Another tropical storm has formed in the Pacific Ocean and is bearing down on Mexico.

Tropical Storm Sonia had formed about 285 miles south of the Baja California peninsula. The storm has maximum sustained winds of 40 m.p.h. and is moving north at 7 m.p.h.

The National Hurricane Center said that a tropical storm warning has been issued from Mazatlan north along Mexico’s mainland. The forecasters expect Sonia to pass south of Baja California before making landfall somewhere on the Mexican mainland.

Heavy rain could hit a wide area and local officials are warning residents about possible mudslides and flash flooding.