The National Hurricane Center has increased the chance for development for a broad area of low pressure in the Caribbean from 20% to 40%. This was not unexpected as the chance for the system becoming a tropical or subtropical system is greatest late in the week. The area of low pressure has also been designated Invest 90L.
An Invest is the designation given an area of interest by the National Hurricane Center. It has no relationship the confidence in a tropical system developing but rather triggers data collection and implementation of a suite of specialized hurricane computer models. It is a necessary designation to support the tropical forecast team at the Hurricane Center. Currently the track has a wide spread and only a general drift to the north is forecast. Models will become more aligned as the system see better structure.
Regardless of development the main concern is heavy rainfall potential over the holiday weekend. The system will not become a serious wind storm, although boaters should stay informed, but it will be a wet system. The closer to Florida's west coast the system drifts the wetter our weekend weather. The closer to the center of the Gulf and the stronger the storm the drier we may be this weekend.
There is still high uncertainty in the amount of rain we may see this weekend, but it is likely we will be wet. Current forecast suggest over five additional inches of rain over the weekend. Don't be surprised to see Flood Watches issued later in the week.