Aletta (2018)

A tropical depression formed from a westward-moving tropical wave that developed a well-defined center at 0000 UTC on 6 June 2018 about 300 nautical miles south‑southwest of Manzanillo, Mexico. It strengthened to a tropical storm later that morning and moved generally west to west‑northwest, well offshore of Mexico. Between 7 and 9 June the storm moved over very warm water and under favorable conditions, then weakened rapidly as it moved into cooler, more stable air and became a remnant low by 1200 UTC 11 June. The remnant low lingered and dissipated several days later.

Aletta remained far from the Mexican coast and did not make any landfalls. The closest approach to land was about 120 nautical miles south of the Mexican Navy station on Isla Clarión, Colima, which recorded sustained winds of 35 kt and a peak gust of 47 kt around 1715 UTC on 10 June. No watches or warnings were required for coastal areas.

The hurricane reached a maximum intensity of 120 kt (approximately 138 mph) with a minimum central pressure of 943 mb at 1200 UTC on 8 June, making it a Category 4 hurricane at peak. The peak intensity followed a period of rapid intensification in which the winds increased by about 65 kt in 24 hours.

Storm surge and rainfall impacts were minimal along Mexican coasts because Aletta stayed well offshore. The closest marine weather station of note, at Isla Clarión, measured the winds noted above; there were no significant storm surge reports or major rainfall totals tied to the cyclone in populated Mexican cities or counties in the official record.

There were no reports of damage or casualties—no direct or indirect deaths—associated with Aletta. It was the first Category 4 hurricane of the 2018 eastern North Pacific season and notable for its rapid intensification to that peak followed by an unusually swift weakening from Category 4 to a tropical storm in about 30 hours. Forecasts anticipated formation several days in advance, but official intensity forecasts underpredicted the storm’s peak strength.