Weather Nerd

Hanna likely to hit South Carolina as Cat. 1


No time for a full update this morning, but Alan Sullivan does a good job summarizing the latest on the storm of most immediate concern, Hanna, which appears destined for a landfall in South Carolina very late Thursday or very early Friday — just a few hours after John McCain’s acceptance speech at the Republican Convention in St. Paul. Luckily for all concerned, Hanna will likely be a relatively weak hurricane. Sullivan writes:

Tropical storm Hanna is now being tugged by a deepening upper trough. This in turn has jutted from a larger polar low that has been spinning fiercely off New England. The southwest-bound trough is plucking Hanna northward away from Hispaniola. Later, as an upper low cuts off near Cuba, Hanna’s course will turn more to the northwest. What NHC is not saying right now — perhaps to avoid any confusion among the public — is that ensnarlment with the polar system will almost certainly impart a high degree of asymmetry to Hanna. On satellite images it will look more like a hybrid storm, or even a nor’easter. This means that heavy weather will probably be displaced north and east of the center during South Carolina landfall. It will also hinder intensification. We can be confident that Hanna will only be a minimal hurricane. The model consensus turns Hanna rather sharply northeastward soon after landfall, as another polar system moves through the Great Lakes. Hanna will then sweep into the northeastern US as a powerful rainstorm, with strong winds along the coastal waters. Bottom line: plenty of inconvenience, minor damage. Storm preparations should commence on the Carolina sounds and up the Delmarva. Those areas may take the brunt of Hanna’s winds, which will blow from southeast and south as the storm center passes just inland. Tornadoes will also be a threat along the coastal plain.

He also writes a bit about Ike and Josephine. I’ll have more to say about those systems — especially Ike, which is likely to become a hurricane today — later.

Meanwhile, in New Orleans, there is growing frustration about the slow pace of evacuee re-entry, post-Gustav. To some extent, this is inevitable — but to whatever extent it is avoidable, it’s a real problem, as it guarantees that future evacuations will be less successful. Times-Picayune writer James O’Byrne sums up the sentiments perfectly in a column titled “Next time, we won’t leave.” There is a lot to chew on here, and I want to give it a full and thoughtful treatment, which I don’t have time to do right now. So, again: later.