The National Hurricane Center says Hurricane Norbert has strengthened to a Category 3 storm in the Pacific Ocean.
And the hurricane is forecast to hit Mexico's Baja California peninsula by the weekend.
Norbert's maximum sustained winds have increased to near 115 mph (185 kph) and additional strengthening is expected.
Norbert was centered about 470 miles (755 kilometers) south of the southern tip Baja California as of 5 a.m. EDT Wednesday. The hurricane is moving west-northwest near 10 mph (17 kph).
Norbert's increase in strength comes a day after Tropical Storm Marco slammed in Mexico's Gulf coast before weakening to a tropical depression. The storm hit land about 55 miles (90 kilometers) north of Veracruz.