Hurricane Alex, the Atlantic Basin’s strongest June hurricane in 44 years, has been downgraded to a tropical storm as it moves over mountainous terrain, after “ripping off roofs, causing severe flooding and forcing thousands of people to flee coastal fishing villages” in northern Mexico.
Meanwhile, Dr. Jeff Masters is looking back at some eyewall replacement weirdness that happened yesterday as Alex was winding up and nearing the coast:
Alex had several rather remarkable features I’ve never seen in a hurricane. Firstly, it underwent an eyewall replacement cycle as a Category 1 hurricane with 80 mph winds. Usually, we don’t see the inner eyewall collapse and an eyewall replacement cycle occur until a hurricane reaches Category 3 strength. I’ve seen it happen on occasion to a Category 2 storm, but never a Category 1. Secondly, after Alex’s inner 9-mile diameter eyewall collapsed at 10am EDT yesterday morning, an outer spiral band began to become the new eyewall. Winds in this outer spiral band/new eywall increased as the day progressed, as typically happens in an eyewall replacement cycle. However, part way through that process, Alex suddenly reversed course, and was able to build a small inner eyewall with a 12-mile diameter that was completed by landfall. I’ve never seen a hurricane change its mind in the middle of an eyewall replacement cycle and build an inner eyewall so fast.
Interesting. Here’s a NASA image of Alex as of midday yesterday:
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