Ciudad Obregon, Mexico - Hurricane Norbert strengthened Wednesday into an extremely powerful Category 4 storm off Mexico's Pacific coast and was on track to hit the southern Baja California peninsula over the weekend.

The U.S. National Hurricane Center said Norbert will likely turn toward the northeast over the next two days en route to the Baja peninsula and Mexican mainland. Officials across the region were setting up shelters and preparing for possible evacuations from low-lying regions.

In Ciudad Obregon, across the Sea of Cortez from Baja California, farmers were rushing to finish fertilizing their fields before the hurricane hit. At the Fiesta Inn hotel, workers were sealing wood decks to prepare for the heavy rains.

The storm had maximum sustained winds near 135 mph and was moving west-northwest at near 9 mph late Wednesday, the hurricane center said. It was expected to reach a relatively unpopulated stretch of coast well north of Cabo San Lucas before dawn Saturday.

Norbert was centered about 420 miles south of the southern tip Baja California on Wednesday night.

Baja residents were waiting to see what the storm would do before preparing.

"Everything is very calm right now. Only a sporadic shower or two," said Elizabeth Guillien, manager of Hotel Conquistador in Ciudad Constitucion, a town in the southern peninsula.

Norbert is the seventh hurricane of the east Pacific season.

Further south, a tropical depression formed Wednesday off Central America's Pacific coast, near the El Salvador-Nicaragua border. Maximum sustained winds were near 35 mph.

The depression was dumping rain across Central America as it headed toward Mexico's southern coastline. Forecasters warned it could cause mudslides.

And in Mexico's Gulf coast, Tropical Storm Marco was a rain shower Wednesday after slamming into land with near hurricane-force winds and leaving flooding in its wake.