The storm's effects were being felt in South Florida, in the Keys and across the state, with 1 to 3 inches of more rain expected Monday, forecasters said, in areas already saturated from an above-normal rainfall in May.
Coastal areas could also experience 2 to 4 feet of storm surge.
Thousands of Florida residents evacuated homes on Sunday as the storm headed north through the Gulf of Mexico.
TORNADOES: A couple of brief tornadoes are possible today from northern Florida into central and southern Georgia, southern SC, and southeastern Alabama.
A flash flood watch has been extended until Wednesday morning for parts of Central Georgia. "It's still way too early to forecast the amount of rainfall this system will produce for the local area, but (we) will continue to monitor". Very little change in intensity or forward motion is expected by the time it makes landfall. At the moment nearly all of the showers are on the east of Alberto's centre, with the heaviest rains falling across Cuba and Florida.
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The dentist, from India, was 17 weeks pregnant when she presented to University Hospital Galway with severe back pain. Members of the public hold "no" placards as the country heads to the polls, May 25, 2018 in Dublin, Ireland .
Alberto got an early jump on the 2018 hurricane season, which doesn't officially start until Friday.
Gusty showers were to begin lashing parts of Florida on Sunday, and authorities were warning of the possibility of flash flooding. The storm, coming on the last day of the Memorial Day weekend, was expected to scramble holiday travel on Monday.
"We're going to play cards and if there's a break, we'll head down to the beach", she said.
It's also worth pointing out that extremely heavy rain continues to fall over Cuba from a trailing moisture plume ... this is the fifth consecutive day.
The National Oceanic and Atmospheric Administration released a hurricane season forecast Thursday that calls for 10 to 16 named storms, with five to nine hurricanes.
Maximum sustained winds are near 50 miles per hour with higher gusts.
Moore said the rainy weather late this month is expected to push the Columbia area past its average precipitation for May, typically one of the state's driest months.