Potential Tropical Cyclone #4: The area of disturbed weather now located just south of central Cuba was designated Potential Tropical Cyclone #4 earlier today. Even though this system is not quite yet organized enough to be called a tropical depression or a tropical storm, it is very likely to become one and because of this it has been designated a Potential Tropical Cyclone. It also gives the National Hurricane Center the option to post watches and warnings, which they have done.
One important item in analyzing PTC 4 is that the center of this system seems to be located just to the south of central Cuba putting it to the south of where most of the model guidance have forecast it to be. This opens up the very real possibility that it could lead to more time over the very warm waters of the extreme northern Caribbean leading to a stronger system in the southeastern Gulf of Mexico by late Saturday. It could also mean more time over the waters of the eastern Gulf of Mexico during Saturday night and Sunday leading to the potential of it being a hurricane by the time it comes ashore near the Big Bend area of northwest Florida or in the far eastern Florida Panhandle on Sunday night.
The forecast becomes more uncertain once PTC 4 moves ashore into north Florida and southeast Georgia later Sunday night and Monday morning as the steering winds are likely to break down around this system. This is likely to lead to PTC 2 slowing way down in forward speed as it tracks from near the Georgia coast through the South and North Carolina coastline. Not only that but the environmental conditions are likely to be favorable for strengthening while this system crawls over the very warm waters near the Carolina coastline. This has the potential to lead to this system being a strengthening hurricane that doesn’t want to go anywhere during the first half of next week.
The model guidance are pretty divergent with each other in their forecasts of this system with the GFS model forecasting a pretty slow track from just offshore of the coast of Georgia on Monday morning to eastern North Carolina by Wednesday evening all strengthening while it does this. The European model, on the other hand, forecasts a system that takes a track near the Georgia and South Carolina coasts from Monday through Wednesday before looping back inland into the area between Charleston and Savannah on Thursday.
This makes for a very difficult forecast in terms of both track and strength during the first half of next week. Know though that a strengthening hurricane with potential impacts to much of coastal areas of Georgia, South Carolina and North Carolina is a real possibility that lasts for an extended period of time during the first half of next week.
Here Are My Thoughts: I think that we should probably see the center of PTC 4 pass just west of the lower Florida Keys by Saturday afternoon and evening and it could very well be a tropical storm at that point, especially if it stays over the open waters of the far northern Caribbean tonight into Saturday.
During the day on Sunday, Tropical Storm Debby is likely to be strengthening as it tracks just offshore of the west coast of Florida with a landfall somewhere in the area between just east of Apalachicola and Cedar Key late Sunday night as a borderline tropical storm-hurricane.
A track that takes Debby-to-be across north Florida and south Georgia looks plausible at this point during the day on Monday with it moving back over water along the Georgia coast by Monday night.
As we get into Tuesday and Wednesday, a meandering and very slow moving strengthening hurricane is expected to track near or right along the coast from Savannah on Tuesday to Charleston and Myrtle Beach on Wednesday.
Beyond this, the forecast uncertain becomes extremely high as there are equal chances that this system could slowly track towards eastern North Carolina and then just offshore of the New England coast late next week or it could loop back inland into coastal South Carolina or southeastern North Carolina.
It needs to be emphasized that tropical systems in a weak steering flow environment like we’re going to have next week near the Carolinas have very high track error rates and very low forecast confidence. You need to expect the unexpected with these types of forecast scenarios.
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The next tropical weather discussion will be issued on Saturday.