MEXICO CITY -- Hurricane Bud strengthened in the Pacific Ocean west of Mexico on Sunday even as former Hurricane Aletta was fading. Neither immediately threatened land, though Bud was expected to kick up high surf along the Mexican coast and potentially could reach the Los Cabos resort region by Thursday or Friday.

said Bud had maximum sustained winds of 80 mph (130 kph) Sunday evening. It was centred about 235 miles (380 kilometres) south of Manzanillo, Mexico, and was moving northwest at 9 mph (15 kph).

Forecasters said Bud likely would strengthen rapidly for a day or so, but then begin to weaken late Tuesday or early Wednesday.

The Hurricane Center said the storm could generate swells that cause life-threatening surf and rip currents over the coming days along Mexico's southwestern coast.

Meanwhile, Tropical Storm Aletta's winds were down to 45 mph (75 kph). It peaked on Friday as a Category 4 hurricane with winds of 140 mph (220 kph). It was about 575 miles (925 kilometres) southwest of the southern tip of the Baja California Peninsula.