Wednesday, August 24, 2016

Tropical Storm Gaston and the Atlantic Blobette: August 23, Update A

Ice cream. Oh joy. :-) 

Tropical Storm Gaston
As expected, Gaston is now officially a mid-t0-strong Tropical Storm with winds of 65mph (central pressure estimated to be 1002mb). His vorticity (circulation) has continued to strengthen today throughout the troposphere and actually, I think he is already a weak cat 1 hurricane (cat 1 range: 74-95mph). You can even see some nice structure in the satellite images: 

The convection is pretty good, although he is still slightly inhibited by the Saharan Air Layer. The NHC will most likely upgrade him to a hurricane tomorrow. 

He is currently at 14.7N, 37.1W, heading WNW at 17mph. Uh-oh! It looks like in the last couple of days NOAA has removed the websites that had the pressure maps that I consulted (it now says 'This service is no longer available'). I will have to find another source! What a pickle!! And after over 15 years of using that website!! For now, this means that I will not be able to asses the track (although I have to say, the NHC are really very good at the track at 1-2 days out now).  For today, the official track takes Gaston east of Bermuda. The track has been relatively consistent after 5 days, so I will assume that the NHC are on the ball with that.  

Atlantic Blobette
I think this Blobette should already be named (TS Hermine) because her vorticity (circulation) is quite strong in the lower half of the troposphere. But for now, she remains officially a Blobette at around 17N, 67W, heading WNW at 15-20mph.  Regardless of what she is (ahem, Tropical Storm, ahem), those Islands in the Caribbean are getting a toot of rain:

The convection is certainly not well formed, but it is quite strong with the red areas representing areas of strong thunderstorms. 

Oh, and before I wrap up there is one more thing. Whoever has that Zika virus in St. Peters-'bug' (Florida) better stop it right now and put it back where you got it. The CDC is not very happy with you. There, I think that's about it for today.  Time for a bit more ice cream I think. :-) 

Ciao,
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.

Tuesday, August 23, 2016

Tropical Depression Fiona, Tropical Storm Gaston, and the Atlantic Blobette: August 22, Update A

"Rather a busy day today Phipps... distressingly little time for sloth or idleness." - For Lord Goring, myself, and Mother Nature apparently! She has 3 storms (possible storms) in the Atlantic and another 5 storms (or possible storms) in other basins.

Tropical Depression Fiona
She is really struggling now. Although her wind speed is 35mph, central pressure 1010mb, and her convective activity keeps trying to gain ground (or sea to be more accurate), the circulation (vorticity) continues to deteriorate. She only has a signal in the lower level of the troposphere, with nothing in the middle levels (as you can see in the maps below). She is currently around 25.5N, 62.3W, heading WNW at 15mph. There may be some swells on the eastern US seaboard and Bermuda, but not too much more. This will be my last update on Fiona unless that circulation picks back up. 

Tropical Storm Gaston
Ah, Gaston... not quite a beauty, not quite a beast (yet)! :-) Gaston is currently quite a weak storm with winds of 40mph, central pressure of 1005mb. He is at 12.6N, 30.7W, heading WNW at 18mph. He has just left the general Cape Verde Islands region in eastern Atlantic, so he has a long way to travel and therefore a lot of potential to become a hurricane. His convection is still developing, although you can see quite a nice structure beginning to form:

Looking at the vorticity gives us a good idea of how strong he is. Here is the vorticity (circulation) map (from the U. Wisconsin website) in the lower troposphere (850mb): 

This is great because you can see the difference between three storms at three different intensities! First, you can see the low level circulation that is Tropical Depression Fiona (conveniently marked by the 'L'). Around 30W, you can see a big red splodge which is Tropical Storm Gaston, marked by the sign for a storm. And you can also see another blobette on here (in the Atlantic, east of the Caribbean) which I'll talk about next. 

Now if we look at the comparable map showing how much circulation or vorticity each of these systems have in the middle troposphere (500mb), we can see how strong they really are:

The only one that now jumps out at us is Tropical Storm Gaston! Fiona and the other Atlantic Blobette have pretty much vanished. Based on this, I would actually say that Gaston is stronger than the weak storm the NHC have him as - 40mph is barely a Tropical Storm (TS range: 39-73mph). I actually think he is a mid-to-strong intensity Tropical Storm with winds of around 60 mph-70 mph because he already has a vorticity signal in the upper troposphere, which means he is approaching hurricane strength. The only reason I don't think he is a hurricane yet is because his convection hasn't quite caught up - and that is partly because of that lovely Saharan Air Layer which is inhibiting his development:
He is certainly over waters warm enough to feed him (temperatures are above 27 deg C, with the upper 50m warmer than 26.5 deg C) and there is very little wind shear. 

I'll have a look at possible tracks tomorrow. 

Atlantic Blobette
There's a small blobette at around 16.5N, 55W, heading WNW at 15-20mph, but as you can see from the vorticity maps above, she is quite weak at the moment. However, she is heading into an area of low wind shear, she is moving away from that dry and dusty SAL, and water temperatures are warm (and getting warmer) ahead of her. All signs that she will most likely get a bit stronger. The NHC currently think she will be a Tropical Depression by Friday, as she approaches Puerto Rico and Hispaniola. 
I forecast a bit of rain on some of those islands so dust off the spiderwebs from your wellington boots. 

The next name on the list is Hermine. Not Hermione. Yes, I was hoping too. 

More on Gaston and the Atlantic Blobette tomorrow. 

Night from California, where our warnings are like this ... 

:-) (thanks to Trent F. for sharing that one). 

Toodles,
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.

Monday, August 22, 2016

Tropical Depression Fiona and the Atlantic Blob: August 21, Update A

Bit of a tricky day in the weather world today!  Japan got hit by Tropical Storm Mindulle with winds of 60mph: 
By the way (part one)... if you want to know what is happening with Typhoons as they are known in the Western Pacific, I would recommend following Robert Speta on twitter (@robertspeta), which is where I got the above image from.

TS Mindulle is closely followed by quite possibly the coolest named storm in history... Tropical Storm Lionrock! I am not jesting! :-) Great name (although I'm sure that is a translation of its proper name)! (It also appears to be currently heading for Japan, alas).

By the way (part deux ;-))... although we call tropical storms that have winds greater than 73mph 'Hurricanes' in the Atlantic and Eastern Pacific, the exact same storm type is called a Typhoon in the Western Pacific, and a Cyclone in the Indian Ocean. So whenever you hear about a Typhoon (or SuperTyphoon) or a Cyclone, you'll know exactly what it is.

Speaking of the Indian Ocean, also today - massive flooding in India resulted in a number of people who died, and 15,000 who had to evacuate. 15,000! 

Meanwhile, Gale force winds hit the UK today - these winds were stronger than those in Tropical Depression Fiona, whose winds are currently around 35mph. 

And to round out some of the world weather today, slightly closer to my current home are the California Fires! Fortunately not too close to where I live, but pretty massive and threatening nonetheless!

In the Atlantic, things are looking a little calmer as far as Fiona is concerned. She was weaker and they did downgrade her today to a Tropical Depression, with winds of 35mph, central pressure 1008mb. She is currently at 23.8N, 56.6W heading WNW at 18mph. She does look like she's trying to get back on track though (haha... all puns intended):

The burst of new convection is not a surprise because she is still over very warm ocean water with the upper ~75m warmer than 26.5 deg C, and also because she is emerging from the influence of the Saharan Air Layer that I mentioned yesterday. She is also heading into lower wind shear so there is a chance that she will re-strengthen although she has very little circulation (vorticity) in the middle of the troposphere at the moment. One can almost hear her say "I'm not dead! ... I'm getting better!" ;-) (Monty Python). Definitely one to keep an eye on for another day at least. 

Farther east, there's a new blob in the Atlantic just south of the Cape Verde Islands. This came off Africa a couple of days ago and has got some circulation in the lower half of the troposphere - although the lowest levels are not very well organized yet. However, I think this will be a Tropical Storm soon and the NHC have given it an 80% chance of formation which I agree with. It also has some convection, which also appears to be strengthening: 

The next name is Gaston. Oh dear, I feel a song coming on... 

More tomorrow.
Ciao,
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.

Sunday, August 21, 2016

Tropical Storm Fiona: August 20, Update A

I see that TS Fiona is still out there. Of course she is, it's the weekend isn't it? ;-) She's a persistent little thing (and has the potential to get a bit bigger - although for now she remains weak). 

She is officially at at 21.7N, 50.1W, officially heading NW at 15mph - although the satellite images show her center very clearly to be currently at 22N, 51W. Winds are officially estimated to be 50mph, central pressure is 1004mb, which still means she is a weak Tropical Storm (TS range: 39-73mph). I think she may now be weaker than this for a couple of reasons... 

First, she has very little convection, and it is all to the east of the center. If we look at her infra-red satellite imagery, we can see the point where the convection got spectacularly removed from the center of circulation: 
This is because she is facing some strong wind shear. However, the wind shear looks like it will die down in the next day or so, which means she has a chance to get a little stronger again. 

Second, there is very little organized circulation (vorticity) in the middle and upper troposphere. Although there is some, it looks like she is part of a front instead of a stand-alone system. 

So why did her convection vanish? The sea surface is warmer than 28 deg C, and the upper 75 m of the water is warmer than 26.5 deg C - both suggest that she has enough to maintain strong convection (rain and thunder and stuff (technical jargon! ;-))), her convection just went poof (yes, it may even have made that sound). I think the reason is because she is encountering a layer of dry and dusty air from the Saharan Desert (goes by the ingenious name of the 'Saharan Air Layer' (SAL) :-)), which you can see as the red areas on this map:

<Forecasting Tool Alert!>This SAL map is from the fantastic University of Wisconsin website: http://tropic.ssec.wisc.edu/tropic.php, should you want to have a look for yourselves (and I'm sure you do! :-)). This is the same website that has the vorticity maps I talked about in an earlier post. To find the SAL map, click on the turquoise colour block in the lower map for the North Atlantic and in the drop down menu (amongst a number of things) you will see 'Saharan Air Layer Analysis'.  Easy peasy! <End Forecasting Tool Alert!>

It does look like she will emerge from the SAL soon thought. If she still has some circulation, there is a good possibility that the convection will pick up again. We'll have to see what toll this dry 'spell' has taken.  

As for her track - that is uncertain as far as I can tell because we don't have good data over the ocean and also because she is such a weak storm. There is high pressure to her north, which suggests that she would move generally westward or WNW for now, but I would have to rely on the NHC who are using models at this point. Maybe the pressure field maps will improve tomorrow. I'll keep checking. 

That's it for tonight! 
Ciao,
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.

Friday, August 19, 2016

Tropical Storm Fiona: August 18, Update A

I'm doing a survey (for my own nefarious purposes of course ;-))... which movies are the first to pop into your head when you think of Space themed and Ocean themed movies? Let me know! 

Oh yes, and we're here to discuss Fiona! She's a well-behaved bonny lass (as are all the Fiona's I've ever met :-)).

She is currently at 17.1N, 41.8W, heading NW at 8mph. Wind speed is officially 45mph and her central pressure is 1006mb. She is still a weak Tropical Storm (TS range: 39-73mph) and I don't think she will get much stronger for a few days because she is running into some wind shear. In this, I agree with the NHC. 

She is already weaker than she was yesterday. The circulation (vorticity) in the middle of the troposphere has decreased and so has the convection:

It looks like she may avoid Bermuda after all, although that partly depends on if she does re-strengthen in a few days or remains weak. 

And that's it for today. :-)
Ciao for now!
J.

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

-------------------------------
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.

Thursday, August 18, 2016

Tropical Storm Fiona: August 17, Update A

Woohoo, it's wine o'clock! Umm, I mean it's time for Tropical Storm Fiona! ;-) 

She has been slowly developing over the last few days, and is now a fully fledged Tropical Storm with officially whopping winds of 40mph (TS range: 39-73mph), central pressure of 1006mb. Her convection has improved in the last few hours, as we see from the infrared satellite images:

But her vorticity (or circulation if you prefer) has decreased. Although it is strong throughout the lower half of the troposphere, it looks like is not as strong as it was earlier today (if you have forgotten all about the troposphere and atmospheric structure check out this Science Alert! from waaaaay back in early June). This suggests that she is a relatively weak Tropical Storm - so I would estimate somewhere in the 40-50mph range at the moment, which is in agreement with the NHC. 

She is at 15.5N, 39W, heading WNW at 16mph. She's heading no-where in particular... oh, except for that little island called Bermuda perhaps:
Honestly, do you guys have a Hurricane magnet you set up every year? For such a relatively small land mass in such a vast ocean, how do you manage to attract so many storms?! ;-) Actually, it is really too soon to tell where she is heading, although that general direction is quite likely given the pressure fields. I will hopefully have more to say on this tomorrow. 

Meanwhile, elsewhere in the general Atlantic area are the Olympics. As I marvel at the greatness of these events and the amazing athletes that compete, I wonder where off the coast of Brazil are they doing the 'Seahorse Racing' event ... 
:-) This is from a neat book by Isaac Asimov, Futuredays: A Nineteenth Century Vision of the Year 2000. It's a great collection of paintings from around the 1900s showing what artists thought we would be doing in the year 2000. You can see some more and get some of the history here at The Public Domain Review website. (Where is my flying car?).

I'll return tomorrow... (must actually catch up on the news from the massive flooding in Louisiana - and if you are looking, here is the most comprehensive list of ways to help that I could find).

Toodles,
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.

Monday, August 08, 2016

Gulf of Mexico Blobette and Atlantic Blob: August 7, Update A

Things I would like to share since yesterday:

a. Tropical Storm Javier is, indeed, churning away in the eastern Pacific as expected. Alas, mudslides from Tropical Storm Earl did a lot of damage - rain caused mudslides in Mexico that unfortunately resulted in loss of life. :-(

b. There was rain over Florida, Alabama, and a few other states in the Southeastern US, but the Gulf of Mexico Blobette has moved over land and therefore should vanish 
c. The Atlantic Blob isn't doing too much either.
d. The movie Dirty Rotten Scoundrels is a remake!!! I own a DVD of that movie because I like it so much... so how come, after all these years, I did not know this?? The original, Bedtime Story, starred David Niven, Marlon Brando, and Shirley Jones. How can I get my paws on this?!? (apparently not through Netflix streaming...). 
e. The Olympics are fabulous!

That's about it. I'll be back when Tropical Storm Fiona looks like she's going to make an appearance. Or possibly before.  

Toodle Pip!
J.  

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

-------------------------------
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.