Tropical Storm Rafael, which produced heavy rains and strong winds in the Virgin Islands, is now threatening Bermuda, forecasters say. A tropical storm watch for Rafael was issued for Bermuda on Saturday, the National Hurricane Center said. Tropical Storm Rafael is moving north-northwest at about 12 mph and is expected to move toward the north Monday. The storm has produced gusts of up to 60 mph and four to six inches of rain in the Virgin Islands. At 8 a.m. AST, the storm was about 100 miles north northwest of St. Martin, moving north northwest at 12 mph, the National Hurricane Center reported. \"Some strengthening is forecast during the next 48 hours and Rafael could become a hurricane by Monday,\" the center said. \"Interests in Bermuda should monitor the progress of Rafael.\" Tropical-storm force winds were extending up to 175 miles to the northeast and east of the storm center, data from buoys indicated. The U.S. Coast Guard and U.S. Virgin Islands Department of Natural Resources were battling the conditions to search for three people who were aboard a small aircraft that crashed Saturday about seven miles south of St. Thomas, CNN said. The twin-engine plane took off from St. Croix and was bound for St. Thomas. One woman was rescued soon after the crash, but she said there two other men and a woman aboard the plane. Another storm -- Tropical Storm Paul -- has been located over the water, west of Baja California, the National Hurricane Center said. That storm has prompted no watches or warnings and is expected to weaken by Monday evening.