After Florence’s recent eyewall replacement cycle, it has re-strengthened into a 140 mph hurricane. Strengthening is expected to continue, given that vertical wind shear will be weak, sea surface temperatures will be more than sufficiently warm, and little dry air will be present to mix into Florence’s core. In an effort to answer many unanswered questions, I’ve made a couple of maps. Let me briefly explain what they mean.
The first map includes where I believe Florence will be making its (first) landfall. Some southern shifts in track could occur; thus, I’ve included the northern South Carolina coast as a potential landfall location. Given the fairly good consistency amongst the models on landfall location, I decided not to shift the landfall threat farther south. I’ll decide tomorrow if I need to make any additional shifts southward. Locations in and around the circled region is where I am currently anticipating damage to reach catastrophic levels.
The second map includes the regions that could be impacted by Florence, whether that’s from wind, flooding, or coastal storm-surge. Most of the forecast model guidance today made a noteworthy shift westward (and even southwestward) in Florence’s track once it reaches the southern North Carolina and northern South Carolina coasts. Some of the guidance even brings the center back over water and has a second landfall occurring farther southward into South Carolina. Weak steering flow is making this a particular challenging forecast. A high pressure ridge to Florence’s east/northeast and also to its west will result in Florence slowing significantly near the coast. The pink zone is where I’m currently most concerned about; while some parts of the red zone could experience significant impacts as well. At the least, I expect those in the red zone to experience some impacts from wind and rain. If the southward trend continues, I may end up chopping parts of northern Virginia out of the red zone, but in this update, I mainly included them due to potential flooding. I’m sure modifications will have to be made to the forecast, since we’re now getting down to the county-level.
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