Hurricane Isaías approaching Florida, Tropical Depression 10 forms

Hurricane Isaías is still tracking over the Bahamas, and has encountered that dry air and wind shear that I mentioned in yesterday's post. The combination of those two things has unquestionably overwhelmed the boost given by very warm ocean water.  In this long radar loop below, we can see a lack of symmetry, and an erosion of the western and southern portions of the hurricane's eyewall and rainbands as it approaches Andros Island. In short, it's having serious problems, which is great news for Florida.

There are long, updating radar loops available at http://bmcnoldy.rsmas.miami.edu/tropics/radar/

As of Saturday morning, Isaías is a Category 1 hurricane with 80 mph peak sustained winds. It is forecast to weaken some more as it heads north, but will still be impactful along the entire US east coast over the next 4-5 days, particularly in the storm surge and coastal flooding department. Hurricane warnings are in effect for the northern Bahamas and much of the eastern Florida peninsula. The center of the storm will track extremely close to the Florida coast, perhaps making landfall, or just missing, very similar to Matthew in 2016. And like Matthew, it seems likely to make landfall in South or North Carolina as a strong tropical storm or Category 1 hurricane.

Zooming in to just the next three days and the tropical storm wind speed probabilities and their arrival times, we see the highest risk along the east coast of the central Florida peninsula, but 30%+ all along the southeast coast.

Places near the center could see 2-4 inches of rain, and 2-4 feet of storm surge along that same part of the east-central peninsula. Fortunately, there is not any reasonable model guidance to suggest that the Carolinas will be dealing with a strong hurricane when it arrives on Monday.  It's also moving fast enough that widespread flooding is not a big concern.

In the far eastern Atlantic, near Cabo Verde, Tropical Depression 10 formed on Friday evening.  It is not expected to last very long, and may never reach tropical storm status. Also, a strong tropical wave centered about 600 miles east of the Leeward Islands is likely to develop this week. As of now, model guidance is in good agreement on it tracking toward the northwest and turning northward before reaching the U.S. 

Either one of these two could be the recipient of the next name on the list, Josephine. The record earliest date for the "J" storm to form is August 22 (Jose in 2005), so there is no doubt at all that 2020 will crush that record too.

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