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(1/8) While the HWRF solution for #Dorian is an outlier, as it brings the storm onshore in Florida, the model may be onto something. Unlike the GFS and EURO, the HWRF is coupled to the ocean, meaning that upwelling is a considered factor, and...
(1/8) While the HWRF solution for #Dorian is an outlier, as it brings the storm onshore in Florida, the model may be onto something. Unlike the GFS and EURO, the HWRF is coupled to the ocean, meaning that upwelling is a considered factor, and...
(2/8) the model shows weakening due to cooler, upwelled waters as it crawls W. The 18z run has it initialized at 901mb, and even though that was 10mb too low, the GFS initialized it at 957mb, 42mb too high at that point. But by 00z Wednesday, the GFS is deeper than the HWRF... 
(3/8) As a result, the GFS (and EURO, too) curve it north as the hurricane deepens. The HWRF, on the other hand, shows weakening because of the aforementioned upwelling, which causes the storm to become shallower in the troposphere compared to GFS, which could be crucial...
(4/8) in terms of track. Because the storm is shallower, the storm is more reliant on lower-level steering flows. The storm curves north on the global models east of FL because a ridge over the NE Gulf causing Werly slow in upper-levels, forcing a taller Dorian away from land...
(5/8) The Gulf ridge on the HWRF is at a similar strength/position in comparison to the GFS, but it tracks further west because the storm is weaker, meaning it's more reliant on sfc flow, as said earlier. So the ridge to the NE, the main steering factor so far, pushes Dorian...
(6/8) onshore in Florida in the HWRF because it's lower in the troposphere and not necessarily because it's stronger. So even though Dorian still turns N, there is more of a Werly component to the turn, which pushes it onshore near Cape Canaveral and rides up the First Coast...
(7/8) into Georgia, before eventually emerging off near Savannah as the trough over the Midwest tracks E and pushes it along the S. Carolina coastline. This would obviously be more devastating than a track offshore, bringing storm surge, high winds, and heavy rains to a...
(8/8) wider area of coastline from the Space Coast to the Carolinas. While this track remains an outlier, I would not quite sleep on it for all the reasons listed. It could still easily remain offshore the entire US, but prepare as if the core is coming straight for you.
