Why are so many hurricanes heading towards the U.S. in 2017?
The Atlantic Ocean is primed for making major hurricanes right now due to three major ingredients.
The mainland of the USA usually has a ridge of low pressure along it’s east coast, which helps steer storms away. But this invisible ridge has pushed west this year, leaving the eastern seaboard, the Caribbean and the Gulf of Mexico exposed to hurricanes.
The other two ingredients are warm Atlantic Ocean temperatures that extend deep underwater, creating high levels of moisture in the air as it evaporates.
Irma grew in power thanks to sea temperatures hovering around 85 degrees Fahrenheit, which are ideal for fueling hurricane intensification. Irma followed on the heels of Harvey, which began on the 17th of August, because of this change in air pressure along the East Coast. These ripe conditions allowed Hurricane Irma, that hit the USA on the 30th of August and later Hurricane Jose, which affected the mainland starting on September 5th to form and be destructive.
And 160 miles per hour hurricane Maria followed suit on the 18th of September, utterly leveling the Caribbean island of Dominica and causing “mind boggling” levels of destruction, according to its prime minister Roosevelt Skerrit.
Why didn’t the experts see these huge storms coming?
Some did, including Philip Klotzbach, an atmospheric scientist at Colorado State University.
In early July, Klotzbach’s team predicted the Atlantic Ocean would experience an above-average hurricane season because of the El Niño-Southern Oscillation (ENSO) – or rather because of its absence this year. “We’ve only had 16 other hurricanes on record that have been as strong as Irma is right now,” he told reporters at the time of the hurricane.
The El Niño weather phenomenon creates extremely warm temperatures in the Pacific Ocean, which pushes strong winds into the Atlantic, creates high levels of wind shear and stops hurricanes. When Pacific sea temperatures reverse and cool, it creates La Niña, which tends to drive hurricanes.
Gusts from Hurricane Irma topped 220mph.
Why do hurricanes never hit the West Coast of the U.S.?
Hurricanes form both in the Atlantic basin, to the east of the continental US and in the Northeast Pacific basin, to the west of the US.
The hurricanes in the Northeast Pacific almost never hit the US, however, whereas the ones in the Atlantic basin strike the US mainland just less than twice a year on average. There are two main reasons for this disparity.
The first is that hurricanes in the northern hemisphere form at tropical and subtropical latitudes and then tend to move toward the west-northwest. In the Atlantic, such a motion often brings the hurricane into the vicinity of the East Coast of the U.S.
In the Northeast Pacific, the same west-northwest track carries hurricanes farther offshore, well away from the US West Coast. The second factor is the difference in water temperatures along the US East and West coasts. Along the East Coast, the Gulf Stream provides a source of warm (above 80 degrees Fahrenheit, or 26.5 degrees Celsius) waters, which helps to maintain the hurricane. Along the West Coast, however, ocean-surface temperatures rarely rise above the lower 70s F (the low 20s C.) even in the middle of summer. Such relatively cool temperatures do not provide enough thermal energy to sustain a hurricane’s strength. So the occasional Northeast Pacific hurricane that does track back toward the US encounters the cooler waters of the Pacific, which can quickly reduce the storm’s strength.”
ServiceMark Heating Cooling & Plumbing makes it a point to not only track and be aware of adverse weather conditions that cause problems for our customers and their homes, but to also closely watch the big destructive storms, so that our team is ready and prepared to provide assistance during these tough times!
Many thanks go out to the reporters, at the the Sun, a United Kingdom publication, who helped in the creation of this blog.