Hurricane Marie was upgraded to a category five hurricane with winds of 160 miles per hour on Sunday.
It’s the first time a hurricane in the eastern Pacific Ocean has reached that intensity since Hurricane Celia in 2010.
Marie will not threaten any land area with winds of even tropical storm strength. However, large waves will impact Baja California and the southern California coast.
In addition, some moisture from Marie could work its way north to enhance the already above-average monsoon rainfall in the American southwest.
The water south of Mexico is normally warm and provides a breeding ground for tropical storms. This year the water temperature is above average, and conditions have been consistently good for tropical cyclone formation.
Marie is the thirteenth named storm, fifth hurricane, and third major hurricane (winds over 135 miles per hour) to be spawned in the area this year. This compares with an average of 16 storms, nine hurricanes, and four major hurricanes. The season has not reached its midpoint, so 2014 is likely to end up above average for all categories of tropical cyclone.
In addition to warm water, the area south of Mexico is characterized by low vertical wind shear (change of wind with height).
The result is a perfect concoction of conditions for the formation of tropical systems. From here they move west and/or northwest into the Pacific Ocean.
The Fate Of Eastern Pacific Hurricanes
Though the hurricane season is typically active in the eastern Pacific Ocean, storms rarely affect land. Hurricanes and typhoons in any parts of the Atlantic or Pacific move west or northwest before curving to the north into higher latitudes.
The waters to the north are too cold to support a hurricane, and to the west, the middle of the tropical Pacific usually has hostile conditions of wind shear and somewhat cooler water. As a result, no eastern Pacific hurricane has traveled all the way across the ocean to impact Asia, though once in a while one reaches the International Date Line and technically becomes a typhoon, as Genevieve did earlier this year.
Only occasionally does an eastern Pacific hurricane turn northeastward quickly enough to affect Mexico. Though it may be disconcerting for Acapulcans to watch so many hurricanes pass within a few hundred miles, they aren’t often impacted by anything but high surf.
Comparison With Atlantic And Western Pacific Tropical Systems
Storms in the Atlantic Ocean and western Pacific Ocean have a clearer path to landfall. In either basin, westward movement often brings the hurricane (Atlantic) or typhoon (Pacific) into position to strike land.
In the Atlantic, westward motion puts the storms onto the coast of Mexico, while northward curving storms reach the Gulf of Mexico or the Atlantic coast of the US. The Caribbean Islands are directly in the path of many Atlantic storms.
In the western Pacific, typhoons can travel westward through the Philippines, as did Super-Typhoons Haiyan last year and Rammasun this year. Northward curving typhoons can affect Japan: Typhoons Neoguri and Matmo reached Japan earlier this year.
Where Will Hurricane Marie Go?
Marie is headed northwest and will continue in that direction until it reaches much colder water and dissipates. Marie is still a major hurricane — category four with winds of 145 miles per hour — but by Wednesday it will be a category one storm (90 miles per hour), and within five days there will be nothing left but a few showers and some gusts of wind to 35 miles per hour.
Will There Be More Eastern Pacific Hurricanes?
Undoubtedly. The conditions that spawned Marie still exist.
In fact, the incubator south of Mexico normally produces storms in every month of the hurricane season (May 15 to Nov. 30). While the points of origin of Atlantic hurricanes change with the season (June 1 to Nov. 30 in the Atlantic), the points of origin are the same in every month in the eastern Pacific — south of Mexico.
So expect more action in the eastern tropical Pacific in the weeks to come. And as the jet stream moves south with the onset of fall, the probability that an eastern Pacific hurricane will be steered into the Mexican coast is a little higher.