Satellite loops this morning show that the disturbed weather in the NW Caribbean is now reached sub tropical storm strength and thereby named Alberto. The structure of the system appears to have a sheared look to it though we are seeing some convection developing closer to the circulation center. Dry air is evident on the back side of the system as well.
The eastern side is seeing a gradual expansion showers and thunderstorms and they appear to be heading for South Florida. Heavy rains are likely to spread northward over Florida this afternoon and on Saturday as Alberto heads into the Gulf of Mexico. The threat to the Gulf Coast is also increasing from NW Florida to SE Louisiana later Sunday and Monday as Alberto crawls northward. Also there is time for this system to strengthen as conditions will be somewhat favorable over the weekend. Alberto will be in an environment of less wind shear and water temperatures that are in the lower 80s. The major threat here remains rain and the rainfall amounts above are through Sunday evening and likely conservative for most areas. Often times local amounts can be easily double what is forecast. Alberto becomes the 3rd tropical or subtropical system to develop in the Atlantic Basin in the last 7 years. May is usually a quiet month with statistically 1 storm about every 10 years.
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