The 8pm advisory just left the gates of the National Hurricane Center, and it indicates that Ernesto’s about to reemerge into the Atlantic as a 35 MPH tropical depression. It held up well over Florida, even sprouting some new developments of thunderstorm activity over the Everglades (which is largely water). Now, we turn our attention to the final leg of its journey back over the Atlantic, and a lot will come into play here. Let’s talk scenarios, with the help of a few well-placed visual aids.
I’m going to call the current Hurricane Center forecast track Scenario 1. Here’s a map below.
The current scenario takes the storm into the East Cooper/Bulls Bay region, gives it (at its present forward speed) about 18 or so hours to suck up some Gulf Stream goodness and get organized. The last forecast intensity I saw at landfall was a 50 MPH tropical storm. For the sake of variance I’ll say 50-60 MPH is possible. This would expose Charleston to moderate surge as it moves upward and deal its toughest blow to Georgetown, Myrtle Beach, and points northward. Charleston would see the so-called “eyewall” of the storm, albeit the west side. It’s worth noting, though, that the heavy rain does not seem to discriminate in this storm and will be widespread no matter what quadrant one may be in. Heavy rain is a given in all these scenarios.
Scenario 2 would emerge if the storm did not make as much of a jog to the east as predicted; i.e. it stays on its current northward trajectory.
This is worse for Charleston, as we end up directly on top of the storm or even right on the track. More surge effects, tornadoes, and other nasties would be the order of Thursday. However, given the forward speed not deviating from the forecast it would chop about six or seven hours of face time with the water out, which could have an adverse effect on intensification, so while we would be on the “wrong” side of the storm, it also would not be nearly as intense as it could be.
If by some miracle something pushes the storm more eastward, Scenario 3 could result.
A more eastward trajectory would affirm Charleston as being on the left of the track for the duration of the event, vastly reducing surge and tidal issues and eliminating the tornado threat. Heavy rain will cause flooding on its own, but it won’t be augmented by abnormally high tides. Any wobble to the right is a good, good thing for Charleston, but not necessarily so for Myrtle Beach and Wilmington, as the more time it has over the water, the stronger the storm most certainly will get. In my variation of the trajectory, Ernesto reacquiring Category 1 hurricane status prior to a landfall on the North/South Carolina border or points close would not be out of the question.
Wobbles to the left and right will drastically change the prognosis for Charleston over the next 12-24 hours. Keep your eyes peeled to that radar!
Speaking of radar…the first bands of Ernesto are now coming onshore in northern Charleston County:
We’ll get our next track adjustment and set of statements from the Hurricane Center at 11. In the meantime, I’m going to listen to Mr. Mister and set up a few things around the house. The backup batteries have been installed in the weather station so should I lose power, I’ll still be able to have some “stick time” to watch what happens with the storm.
I strongly recommend downtown residents get their cars on the second or third floors of City-owned parking garages tonight. It’s free, and will save you lots of headache cleaning or even totaling a flooded car. Trust me…