(This report was updated at 11 a.m. Friday based on new information about its intensity from the National Hurricane Center.)
The 2018 Eastern Pacific hurricane season has begun with a blast.
Aletta, the first named storm of the season, rapidly intensified Thursday night, becoming not only a hurricane but also a powerhouse Category 4 Friday morning.
The storm, which is no threat to any land area, is packing maximum sustained winds of 140 mph. Its winds increased 65 mph in 18 hours, between 5 p.m. Thursday, when it was first named a hurricane, and 11 a.m. Friday, when its rating shot up to Category 4.
“The remarkable intensification of Aletta has continued through this morning,” the National Hurricane Center wrote in its 11 a.m. advisory.
Aletta is about 500 miles west of Mexico’s west coast and is moving even farther away from land over the Pacific Ocean. It boasts a beautiful presence on satellite imagery, almost perfectly symmetric and featuring a well-defined eye.
Churning over warm waters that can provide fuel and with relatively little wind shear to disrupt its towering thunderstorms, “there are no obvious reasons why Aletta should cease intensification,” the National Hurricane Center said. It predicts the storm’s intensity to peak late Friday, with maximum winds of 145 mph, about 10 mph shy of Category 5 levels.
However, over the weekend, the storm is forecast to steadily decay.
“The hurricane has less than a day to strengthen before the environment becomes less hospitable, with a notable increase in shear and decrease in water temperatures forecast this weekend,” the National Hurricane Center said. “These conditions will likely cause significant weakening of Aletta over the weekend, with rapid weakening predicted by Sunday.”
Aletta was first named a hurricane on Thursday, June 7, which is more than two weeks earlier than normal. The first eastern Pacific hurricane forms on June 26 on average.
While it may seem strange for the Pacific’s first storm to be so strong, Weather.com meteorologist Jonathan Erdman discovered it’s not all that uncommon. “It’s happened 3 other times this decade, and a total of 9 times since 1970, per NOAA’s database,” he tweeted.
To the southeast of Aletta, another area of disturbed weather is forecast to become a tropical depression or storm in the next 48 hours. If the disturbance earns a name, it will be called Bud. Computer models suggest moisture from this system could get drawn up into the Desert Southwest late next week feeding afternoon showers and storms.