Potential Tropical Cyclone Nine

The track models are in good agreement for the first 3 days of the forecast. The new NHC forecast track has been shifted westward during that period, mainly due to the westward adjustment of the initial position, but it is also a bit slower than the previous prediction based on the latest guidance. There is significantly more uncertainty in the track forecast after day 3, but at the very least it appears that the system will slow down considerably and perhaps even stall near the coast of South Carolina.

Interestingly, the 18z GFS and ECMWF solutions no longer show the system moving inland over the southeastern U.S. and have come more in line with their respective ensemble means, as well as the HCCA consensus aid and Google DeepMind mean. For this new forecast, a very slow, nearly stationary motion is shown on day 5, with perhaps some hint of the start of a northeastward motion. That said, even if the system stalls just offshore, it would still be large enough to cause wind and coastal flooding impacts along the southeastern U.S. coast, as well as heavy rainfall/flooding concerns in inland areas. Global models suggest it will still take another 24 hours or so for the system to develop a well-defined circulation and organized convection to be classified as a tropical depression.

1. The disturbance is forecast to become a tropical storm this weekend and bring tropical storm conditions to portions of the central and northwestern Bahamas, where Tropical Storm Warnings and Watches, respectively, are in effect. Rainfall associated with this system will impact eastern Cuba, Hispaniola, Jamaica, and the Bahamas through the weekend.

2. There is an increasing threat of heavy rainfall early next week from coastal Georgia through the Carolinas and into the southern Mid-Atlantic states, which could cause flash, urban, and river flooding.

3. The system is expected to be at or near hurricane intensity when it approaches the southeast U.S. coast early next week, where there is a risk of storm surge and wind impacts. Residents in that area should monitor updates to the forecast and ensure they have their hurricane plan in place.