(PM)-Hurricane Dorian is expected to make landfall early next week on the Florida peninsula. Much of the southeast will be faced with hurricane force winds, life-threatening storm surge and massive amounts of rain. Overall, a very dangerous and potentially deadly system is unfolding.
The current National Hurricane Center forecast track suggests Dorian makes landfall in south central Florida. There is still a wide range of possibilities at this point as even landfall is not guaranteed.
The ECMWF ensembles show many different possible solutions to Dorian’s track. Anywhere from re-curving out to sea just before landfall to a track in the Gulf of Mexico is possible.
I believe the most likely track takes Dorian just up to coastal Florida before slowly moving inland just east of Lake Okeechobee. Then a turn north will come soon thereafter as a ridge to the west will stop the forward momentum of Dorian.
The track has not changed much, however, the forward speed projection has. Dorian will slow considerably upon its arrival into the Bahamas and may possibly stall out. This will give it more time to strengthen as the waters are warm and wind shear is low.
Many models bring the storm to a near grinding halt in the Bahamas. This will create a worse situation as any areas impacted will feel the effects longer.
The National Hurricane Center projects that Dorian will be a category 4 hurricane upon landfall in Florida. Everything that I see suggests the same if not worse.
Usually with a storm stalling over the open ocean it will weaken as the storm uses all the ocean energy and up-wells cooler waters. As you can see with the map above, the heat of the ocean in the Bahamas travels deep beneath the surface.
Even with a slowing storm up-welling will not do much to stop the strengthening of the storm.
Wind shear across the Bahamas and dry air will not be a problem as shear has relaxed and a moist environment is in place. Unfortunately there is no factor in place that I see that will prevent Dorian from becoming a category 4 or even 5 before landfall.
The HWRF model, used primarily for hurricanes, is showing a storm down to 930mb with winds topping 125kts. I fear that the impacts may be even stronger than this but that will be determined in the coming days.
Currently, the worst impacts are expected to be on the southeast Florida coastline where winds could exceed 140mph. Gusts could potentially be higher than that depending on the strength of the storm. Expect weak houses to be leveled, power to be out for weeks and some areas be uninhabitable from the high winds.
With such a slow moving cyclone, rain and flooding will be one of the biggest issues faced. The ECMWF model above is predicting upwards of 20-25 inches of rain in some areas. Considering much of Florida is swamp-like, it will not cause much rain for major problems to occur.
Storm surge will be present but will not be too catastrophic as slow moving storms move less water. This is because they have less forward moment to push the water into the coastline.
If you live along the coastline in the threat area listen to local officials and consider evacuating. All of the southeast coast still needs to be on watch for changes in the forecast and monitor potential impacts. Best of luck to all those in the way of Dorian. – Michael Barletta