NAVARRE BEACH, Florida (AP) — Heavy rain and pounding surf driven by Hurricane Sally hit the Florida and Alabama coasts today as forecasters expected the slow-moving storm to dump continuous deluges before and after landfall, possibly triggering dangerous, historic flooding along the northern Gulf Coast.

“It’s going to be a huge rainmaker,” said Phil Klotzbach, a research scientist and meteorologist at Colorado State University. “It’s not going to be pretty.”

The National Hurricane Center expected Sally to remain a Category 1 hurricane, with top sustained winds of 80 mph (130 kph) at landfall late Tuesday or early Wednesday. The storm’s sluggish pace made it harder to predict exactly where its centre will strike.

The hurricane’s slow movement exacerbated the threat of heavy rain and storm surge. Sally remained dangerous even after losing power, its fiercest winds having dropped considerably from a peak of 100 mph (161 kph) on Monday.

Tuesday evening, hurricane warnings stretched from east of Bay St Louis, Mississippi, to Navarre, Florida. Rainfall of up to 20 inches (50 centimetres) was forecast near the coast. There was a chance the storm could also spawn tornadoes and dump isolated rain accumulations of 30 inches (76 centimetres).