The National Hurricane Center (NHC) issued a Special Tropical Weather Outlook (STWO) Sunday afternoon on an area of disturbed weather associated with an upper-level trough – giving the disturbance a 30 percent chance of development within 48 hours, and a 40 percent chance of development within five days. It is possible that this area of disturbed weather could develop into a tropical or subtropical cyclone during the next few days before it is expected to move inland into the Florida Panhandle by Thursday. The main threat with this system, as is typical of early-season weak systems, will be heavy rains for the Florida Peninsula and much of the Southeastern United States. Residents of Florida and the southeastern United States should monitor the development of this disturbance, as several inches of rain are possible in certain areas.

Environmental conditions for the disturbance (likely soon to be designated Invest 90L) are marginal for development. Sea surface temperatures are about 25°C (77°F), which is cool but warm enough to support a subtropical cyclone (though not warm enough for significant intensification). Wind shear is currently moderate to strong but is likely to decrease during the next couple of days. The disturbance is likely to develop a weak low on Monday, and could gradually acquire subtropical or perhaps tropical characteristics while it moves little on Tuesday and Wednesday.

The 12z Sunday ECMWF and experimental FV3-GFS models predicted this system to develop into a tropical depression or storm before making landfall in the Panhandle of Florida on Wednesday or Thursday. The 12z Sunday GFS, CMC, UKMET were less bullish, only predicting a weak low pressure area to form. Several of the EPS and GEFS ensembles showed development. If this system develops into a named storm, it would become the first subtropical or tropical storm in the Gulf of Mexico during the month of May since 1976.

I will be back with another post on this disturbance tomorrow. If the disturbance becomes a subtropical or tropical storm it will be named Alberto.