24 August 2016

Tropical wave over Virgin Islands presents threat to Florida, Gulf Coast

I'm on vacation this week, but given the activity in the Atlantic, I wanted to share an update with you written by Jason Samenow from the Capital Weather Gang:

Tropical wave over Virgin Islands presents threat to Florida, Gulf Coast

Throughout the week, if I don't get a chance to write an update, I will share one with you from a colleague!


23 August 2016

Fiona is nearly gone, Gaston has formed, and TD8/Hermine is on deck


The disturbance that was identified as "90L" (far eastern Atlantic) was upgraded to Tropical Depression 7 on Monday afternoon, and then again to Tropical Storm Gaston on Monday evening.  Although Gaston is expected to become the season's third hurricane sometime tomorrow, models are still in very good agreement on it turning/recurving to the north even further east than Fiona did -- so safely in the middle of the ocean.

Tuesday morning sunrise over Tropical Storm Gaston.
The western tropical wave, still identified as "99L", is the one I've been discussing that left the African coast LAST Tuesday (16th).  It is still disorganized, but is gradually becoming better organized, and is now approaching the Lesser Antilles.  The next name on the list is Hermine.

Enhanced infrared satellite image of 99L approaching the Lesser Antilles.
The morning model track guidance is shown below, and the majority of models now keep it north of the Caribbean and on a trajectory that would bring it near the Florida peninsula late next weekend into early next week (6-8 days).

The intensity is still a huge unknown since it isn't even a depression yet, but IF it starts to develop, it would have time to reach hurricane intensity and is worth keeping a very close eye on.  Some models have consistently shown it crossing the Florida peninsula and then strengthening in the far northeast Gulf of Mexico as it heads north.  It's too soon to trust any exact scenario now, but it is also prudent to be aware of the possibilities now that we're within the one-week time frame (global models have skill that far out!).



And finally, I suspect the final advisory will be written on Fiona today... it is now a small swirl essentially devoid of any thunderstorm activity.  It is not near any land.