Tag Archives: ENSO

HURRICANE SEASON 2018: THE ATLANTIC WAKES UP!

Earlier this year predictions called for a rather active 2018 Atlantic Hurricane season, but as an incipient ENSO began to show off the Pacific coast of Peru and Ecuador and other contributing factors became evasive, predictions were changed to a “somewhat below average” to “average” season, whatever “average” means.

The reality of tropical cyclone activity in 2018 in the Earth’s northern hemisphere is that while the Northwest Pacific has already seen 23 named-storms, some of them ferocious category 5 cyclones, and the East Pacific is already up to 15 named-storm, the Atlantic basin has been somewhat quiet with  barely six named-storm by early September until FLORENCE, number 7, appeared over the eastern Atlantic but soon encountered an adverse ocean-atmosphere environment and wind shear, which weakened considerably putting in doubt its future progress.

Full Disk – Clean Longwave Window – IR

As of today all of that has changed, FLORENCE is regaining strength and may possibly become a major hurricane as it continues to move toward the Carolinas on the east coast, while two other tropical storms HELENE and ISAAC have formed over the far eastern Atlantic. At the same time, a low pressure system moves over Bermuda ahead of Florence, and a menacing looking tropical wave over equatorial Africa continues moving westward toward the Atlantic just south of the Cape Verde islands, and a large cell of disturbed weather is on the march in the Caribbean. So, as of this Saturday 8 September we have reached nine named-storm and there is plenty of fuel for additional cyclonic activity in the Atlantic basin.

Projected track of FLORENCE as of 8 September 2018

All interests in and around the north Atlantic basin must monitor these named tropical cyclones closely over the next few days, and be on the alert for other potential cyclonic activity in days to come. Be prepared! MITIGATE!

Projected Hurricane OLIVIA as of 8 September 2018 has it aiming for Hawaii

Elsewhere, hurricane OLIVIA appears to be aiming for Hawaii, which is still recovering from the brush with LANE just a couple of weeks ago. Farther to the west, Typhoon MANGKHUT is moving over the northwest Pacific in the general direction of the northern Philippines, Taiwan, and Japan. This is a region that has already seen several landfalling tropical cyclones causing plenty of damage and human suffering.

Subdued 2016 Tropical Cyclone Activity so far in the Northern Hemisphere

A bit more than two weeks into the 2016 Northern Hemisphere summer we have three-named storms active over the larger Pacific Ocean basin, plus one tropical wave moving westward in the middle of hurricane alley in the Atlantic.

A tropical wave moves westward toward the Caribbean along 'hurricane alley'. Satellite images from NOAA on 07072016 using infrared filter
A tropical wave moves westward toward the Caribbean along ‘hurricane alley’. Satellite images from NOAA on 07072016 using infrared filter

Hurricane BLAS and AGATHA, now a tropical depression, are moving westward some 2000 kilometers east of the Big Island in Hawaii, while category 5 typhoon NEPARTAK, now weakening somewhat, is approaching landfall on the east coast of Taiwan over in the West Pacific on this Thursday 7 July 2016.

NOAA GOES satellite image of 07072016 showing Hurricane BLAS moving over the eastern Pacific approximately 2000 kilometers east of Hawaii
NOAA GOES satellite image of 07072016 showing Hurricane BLAS moving over the eastern Pacific approximately 2000 kilometers east of Hawaii

Tropical cyclone activity so far in 2016 in the northern hemisphere has been somewhat subdued in terms of actual cyclogenesis when compared to recent years.  As of today, Thursday 7 July 2016,  there have been 11 named tropical cyclones worldwide in the northern hemisphere compared to 19 during the same period in 2015. Three of the 2016 storms have only been generated over the past couple of days. The only basin that is a bit more active so far in 2016 versus 2015 is the northern Atlantic, which actually saw its first name tropical cyclone,  Alex, in January of this year, which ended up winding over the central North Atlantic and eventually impacting Greenland.

Satellite image [NOAA} of 07072016 showing Typhoon NEPARTAK approaching landfall on the east coast of Taiwan
Satellite image [NOAA} of 07072016 showing Typhoon NEPARTAK approaching landfall on the east coast of Taiwan
In my opinion, most of this change in tropical cyclone activity so far in 2016 may be attributed to the current neutral El Niño  conditions over the central to eastern Pacific near the equator, after a strong ENSO (El Niño Southern Oscillation) anomaly in 2015 and earlier this year.  Sea-surface temperatures (SST) at the equator are somewhat cooler than average in the central-to-eastern Pacific Ocean. Conditions are looking favorable for the development of La Niña during this 2016 summer in the Northern Hemisphere, perhaps by the fall and the 2016-2017 winter.

There were a total of sixty-six named tropical cyclones plus eleven tropical depressions in the Northern Hemisphere during 2015. Only time will tell how many named storms we will have in 2016, and which basin will see above or below average seasons this year.

Historically La Niña years have brought increased cyclogenesis over the northern Atlantic basin, and the forecast from the National Hurricane Center and others that have issued predictions calls for a somewhat above average 2016 Atlantic Hurricane season.

All interest in and around the Atlantic basin should pay attention,  remain alert, be prepared, and mitigate!