Tropical Storm Alvin strengthens off Mexico’s coast in Eastern Pacific

Tropical Storm Alvin formed in the Eastern Pacific south of Mexico on Thursday, becoming the first named storm of the 2025 hurricane season.

A tropical storm has maximum sustained winds between 39 and 73 mph, an upgrade from a tropical depression.

Tropical Storm Alvin is located about 500 miles south-southeast of the southern tip of Mexico’s Baja California Peninsula and is currently being monitored by the National Hurricane Center (NHC) as it continues to churn over the open waters of the Eastern Pacific Ocean.

Tropical Storm Alvin is expected to remain far enough offshore that impacts along the Mexican coast will be limited to heightened swells and increased rip currents along beaches.

These can be a safety hazard for anyone who ventures into the water.

The tropical storm is not only the first of the season in the Eastern Pacific, but across all ocean basins that make up the Northern Hemisphere.

The amount of inactivity is a bit unusual, with forecasters usually tracking the first significant tropical cyclone in the Western Pacific by April, with the first system in the Eastern Pacific by early June.

FOX Weather Hurricane Specialist Bryan Norcross explained that Tropical Storm Alvin formed in the Eastern Pacific when hurricane season would typically get going.

“The Eastern Pacific season kicked off right on schedule. The ocean water off the southern coast of Mexico is always quite warm, and this year the atmospheric pattern over that part of the ocean is quite conducive for development,” Norcross said.

“Alvin has a good chance of intensifying significantly over the open water. As it tracks farther north, however, the water cools quickly. So, if Alvin affects Cabo San Lucas or nearby areas in northern Mexico, for example, it looks likely to be a weakening storm.”

The composition of water temperatures in the Eastern Pacific makes the evolution of Tropical Storm Alvin a bit complex and will impact future tropical cyclones.

There are large pockets of both warmer and cooler water temperatures, meaning that the tropical cyclone’s strength will be determined by its forecast track.

Systems that move over water with temperatures above 78 degrees Fahrenheit are considered to be in an environment warm enough to support the development of tropical cyclones and their continued strengthening.

In contrast, cooler water temperatures make it more difficult for tropical cyclones to develop and intensify.

Mexico’s National Weather Service forecasts that there will be enough warm water this season to support more tropical cyclones than in a typical year, projecting as many as 18 named storms and 10 hurricanes.

Tropical Storm Alvin is expected to reach cooler waters by Friday and quickly fall apart south of Mexico’s Baja California Peninsula.

Once the center of circulation dissolves, forecasters will then watch where the tropical storm’s remnants venture for increased precipitation chances over mainland Mexico and potentially into the southern US.