Mexico City : Two tropical storms were gaining force and pushing westward across the Pacific on Monday, at least one of them on a path likely to take it just south of the Hawaiian Islands at week's end.

The US National Hurricane Center said Tropical Storm Erick was about 2,375-kilometres east-southeast of Hilo, Hawaii, early Monday. It had maximum sustained winds of 110km/h and was moving toward the west at 26km/h.

The center said Erick could grow into a major hurricane Tuesday but was expected to begin losing strength Wednesday and gradually weaken into a tropical storm before nearing Hawaii.

Father to the east, Tropical Storm Flossie formed, and it was following a roughly similar track, though a bit to the north.

It was centered about 745 miles (1,200 kilometers) south-southwest of the southern tip of the Baja California Peninsula and was moving west at 20 mph (31 kph). The storm had maximum sustained winds of 40 mph (65 kph), though it too was projected to grow into a hurricane on Tuesday or Tuesday night.