It was a nice two weeks of quiet in the tropics, wasn’t it? Unfortunately, that quiet is over. Over the weekend, Hurricane Willa rapidly intensified into a Category 4 beast that’s beelining for the Mexican coast. It will bring fierce winds, powerful surf, and rains that could trigger landslides.
Willa has unfortunately followed the Hurricane Michael playbook. The storm was named on Sunday, and then got to work rapidly intensifying. The textbook definition for rapid intensification is a storm that sees sustained winds increase at least 56km/h over 24 hours, a criteria Willa has met and then some.
Its winds jumped from 64km/h to 161km/h between Sunday and Monday and kept ramping up to 249km/h yesterday. That puts it a hair below Category 5 strength. In an update this morning, the National Hurricane Center (NHC) upgraded Hurricane Willa to a Category 5 storm with winds of 260km/h.
Willa could weaken a bit as it nears land on Friday (Thursday local time), which is a welcome deviation from the Michael playbook. But regardless, the storm will still be formidable. A hurricane warning extends for 282km along the Mexican coast from the city of Mazatlan to San Blas. Tropical storm warnings stretch even further north and south across the Mexican states of Sinaloa and Nayarit.
In addition to powerful winds, the storm will also bring torrential rain. The NHC calls for a wide area of 15-30cm of rain with up to 46cm possible. That could cause flash floods and landslides. The inland desert will also see up to 15cm of rain, but the smaller amounts in a dry landscape could still lead to dangerous flash flooding, too.
“Preparations to protect life and property should be rushed to completion,” the NHC warned.
Willa is the Eastern Pacific’s 23rd named storm of the year. That’s well above the average of roughly 16 for this time of year. Accumulated cyclone energy (ACE), a measure that factors in how powerful and long-lasting storms are, is also pretty bonkers. As of this morning, the ACE value for the Eastern Pacific stood at 302.5, nearly two-and-a-half times higher than normal for this time of year.
A burgeoning El Niño has likely given a boost to the season owing to the warm water and weaker upper level winds in the eastern tropical Pacific. Climate change has also warmed the oceans, another key ingredient for helping hurricanes spin up and sustain themselves. Some research has suggested future warming could make Category 4 and 5 storms more common in the region, though it remains an active area of study.