Invest 96L has been upgraded to Tropical Depression Sixteen as of the 11am Advisory from the NHC. The forecast is for TD sixteen to become a Tropical storm before it gets to South Florida BUT it will most likely begin the transition to a subtropical storm. I will try to explain the difference between a Tropical Storm and a Sub Tropical storm. In a normal tropical storm – the central portion or the “center” of a storm it is a “warm core” meaning all the strongest winds will be in the center. In a “cold core” system all the winds are displaced away from the center. Also in a cold core system – all the circulation is at all levels. In a warm core system such as a hurricane, this has a pool of warm air aloft generated by latent heating. The thermal wind changes direction at some altitude aloft due to the change in the temperature gradient and you get an anticyclonic circulation at high levels above the hurricane which you see as the wispy cirrus clouds that “push away” from the center.