Wednesday, September 4, 2019

80 Degrees

Throughout our long wait for Dorian, we have counted for several days on its forecast turn from northwest to north, keeping it at, or east of, the 80 degree west longitude line (and more than 75 miles east of us) as it passes. (We are located at 31.9N 81.3W.) In a remarkable display of forecasting accuracy, the National Hurricane Center first said last Saturday night that the storm would arrive tonight at 8 pm at a position of 31.1 degrees north, 80 degrees west, where it would turn north and then later to northeast. So it is now 8 pm, and the storm's position is 30.9N 79.8W, two tenths of a degree south and two tenths of a degree east of the position forecast 96 hours ago. It has turned from a northwesterly course to due north. No doubt the NHC is aided by advances in technology and computer modeling, but if you have ever looked at the range of models and spaghetti lines produced by them, you will understand that a lot of ability and professionalism goes into producing these forecasts. And lives depend upon them.

Showing Division Belle and 80 degree west line 75 miles to the east
Until now, Dorian was being forced to travel northwest by an upper level ridge of high pressure near latitude 32 north, which has been gradually eroding. Complete erosion of the ridge has now caused Dorian to respond by turning north. Overnight, upper level steering should turn Dorian to the northeast. The only question is whether it will turn northeast soon enough or sharply enough to avoid a landfall along the South Carolina coast. It is predicted that it will make a landfall at least briefly near the Cape Lookout or Cape Hatteras areas, unless it is changed by coming ashore in South Carolina. After that it will be at sea heading toward Nova Scotia or Newfoundland.

We believe we have been extraordinarily fortunate with the timing of the storm and the tides where we live. Our high tide was around 4 pm this afternoon. Dorian was well south of us and barely influenced the tide. The next high tide is at around 4:15 am tomorrow, when we are hopeful that the storm will have moved north of us causing our winds to be from the north rather than the east, and perhaps eliminating any tidal surge. Importantly, the high tide tomorrow morning, without any surge, is to be a full foot lower than this afternoon's high tide.

Currently here the winds are from the southeast at 22 mph gusting to 24. It is not even raining.


No comments: