The tropics are definitely busy as we reach the half-way point of September but we still have not had a hurricane form this month. Hermine became a hurricane on August 31 so that does not count towards September. As it stands, the systems we have seen since Hermine have all struggled with strong upper level winds and abundant dry air. That theme continues today.
Julia is milling around off the South Carolina coast and will do so for the next several days. Fortunately for flood-weary residents of the Palmetto state, strong upper level winds are keeping any solid convection or thunderstorms well away from the coast. This should reduce or even eliminate the threat of heavy rain for South Carolina for the time being. However, I caution you that Julia has done nothing but defy forecasts ever since the first advisory. In fact, the depression “should” be well inland over south-central Georgia today. Instead, it’s over the warm water of the Atlantic – more than 200 hundred miles from where it was forecast to be for today. As long as the shear stays strong, the heavy rain will remain off the coast but it’s something to monitor just in case.
The forecast is for Julia to basically sit and spin over the water south of Wilmington and east of Charleston with little overall change in strength. This should result in seeing Julia literally run out of energy and become a remnant low. This will act to take some of the heat out of the ocean which has been running above normal all summer – that could help later in the season if something of significance were to track over the same location.
Next up is tropical storm Ian. Not much to say here except it’s yet another Cape Verde storm that failed to become a hurricane despite warm Atlantic waters. It is forecast to continue to move out in to the far reaches of the North Atlantic as a large, strong extra-tropical storm system. Ian poses no threat to land areas and is only of concern to the shipping lanes along its track.
Then we have TD12 out in the eastern Atlantic. The overall area of energy associated with the depression is enormous – like a pre-typhoon low pressure area in the west Pacific. However, in this case, I do not think it will live up to anywhere near its potential. Once again conditions are mysteriously unfavorable throughout the MDR or main development region. Dry mid-level air and strong upper level winds, typical of a season like last year, remain dominant. This will keep TD12 from strengthening but will allow the energy to travel west for several days. It is possible that it could end up somewhere in the Caribbean or southwest Atlantic in a week but none of the global models indicate that it ever amounts to anything.
So for now, we have no major issues to be concerned with in the Atlantic, Caribbean or Gulf of Mexico.
M. Sudduth 10:45 AM ET Sept 15