast, then concentrating again. In May, this area was a lot more spread out, and wasn't quite so extreme compared to average, so forecasts of an average season were fairly justified. However, since the season started, the anomaly has intensified, providing a nearly uninterrupted fuel source for storms in that region.
By its very nature, weather is chaotic, and there's a long time between now and the end of November for things to develop differently. However, according to National Hurricane Center records, the average number of named storms seen by this time of year is just nine, with five hurricanes and two major hurricanes. We're well beyond that this season, as we'd normally have to wait until October to see number of storms we've had so far.
Even compared to the most active season on record, 1992, we're running fast. In that year, there were a total of 28 named storms, 16 hurricanes, 10 of which were major hurricanes. The strongest storm that year was Hurricane Tina, a category 4 storm that spun up in mid-September. However, by this time of that year, there was less than half those totals - a dozen named storms and seven hurricanes, with four reaching category 3 or higher.
With two more storms behind us in each category, compared to that extreme, record-setting year, if this season continues to show the same performance, this year has the potential to rival 1992, or even surpass it as the year with the greatest number of named storms, hurricanes and major hurricanes.
As for strongest Eastern Pacific hurricane on record, that still belongs to Hurricane Linda, from 1997, which reached sustained wind speeds of 295 kph. However, while sea surface temperatures are higher than normal this year, 1997 saw the development of a 'super' El Niño in the equatorial Pacific (the strongest on record in some ways). With only a weak to moderate El Niño in the works so far for this year (so it seems), it's unlikely that conditions are ripe enough to produce a rival, but only time will truly tell.