Plunging temperatures across Florida have citrus farmers worried about their crop. By early Thursday morning temperatures across central portions of Florida will likely drop into the middle to upper 20s for a few hours. To do significant damage temperatures have to stay below freezing for six hours or longer. Florida produces much of our country's domestically grown fruits and vegetable during the winter months. Freeze warnings have been posted for areas including Tampa and Orlando northward into the Florida Panhandle for Thursday morning.