AlQa'dah 29, 1433, Oct 15, 2012, SPA -- Tropical Storm Rafael swirled in the central Atlantic Ocean early Monday as it neared hurricane strength, U.S. forecasters said. Maximum sustained winds increased to 113 kilometers per hour (kph) late Sunday, according to the National Hurricane Center in Miami. On Monday, the storm was centered about 465 kilometers north-northwest of the Caribbean island of Puerto Rico and was moving north-northwest at 16 kph. “Some strengthening is forecast, ... and Rafael is expected to become a hurricane later today," the NHC said. A projection map showed Rafael headed toward Bermuda later this week. Officials in the wealthy British territory issued a tropical-storm watch Sunday and told residents they expected the storm to affect the island on Tuesday. While the NHC predicted Rafael will stay far to the east of the Bahamas through Monday night, it did warn of life-threatening surf conditions on the eastward-facing beaches of the Bahamas over the next few days. Forecasters expect Rafael to drop between 10 and 20 centimeters of rain over the northern Caribbean islands, with some areas getting as much as 25 centimeters. “These rains could cause life-threatening flash floods and mudslides, especially in areas of mountainous terrain, the NHC said.