A hurricane watch was issued Sunday for the Florida Keys and Gov. Jeb Bush ordered a state of emergency in anticipation of Tropical Storm Ernesto. Ernesto, which had strengthened into a hurricane for about 10 hours, weakened back into a tropical storm by late afternoon with top sustained winds of 60 mph, the National Hurricane Center said. Still, the Miami-based hurricane center said the storm was expected to strengthen and potentially reclaim its hurricane status before reaching the southeastern coast of Cuba on Monday morning. "It certainly looks like it's going to impact a significant portion of Florida before it's all over," said Max Mayfield, the director of the National Hurricane Center.Officials in the Keys told tourists to postpone any immediate plans to travel there and ordered those already in the island chain to leave. All travel trailers and recreational vehicles were ordered off the islands immediately. Residents were taking notice too: a Home Depot store in Key West was busy Sunday afternoon as customers shopped for generators and other storm-preparation equipment.