Hurricane Irma gained strength Monday as experts warned of “life-threatening conditions” once the Category 3 storm hits the islands of the east Caribbean late Tuesday. The National Hurricane Center said Irma was about 610 miles east of the Leeward Islands as of Monday morning, with winds at 120 mph, CNN reports.The storm will remain a “dangerous major hurricane” throughout the week and may affect Puerto Rico, the British and U.S. Virgin Islands, and the Bahamas, the agency said. It’s still unclear if the storm will hit the U.S. East Coast, but Florida Gov. Rick Scott urged residents to “be prepared” on Sunday. Officials for the American Red Cross told North Carolina’s WNCN-TV the agency’s resources might be diverted from Texas in anticipation of Hurricane Irma. “We put a hold on sending volunteers from the Mid-Atlantic states,” Regional Executive Officer Barry Porter was cited as saying, adding that volunteers had been asked to be ready to head to Florida, Georgia, South and North Carolina if Irma hits.