A new tropical storm has formed in the Pacific Ocean, potentially bringing dangerous winds, rain and flooding as it moves along the West Coast.
The 13th storm of the Pacific hurricane season has been named Mario, and on Friday the National Hurricane Center (NHC) called it a “mini” tropical storm.
Mario formed about 23 miles off the coast of Guerrero, Mexico, with sustained winds near 40 mph after rapidly strengthening overnight.
The storm is moving west-northwest at about 14 mph, roughly parallel to the southwestern coast of Mexico.
It is expected to continue on this track for several days under the influence of a high pressure ridge over northern Mexico and the Pacific Ocean.
A tropical storm watch was in effect for parts of Michoacan state, extending from Lazaro Cardenas to Punta San Telmo.
Forecasters warned that Mario is expected to strengthen as it moves north closer to the southwestern United States, with Accuweather experts adding that the storm could turn into a hurricane before reaching the Baja California peninsula.
Heather Zehr, senior meteorologist at Accuweather, said: “Some moisture could start to appear in the form of clouds and spotty showers as early as Tuesday, centered over parts of southern California, Arizona and southern Nevada, but that’s likely to be from Wednesday.”
This is a developing story. More updates to follow.
Tropical Storm Mario formed Friday morning off the southern coast of Mexico

Mario is moving up the west coast of Mexico and while it is
Mario is expected to continue moving west-northwestward for at least the next four days under the influence of a mid-level ridge over northern Mexico and the eastern Pacific Ocean.
“Mario will bring rainfall totals of 2 to 4 inches, with a local total of 6 inches, across southern Mexico through Sunday,” the NHC alert read.
“This poses a risk of flash flooding, especially in areas of higher terrain.”
While Mario is currently off the coast of Mexico, meteorologists are monitoring the sudden shift towards the United States.
ABC meteorologist Jorge Torres shared with X, “It’s still too early to know if this could affect Arizona or the desert southwest… but we’re watching closely.”