The U.S. National Hurricane Center says Paul's maximum sustained winds were 80 mph (130 kph) early Monday. Some additional strengthening is forecast during the day before weakening is expected Tuesday.
It's centered about 530 miles (850 kilometers) southwest of the tip of the Baja California peninsula and moving north at 9 mph (15 kph).
Meanwhile, Tropical Storm Rafael is expected to reach hurricane strength in the Atlantic later in the day.
Rafael's maximum sustained winds are near 70 mph (110 kph). The storm is centered about 290 miles (465 kilometers) north of San Juan, Puerto Rico, and is moving north-northwest near 10 mph (17 kph).