Saturday, July 03, 2021

Tropical Storm Elsa: 3 July, Update A

The good news is that the wind is not howling (like this swirling storm inside) quite so much as before. That's right Elsa, Let It Go! (from Frozen, for the lucky uninitiated few amongst you!) ;-) 

There was some wind shear that kicked in today and that combined with some outer band interactions with Hispaniola means that she has weakened to a strong Tropical Storm with winds of 70mph (TS range: 39-73mph), central pressure 1002mb. We can see the land interaction in the satellite imagery now from the ragged formation of her convection:

It is difficult to see a center but she is currently at 17.3N, 73W, heading WNW at a whoppingly fast 29mph. As I said yesterday, it is unusual to see a storm moving so quickly in the tropics, but it is not unheard of. The last time it happened I think was in 2013 with Tropical Storm Chantal also in the Caribbean in early July, which had a forward speed of around 34mph at one point.

Her center is passing south of the southwestern tip of Haiti though, so once she gets away from the island she may strengthen a little bit more before getting to Cuba. The official forecast says she will continue to decrease in intensity and won't regain hurricane strength, although she will remain a mid-to-strong Topical Storm until she gets to Florida. I agree with this given her track looks like it will pass over Cuba. She may even fall apart a lot more quickly than the official forecast if she stays on the eastern side of the cone and over land - we've seen many storms fall apart crossing Cuba along this pathway. The more she interacts with Cuba, of course the weaker she will be. 

She no longer has any circulation in the upper levels of the troposphere, only in the lower half. This is consistent with a Tropical Storm versus a Hurricane. Also, there is continuing wind shear, so the circulation is a little skewed which means her vertical structure isn't very good either. 

And now I am going to have to go and listen to some proper music (i.e. ABBA) to get rid of the Frozen song from my head.

Toodle pip!




These remarks are just what I think/see regarding tropical storms - not the opinion of any organization I represent. If you are making an evacuation decision, please heed your local emergency management and the National Hurricane Center's official forecast and local weather service announcements. This is not an official forecast. If I "run away, run away" (Monty Python), I'll let you know. 


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