In the United States, Hurricane Irma surged to a dangerous Category Four storm today as it churned toward the Leeward islands, sparking alarm and alerts from the Caribbean to Florida. <br/><br/>The National Hurricane Center said that the storm was packing top sustained winds of 215 kilometre per hour. Additional strengthening is forecast during the next 48 hours. On the forecast track, the center of Irma will move near or over portions of the northern Leeward Islands tonight and early tomorrow.