Hurricane Sam continued to strengthen Friday afternoon, and is forecast to become a Category 4 storm over the weekend, according to the National Hurricane Center. In less than 24 hours, the system intensified from a tropical depression into a hurricane, and it isn’t expected to slow down any time soon. Sam's path is a little unpredictable, though high pressure and currents could steer the storm north and north-west. AccuWeather forecasters say there is a range of possibilities as to where Sam might go, and is urging residents along the East Coast to monitor the system for potential impact. Sam's winds are expected to reach 130 miles per hour by Sunday morning. A major hurricane is one with winds of at least 111 miles per hour.