The National Weather Service has issued a tornao watch for much of central and south Florida, including Indian River County. The watch will remain in effect until 8 p.m.A band of thunderstorms are approaching from the west coast of Florida in advance of a cold front. The mixture of warm and cold air is causing enough instability for the NWS to issue the warning.The weather service said storm gusts could reach 70 miles per hour, bringing dangerous lightning and possible hail.