Stalled Storm System Expected to Swamp, Steam Northern Gulf Coast

State officials urged residents and businesses Sunday to prepare for heavy rain leading to widespread flash floods this week along the entire width of the Florida Panhandle.

A low-pressure system was stalled over the northern Florida peninsula, fueling a chance of heavy showers and thunderstorms that the National Weather Service put at 80 percent to 90 percent across the northern Gulf Coast.

"We have the potential, because this is going to stay problematic for the next few days, of dealing with 8 to 12 inches of rain — up to a foot of rain," said Danielle Banks, a meteorologist for The Weather Channel.

IMAGE: Florida flooding
Heavy rain causes flooding Sunday on Cedar Key Island off the Florida Gulf Coast. NBC News Channel

Combined with high afternoon temperatures in the lower to mid 90s, the system is forecast to create inordinately steamy conditions, with heat indexes predicted to hit 102 to 107 degrees all the way across the state from Pensacola to Jacksonville, forecasters said.

Flood watches were in effect Sunday night for the Florida Nature Coast and Big Bend all the way into Tuesday. Parts of western North Carolina, upstate South Carolina and far northeast Georgia were under flash flood watches into Monday.

"We're urging everyone along the Gulf Coast to prepare for increased flooding potential as rainfall totals accumulate throughout the week," said Bryan Koon, director of the Florida Division of Emergency Management.

Why We Should Pay More Attention to Flood-Proofing America 1:09

Laurie Kennedy of Hillsborough County was already filling sandbags Sunday in anticipation of the rough week ahead.

"There's been flooding in the past over at my dad's place, and we don't have flood insurance," Kennedy said. "And it's really too expensive. So he's just very nervous about it."