Hurricane Polo grew into a Category 4 storm in the eastern Pacific late on Monday and was forecast to bring heavy rain to southwestern Mexico but remain offshore.
It had maximum sustained winds of 130 mph (215 kph) and may intensify further, reaching Category 5 strength Tuesday or Wednesday, the U.S. National Hurricane Center in Miami said. Category 4 storms have winds of 130-156 mph (210-250 kph) on the Saffir-Simpson scale, and Category 5 hurricanes have winds exceeding 157 mph (250 kph).
Polo was moving east-southeast at 5 mph (7 kph) and was forecast to sharply turn northwest and west-northwest, which would skirt the Mexican coast for a few days without making landfall.
A tropical storm watch was issued for part of the coast south of Manzanillo in Colima state to Tecpan de Galeana in Guerrero state, meaning tropical storm conditions were possible in the area within two days. Polo was centered about 330 miles (530 kilometers) south-southeast of Manzanillo as of late Monday.
Heavy rain with the potential for flooding and landslides was forecast Guerrero and Michoacán states through Thursday. Smaller amounts of rain were possible in coastal portions of Oaxaca, Colima and Jalisco states.
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