PUERTO VALLARTA, Mexico (AP) — Simon has strengthened into a powerful Category 4 hurricane as it barrels toward Mexico’s coast.

The National Hurricane Center in Miami said Saturday that Simon’s maximum sustained winds increased to 150 mph (240 kph). A storm of that strength or greater is considered a major hurricane.

The center said it expected Simon “to be near or just inland” of Mexico's west-central coast on Sunday. The hurricane could bring as much as 10 to 20 inches (25-50 cm) of rain over parts of southwestern Mexico, with some areas in the states of Michoacan, Colima and Jalisco receiving up to 30 inches (76 centimeters) .

“This rainfall will produce life-threatening flooding and mudslides, especially in areas of steep terrain,” the center warned in a bulletin that also urged residents to take immediate action to prepare as tropical-storm conditions were expected to arrive Saturday afternoon.

Jalisco state suspended classes on Friday and Monday in 22 coastal municipalities and began evacuating dozens of people from at-risk areas. It also asked the tourism sector in Puerto Vallarta, a popular destination for U.S. tourists, to ensure that both workers and visitors were fully accommodated in shelters or safe zones by Friday afternoon.

Convenience stores, hotels and other businesses in Puerto Vallarta were boarding up their windows Saturday morning, when few were walking the streets under overcast skies.

The hurricane center expected a dangerous storm surge “along the immediate coast near and to the east of where the center makes landfall.” The agency warned that near the coast, large and destructive waves will accompany the surge.