MIAMI -- U.S. forecasters say Tropical Storm Sonia is rumbling across the Pacific below the southern tip of Mexico's Baja California peninsula on a projected track toward the mainland.
The U.S. National Hurricane Center in Miami said Sonia grew from a tropical depression early Sunday and is now centered about 250 miles (400 kms) south of the southernmost tip of the peninsula. Maximum sustained winds stand at 40 mph (65 kph) and the storm is moving north at 7 mph (11 kph).
The center says a tropical storm warning extends from Mazatlan northward to Altata on northwest Mexico's mainland. Forecasters expect Sonia to pass south of the Baja peninsula in coming hours and near the mainland coast early Monday.
Forecasters say Sonia could unleash heavy rains and life-threatening flash floods and mudslides.