Alberto is forecast to continue a north-northeastward path on Saturday, then turn northwestward on Sunday and Monday, making a landfall on the northern Gulf Coast on Monday evening.
Several counties along the coast remain under a tropical storm warning, including Pinellas, Hillsborough, Pasco and Hernando.
A tropical storm warning has been issued for the Mississippi/Alabama border to the Aucilla River in Florida.
As Alberto moves northward it's expected to carry plentiful rainfall with it. Forecasters said maximum amounts up to 15 inches are possible along its track between eastern Louisiana, Mississippi, Alabama and the western Florida. "Today, I have declared a state of emergency in all 67 Florida counties to make sure that our state and local governments are able to coordinate with federal partners to get the resources they need", Scott said. There's always a low-end risk of severe storms or a quick spin-up tornado on the left (eastern) side of tropical systems, which will be the case for eastern Alabama.
Parts of the Alabama and Florida coast were placed under a tropical storm warning Saturday afternoon with MS still under a watch.
The track for Alberto shows it aiming for the Florida Panhandle on Monday.
A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area. Expect rounds of heavy rain through Tuesday with widespread rain totals of 2 to 3 inches expected with locally higher amounts possible.
Earliest reasonable arrival time of tropical storm
Heavy rainfall is expected for Memorial Day Weekend in South Florida, as Subtropical Storm Alberto has formed over the Caribbean Sea.
Maximum sustained winds are near 40 miles per hour with higher gusts.
Stormchaser Jim Cantore said in a social media post, "a plethora of hazards will ramp up Sunday for U.S. and be with us through Tuesday".
Some experts have said subtropical storm Alberto is not a true tropical system yet but warned it may get stronger over the coming days.
The story changes for Monday, however, when North Carolina will begin to feel the tropical moisture pushed up from the Gulf of Mexico by Subtropical Storm Alberto.
Storm Surge: The combination of storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline. Isolated tornadoes were also possible.More news: Mike Pompeo Promises 'Strongest Sanctions In History' On Iran