Ernesto moved ashore last night, first in Islamorada, then later again on the border of Miami-Dade and Monroe counties. Even though Ernesto has been over land for about six hours or so now, Ernesto is still maintaining tropical storm force winds and fairly strong convection (Figure 1). This is most likely due to Ernesto moving over the Everglades, a swampy, warm water source. While obviously not as good as the Gulf of Mexico, it's also not nearly as bad as moving over the mountains of the Greater Antilles.
As for where Ernesto goes from here, it appears that Ernesto will be accelerating to the north-northeast this morning and early afternoon, most likely moving off the Florida coast between Daytona and Cape Canaveral. Once off the coast, Ernesto will have the opportunity to reintensify over the warm waters of the Gulf Stream before making another landfall near the North Carolina-South Carolina border (Figure 2). The computer models are in good agreement with this forecast, and the next landfall should take place Thursday night and into Friday morning (Figure 3).
The intensity forecast is slightly tricky. Most of the models have Ernesto coming ashore along the Carolinas as a moderate tropical storm (Figure 4), which is the most likely scenario. However, the warm waters of the Gulf Stream have been known quickly to spin up tropical cyclones. I'd give it about a 10% chance that Ernesto makes landfall as a hurricane in the Carolinas. As always, stay tuned to the StormTrack for more.