South Florida braces for flooding ahead of Subtropical Storm Alberto

Governor declares state of emergency

MIAMI – Periods of moderate to heavy rain are underway over South Florida and the southern half of the Florida peninsula as Subtropical Storm Alberto moves north.

The rain will migrate north, and continue through the Memorial Day weekend. Winds will become gustier tomorrow, and some funnel clouds and isolated tornadoes are possible in the stronger squalls.

A flood watch is in effect for South Florida and much of peninsula Florida. Beware of flooded roads and creeks. The situation will continue to deteriorate over the weekend as the winds increase. Boating will be hazardous in most of Florida all weekend.

At a briefing in Tallahassee, Florida authorities urged residents to take the storm seriously and to organize water, food, medicines and other preparations. Gov. Rick Scott declared a state of emergency, which gives him wide latitude to prepare.

"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," Scott said.

The disorganized center of Alberto is near the western tip of Cuba. Dry air and unfavorable upper winds have slowed its organizational process, but the forecast is not markedly changed. It is important to note, however that forecasts of disorganized systems are prone to higher errors.

The apparent development of the center somewhat farther east (closer to Florida) means that gustier winds, possibly over 40 mph, might affect the west coast of Florida, so a Tropical Storm Watch has been issued for the west-central coast including the Tampa Bay area. This change does not affect the Miami-Fort Lauderdale area. 

By late in the weekend the center of Alberto is expected to be near the northern Gulf coast -- most likely Mississippi, Alabama, or the Florida Panhandle. Alberto is expected to be a more organized tropical storm at that time, and there's a chance it could reach hurricane strength, especially if it slows down.

The effect on South Florida will be the same. Tropical moisture will continue to be drawn up on the east/right side of the circulation meaning periods of heavy rain are expected. See the satellite picture attached showing Alberto's rough center and the bands of rain - both poised to move generally to the north over the weekend.

The forecast is for 4 to 8 inches of rain over a wide area, with some isolated higher amounts possible. See the rainfall map showing the forecast for today through early Tuesday.

The cone shows the timing of the center of the storm's movement. Notice that it will take all weekend to pass by the state. Even when the center reaches the Gulf coast, the corridor of tropical moisture is still expected to cover peninsula Florida.