Subtropical storm Alberto, slowly strengthening as it draws closer to the Gulf Coast, set off new tropical storm warnings stretching just north of Naples up past the tip of Florida's Panhandle on Sunday night.
Forecasters said Alberto was moving northwest near the eastern Gulf of Mexico at 10 mph and that the storm would approach the northern Gulf Coast by Sunday night or Monday. The storm is forecast to become a tropical depression by Monday night or Tuesday.
In the 11 p.m. advisory, the National Hurricane Center said the storm's maximum sustained winds remained 65 miles per hour with higher gusts, much faster than the 45 mph winds recorded at earlier Sunday. Alberto is currently located about 205 miles west of Tampa.
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In the earlier advisory, forecasters discontinued the tropical storm warning along the west coast of Florida, south of the Anclote River. A storm surge watch was also discontinued along the northern Gulf Coast, west of Navarre. Still in effect is the tropical storm warning north of that point and up to the Mississippi-Alabama border.
But residents in the northern Gulf Coast will feel Alberto before they see the storm, forecasters say, adding that heavy rainfall and tropical storm conditions will likely reach the region by Sunday night. Those conditions will be felt along the warning zones on the west coast of Florida as well, according to the National Hurricane Center.
In the Florida Keys and the rest of South Florida, Alberto is expected to drop an additional three to six inches, with isolated storm totals of 10 inches, on Sunday, the hurricane center said. Forecasters warn that the storm could bring heavy rain and a risk of flooding and flash flooding to western Cuba, the Keys and South Florida through Sunday.
Bryce Tyner, meteorologist with National Weather Service Key West, said sustained winds at the Key West International Airport Saturday were recorded up to 40 mph. Saturday night, gusts were recorded between 39 mph and the upper 40-mph range, "and that was universal throughout the Keys," Tyner said.
Miami-Dade County, expected to be spared from the worst of the storm, is forecast to face heavy rain in squalls, brief gusty winds no stronger than 40 mph and hazardous marine conditions, according to the National Weather Service in Miami.
Parts of Miami-Dade were under thunderstorm advisories early Sunday. A brief tornado warning was issued for parts of Dade County until 8:45 a.m. Sunday. The warning included Kendall, Palmetto Bay and Pinecrest, according to the National Weather Service.
Among other potential impacts the region may see are flooding in vulnerable areas, isolated power outages caused by downed trees, waterspouts possible across all waters and rip currents at the beach.
A flood watch has been in effect for South Florida since 8 a.m. Saturday, the National Weather Service said. It will last until 8 p.m. Sunday.
The Florida Panhandle into eastern Alabama and western Georgia are forecast to see four to eight inches of rain Sunday, with isolated storm totals of 12 inches. A storm surge watch is in effect from Crystal River, a coastal city in Citrus County, north toward the Mississippi-Alabama border.
A tropical storm warning for Dry Tortugas has been discontinued, as has the tropical storm watch along the north-central Gulf Coast.
Gradual strengthening is forecast until the storm reaches the northern Gulf Coast, at which point meteorologists expect it to weaken and become a tropical depression by Monday night or Tuesday, according to the hurricane center.
Florida Gov. Rick Scott on Saturday issued a state of emergency for all 67 counties "to make sure that our state and local governments are able to coordinate with federal partners to get the resources they need."
"As we continue to monitor Subtropical Storm Alberto's northward path toward Florida, it is critically important that all Florida counties have every available resource to keep families safe and prepare for the torrential rain and severe flooding this storm will bring," he said.