It is rare to have no hurricanes form in the Atlantic Basin during the month of August. It usually means the season will be less active overall but it is not a guarantee. As we end this month we will do so without seeing any hurricanes develop in the Atlantic, quite a contrast to this time last year and, I believe, it will be quite a contrast to what we will see in September.
The short of it is that the overall pattern was not favorable since about mid-July across the tropical Atlantic. Between the cooler than average sea surface temperatures and the expansive reach of the Saharan Air Layer (SAL), as well as a few other atmospheric roadblocks, we saw very little activity down in the deep tropics – and no hurricanes.
Now it looks as though things will change.
We are entering a period of the hurricane season when we normally see an uptick in development. It is also important to note that sea surface temps have rebounded quite a bit from where they were just six weeks ago. Add in a more favorable upper level pattern and the stage is set for a busy September.
Right now, I am watching two distinct areas for possible development: a tropical wave entering the Caribbean Sea and a robust tropical wave about to exit the coast of Africa.
The National Hurricane Center has already “outlooked” the system forecast to emerge from Africa and gives it a 60% chance of further development over the next five days. From the looks of the steering flow, I doubt that it will affect the Lesser Antilles but we cannot be 100% certain just yet. It’s something to watch but more importantly, it’s a sign that the Main Development Region or MDR is coming to life.
My concern is with a rather poorly organized tropical wave that is just entering the eastern Caribbean Sea. Shower and thunderstorm activity is limited but the low level energy or vorticity is impressive. The ECMWF model has been very consistent with developing this wave of energy once it gets in to the central Bahamas this weekend. Oddly, the GFS global model shows almost no development. Other models are in between which means that there is no consensus just yet. My worry is that it begins to develop in the Bahamas and then gets caught south of the large developing high pressure area over the Southeast. We’ve seen that type of set up before and it usually spells trouble. We definitely need to monitor this system.
Meanwhile, the east Pacific continues to remain very busy with tropical storms Miriam and Norman tracking westward. Miriam will turn north eventually and not be a threat to any land areas but Norman’s track could raise a few eyebrows once again for the Hawaiian Islands in about a week. I will keep on top of this situation closely considering the anxiety that the threat from Lane put upon the region.
I will have a new blog post here tomorrow morning.
M. Sudduth 2pm ET August 29