Havana.– Hurricane Gustav, now a major storm picking up steam over warm sea waters, roared toward western Cuba on Saturday en route to the oil-rich Gulf of Mexico after a deadly pass through the Caribbean.

Gustav ripped across the Cayman Islands and took aim at Cuba's Isle of Youth before it was set to strike the Cuban mainland later in the day.

Forecasters predicted Gustav would cross the Gulf of Mexico and hit central Louisiana on Tuesday with the same brutal force Hurricane Katrina delivered three years ago.

The U.S. National Hurricane Center said Gustav's sustained winds had risen to 120 mph (195 kph), making it a dangerous Category 3 storm on the five-stage Saffir-Simpson scale of hurricane intensity.

Any storm with winds of at least 111 mph (178 kph) is ranked "major" by the Miami-based hurricane center.

Forecasters said Gustav could grow to a Category 4, with winds of at least 131 mph (210 kph), before reaching the Cuban coast, and may strengthen further on Sunday when it goes into the Gulf of Mexico, where offshore platforms produce 25 percent of U.S. oil and 15 percent of its natural gas.

Gustav was expected to dump up to 12 inches of rain as it crossed Cuba on its way to the gulf.

The storm's center was 85 miles southeast of the Isle of Youth and 225 miles from Cuba's western tip, forecasters said Saturday morning. It was moving north-northwest at 12 mph (19 kph).