Friday, September 08, 2017

Hurricanes Irma, Jose, and Katia: September 8, Update A

Morning cuppa tea and very quick update…

Hurricane Irma
She has winds of 150mph, central pressure 927mb, and has been downgraded to an extremely strong cat 4 hurricane (cat 4 range: 130-156mph) and could oscillate back up, although the interaction with land is having an effect (finally!) – Cuba and the Bahamas are getting deluged though!:

She is currently at 22.0N, 75.3W, heading WNW at 14mph. The location of that turn is still unknown, so no change there – she could go up the middle of Florida (best case for rapid weakening because of interaction with land), or to either side (worst case for weakening is up the east coast and over the Florida Current/Gulf Stream, although there is some wind shear which would weaken her part way up the state):

Hurricane Jose
Hurricane Jose is now officially apparently the same as Hurricane Irma – a cat 4 with the exact same wind speeds of 150mph… however his central pressure is much higher at 942mb. They sent a plane in and then have estimated the winds from that - I think it's a little high on the estimate, but I will go with their data because in terms of the physics (ooh, lovely physics! :-)), this one is a little more complicated – the upper troposphere structure shows that he is not a tropical storm up there, but actually part of a front now (which, even in winter, can be windy):
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Strictly speaking I would say he is a cat 3 from his structure, appearance, and even central pressure, but I can see why they estimate such high winds given what is above him. Anyway, there is still some wind shear ahead of him and before he gets to the islands, which you can already begin to see as the clouds are not as symmetrical as they are for Irma – it will hopefully help to reduce his impact a bit - although he will still be a relatively strong hurricane. Even a cat 2 or 3 to the islands that have just been hit is going to be tough.  

He is currently at 16.3N, 57.1W heading WNW at 18mph:
Not a huge change to the track.

Hurricane Katia
Hmm… officially, she is a weak-to-mid-sized cat 2 storm with winds of 100mph, central pressure 975mb (cat 2 range: 96-110mph):
There isn’t a very good eye so I would actually say her winds are right around 90mph, which would make her a cat 1 storm. She is still on track for landfall tonight/early tomorrow.

She is at 21.0N, 95.8W heading WSW at 5mph:
Tea finished, work begins…
More later! 
J.

Blogs archived at http://jyotikastorms.blogspot.com/
Twitter @JyovianStorm
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DISCLAIMER: 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 the National 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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