Tropical Wave Dorian: July 27, Update A

It looks like Dorian has succumbed to the dry air and increasing wind shear and is now just waving at us from the Tropics. He is around 18.9N, 54.7W and was last spotted heading west at 24mph. A Tropical Wave doesn’t even have closed circulation… so he’s back to being a Blob. Although that’s the official verdict (the Tropical Wave bit, not the ‘Blob’ bit… that’s my version of the official verdict ;-)), I still see some circulation in the very lowest levels of the troposphere but it is diminishing so I’m ok with writing him off. He may still bring a few drops of rain to the northern Caribbean. The NHC issued their last advisory this afternoon and I will follow suit.

Meanwhile in the UK, here’s what caught my eye on the newspaper stands this morning…  

Really? Downton Abby will have a Royal twist? Really?!? (Oh, and the headline… it’s just a bit of summer rain really and has a long way to go to catch up to the tropical summer storms in Florida).

That’s all from me until Erin pops up.

Tally ho!
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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Tropical Storm Dorian: July 26, Update A

To quote Oscar Wilde: “Rather a busy day today, Phipps… distressingly little time for sloth or idleness”, so a quick update on Tropical Storm Dorian Gray. But first, a correction on yesterday’s blog, which was obviously written under the influence of too much champagne. It’s Charles Darwin who will be replaced by Jane Austen on the ten pound note, not Charles Dickens. Oopsie. J Many thanks to those who pointed it out … it has been corrected!

Tropical Storm Dorian is at 17.8N, 45.8W, moving W at a pretty rapid 22mph. His convection has really diminished during the day today, so he has been downgraded to a weak system with winds of 45mph, central pressure of 1010mb. The forecast has him as a Tropical Depression by Sunday. Sea surface temperatures are 27-28 deg C, which is definitely warm enough to sustain a storm. Wind shear is relatively weak still, so it looks like the dry air won out over the wind shear and water temperature. Here is our little Dorian in a satellite image of water vapour:

Looks like in addition to the dry air, wind shear will pick up in the next day, so I think downgrading him is a reasonable assessment.

Meanwhile, the remains of the Atlantic Blobette from a couple of days ago is lurking around Bermuda now.  Charles M. sent these two beautiful photos taken around 8.30pm last night from Bermuda:

Lovely lovely clouds! J

That’s all for today folks. Another quick update tomorrow.

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.
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Tropical Storm Dorian: July 25, Update A

Not much time to dilly dally on Dorian today and luckily the Atlantic Blobette from yesterday seems to be dwindling, so I won’t mention her again unless she has a few classic Scottish meals of deep-fried frozen pizzas served with chips and cheese and puts on a few pounds.

Tropical Storm Dorian is at 16.5N, 37.8W heading generally WNW at 18mph. It looks like he was tracking slightly north of the center of cone track yesterday and the cone has shifted so it barely skims the VIs and Puerto Rico now:

Oscar Wilde, author of ‘The Picture of Tropical Storm Dorian Gray’ wrote “People who count their chickens before they are hatched act very wisely, because chickens run about so absurdly that it is impossible to count them accurately.” However if you live in that part of the world I wouldn’t quite count those chickens yet so don’t put the wellies away for another day or two. I agree with the NHC on the general WNW track for the next few days and how close it gets to the island isn’t clear to me. The other complication is that I’m not sure that the timing of that forecast track is correct. Both the track and timing of the storm depends on the atmospheric pressure fields and they aren’t very clear for tomorrow (at least not to me).    

He has slowly been intensifying, but is still officially a mid-intensity storm with winds of 60 mph (TS range: 39-73mph), central pressure 999mb. I think this may be fractionally on the low side because the circulation has really improved in the lower half of the troposphere and there is now a small signal in the upper troposphere. This indicates a strong Tropical Storm – maybe in the 65-70 mph range. Sea surface water temperatures are a bit warmer than yesterday, but still on the cool side at around 26 deg C and there continues to be dry air to his north and west. However wind shear remains very low. Convection is strong over a small area near the center of the storm, as you can see here:

Tomorrow he will continue to move over warmer waters, so that along with the low wind shear may be enough to allow him to continue to intensify (slowly).

I’ll continue to watch his evolution tomorrow (along with one or two other people). Speaking of evolution… (heehee)… the UK 10 pound note is about to evolve as Charles Darwin will be replaced by Jane Austen. Oh no (says the scientist in me) and woo hoo (says the bibliophile in me)!

Until tomorrow,
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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Tropical Storm Dorian and the Atlantic Blobette: July 24, Update A

Moving only hours faster than the UK Royal Family, Tropical Storm Dorian was ‘born’ on Monday and named earlier today. I’m in the UK this week celebrating my brother’s wedding and, of course, happened to be serendipitously here for the arrival of Prince George Alexander Louis... so er… some of these next few updates may be a little wonky depending on the champagne-o-meter! ;-)

Tropical Storm Dorian

Tropical Storm Dorian is currently at 14.3N, 29.9W heading WNW at 21mph. He is a small-to-mid Tropical Storm with winds of 50mph (TS range: 39-73mph), central pressure 1002mb. Like the new Prince, he looks like a healthy little thing as you can see in this visible satellite image:

And in this infra-red satellite image, in which he is decidedly not Dorian Gray (you didn’t think you could get away without a literary reference did you? J):

His circulation is pretty good in the lower half of the troposphere (about what I would expect for a mid-sized Tropical Storm) and the sea surface water temperature is about 27 deg C.

His official track currently takes him in the direction of the northern Caribbean and the Virgin Islands. This is quite possible, although I think he may be tracking a little to the north of the center of cone and so there is still a chance he will curve out into the Atlantic. Also, he may not be a hurricane (or a weak one if he does become one) because he is going to pass over an area of colder water and he is heading into an area of dry air which will inhibit his development and keep him in check, even though wind shear is quite weak.  I would still polish those wellington boots in preparation if I were on those islands!

Mid-Atlantic Blobette

Another little blobette popped up today and currently resides at Nowhere In Particular, The Atlantic Ocean (around 29N, 55W). Circulation is good in the lower half of the troposphere, wind shear is not very strong, and water temperatures are 29-30 deg C, so she has plenty to help her along. The one inhibiting factor is that she is in an area of dry air. I’ll keep an eye on her, but it’s too soon to say if she’s the future TS Erin.

More tomorrow of course! Time for another celebratory glass and some munchies.
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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Tropical Wave Chantal: July 10, Update A

Well if only all the storms this year were that easy! It looks like the wind shear and dry air stopped Chantal in her tracks today and the NHC issued their last advisory on her at 5pm EST. The infrared satellite image still shows a large area of convection primarily over Hispaniola:

She’ll still generate some drops of rain as she winds down. If she had a center I’d place it somewhere between the Dominican Republic and Cuba. However she doesn’t have a closed circulation and therefore by definition she is merely a Tropical Wave, not even a Depression (which requires a closed circulation and winds of 17-38mph). I’ll still keep an eye on her because although the circulation is not as cohesive there still is some, the wind shear is dying down again, and the water is still warm. Of course, counteracting this is the dry air and her interaction with bits of land here and there so I’m only keeping one eye on her while I do other things. ;-)

For now this is my last entry on Chantal. I celebrated earlier with a nice glass of the old vino. Speaking of science (sort of) and wine, it turns out that I’m a wine connoisseur: "Wine-tasting: it's a junk science" . Phew. Good to know that all these years of dedicated wine-drinking practice have not gone to waste!J

I’ll be back when Dorian shows his never-changing face.

Night night!
J.

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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Tropical Storm Chantal: July 9, Update A

Today’s entry is brought to you by carrier pigeon and a bowl of yummy ice cream. J

Tropical Storm Chantal is currently at 15.3N, 66.2W heading WNW at an incredibly impressive 28mph (this is unusually fast for a tropical storm but is the case with this one!). She moved according to plan today and tracked generally westward, passing between the windward islands of Martinique and Saint Lucia. Martinique had the worst weather with plenty of thunderstorms as you can see in the infrared satellite image from this morning – there is an island somewhere under that bright red target!

(refresher Technical Alert! on deciphering infrared satellite imagery here.)

Here’s the radar loop from Martinique this morning which quite nicely shows her center of circulation passing by (ooh … moving pictures, go get your popcorn… it’s better viewing than the last Star Trek movie! ;-)).

She slowly intensified as expected and is now a mid-to-strong Tropical Storm with winds of 60mph (TS range: 39-73mph), central pressure is 1009mb. The islands took a little steam out of her (puns always intended, especially the geeky science ones J), but she is now firmly in the Caribbean where the sea surface water is over 30 deg. C (toasty!) and the upper 70-100m is warmer than 26.5 deg. C. Circulation is good in the lower half of the troposphere but it looks like wind shear will begin to increase tonight/tomorrow and, although there isn’t much dust, she is still surrounded by dry air so I don’t think she will intensify too much (I agree with the NHC on this), and may even weaken tomorrow.  

I think she has been tracking a little west of the center of cone track because there is high pressure to her north. This will take her a little south of the current projected path and the forecast track may move to the west. I feel a <Science Alert!> coming up! You have been warned! ;-)

<Science Alert!> Storm tracks: In the northern hemisphere 'things' (technical jargon ;-) ) tend to move clockwise around high pressure systems, and counter-clockwise around low pressure systems. For example, a tropical storm has low pressure in the center so winds move counter-clockwise (or anticlockwise if you prefer) around a storm. Similarly, tropical storms also move around larger pressure systems. There is generally a region of high pressure that likes to hang out over the Atlantic, sometimes called the Bermuda High or the Bermuda-Azores High. You can imagine it as a big clock face over the Atlantic, like this:

As storms cross the ocean, they move westward along the six o'clock region. As they turn WNW and NW they are moving from 6 to 9. Then they move N and NE, from 9 to 12. Of course, this imaginary clock face isn't nice and round, nor does it stay in the same place (otherwise forecasting the track would be easy peasy :-)). It's like a Dali clock face, with wiggly bits (more technical jargon ;-)) that are always moving:

Sometimes this high pressure stays out in the Atlantic and we don’t see many storms making landfall (which was the case for most of 2003), and at other times this high pressure extends across the Caribbean and storms end up in Central America instead of turning north. This is why I will sometimes talk of 'pressure fields' when I talk about the track - I am referring to the large scale atmospheric pressure fields. <End of Science Alert!>

That’s about it for today...my carrier pigeon can’t carry any more! ;-) I’ll be back with more on Chantal tomorrow.

Ciao for now,
J.    

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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Tropical Storm Chantal: July 8, Update A

I am writing this using semaphore because apparently, as of July 1, all computers and smart phones that are connected to the internet have accidentally been banned in Florida: http://www.huffingtonpost.com/2013/07/08/florida-banned-computers_n_3561701.html. Oopsie. Yesterday’s update was in smoke signals, in case you were wondering.

It looks like the NHC agreed with my assessment yesterday morning after all and upgraded our little Atlantic blobette from a 40% chance of development to Tropical Storm Chantal last night. Well done. That gets my seal of approval. ;-) She was not a storm that rapidly developed… just one that was rapidly upgraded!

Cute Chantal is officially at 12.4N, 56.1W heading WNW at a brisk 26mph. She’s a weak-to-mid strength storm with winds of 50mph (TS range: 39 – 73 mph), estimated central pressure 1010mb. I am not 100% sure I agree with the location of the center at the moment. I don’t have the right data, but it looks like the center could be a little east of the official location. This means that the center of cone track may be a bit off too, but the overall cone seems about right (for the next day at least) – so Barbados, get your raincoats out! I do think she will continue on a more westerly track until she gets into the Caribbean.

She is going over an area where sea surface temperatures are 28-30 deg C and the upper 100m of the water column is warmer than 26.5 deg C, which means she has plenty of warm water to sustain her and allow for some growth. She is an area of low wind shear, which will also allow her to grow. Although she is surrounded by dry and dusty air as you can see in this satellite image of water vapor, it’s not enough to stop her and I think she will continue to slowly grow.

I’ll be back with more on Chantal tomorrow, which will of course be sent by morse code over the wireless.

In the meantime, to continue celebrating the men’s singles championship at Wimbledon, today’s Tennis Trivia: Agatha Christie is credited with the first use of the phrase 'tennis-pro' in her 1942 novel The Body in the Library. (Thanks to Literary Interest (@InterestingLit) for that one!)

Toodles,
J.

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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Atlantic Blobette and Men's Single Wimbledon Championship: July 7, Update A

Here we are at the second annual ‘Murray vs that other chap Wimbledon Gentlemen Championship Match blog post’. To show my support I’m having british pancakes with a nice cup of tea. Murray just won the first set! This is such an exciting match that I’m already on the edge of my seat!

So, after a nice quiet few weeks I see that there’s a cute little blobette in the Atlantic.

She is heading due west at about 25mph and from this satellite visible image it looks like she is centered around 8N, 43W. Although the official verdict gives her a 40% chance of development in the next 48 hours, I think she may already be either a Tropical Depression or even possibly a Tropical Storm (next name is Chantal) because it looks to me like the circulation is pretty good over the entire lower half of the troposphere (<jargon alert> see here for description of troposphere: http://jyotikastorms.blogspot.com/2013/06/gulf-of-mexico-blobette-june-4-update-a.html <end jargon alert>).

(YES! 2^nd set to Murray!! J - Fred Perry, in 1936, was the last British man to win the Wimbledon singles championship!)

She is actually quite far south for a tropical storm at that longitude but it’s too soon to say where she will make the curve to the north because she’s a few days away from the Caribbean. You can see where she is relative to land in this infrared satellite image:

For now it looks like she will continue westward because there is an area of high pressure to her north. I’d get ready for a bit of interesting weather if I were on the Windward Islands.

(Goodness me but there are a lot of people in suits and ties at this Wimbledon final.)

Wind shear is quite low and the sea surface water temperatures are warm enough at 27-29 deg C, so I expect she will continue to develop slowly. The only inhibiting factor I see is the Saharan Air Layer (SAL) which is to her west and north. <Rather Obvious Jargon Alert!> Saharan Air Layer (SAL): This is dry dusty air blowing off northern Africa (the Sahara Desert to be precise, in case the name didn’t give that away ;-)) and usually inhibits storm development. <End Rather Obvious Jargon Alert!>

(What a match! I am now writing from the floor, having fallen off the edge of my seat part way through the third set. ;-))

Here is an image of the SAL (red stuff) and our little blobette (gray clouds) on the southern edge (near 40W):

Murray just took the lead 5-4 in the third set! Murray’s serve (hopefully this is the last point, recorded here for posterity)… 15-love… 30-love… 40-love, championship point!!!!!... aaagh, 40-15… second championship point… aaagh, 40-30… come on Murray!... doh! Out… deuce…sigh. Oh noes, in the net!! Who put that net there anyway? Aaagh. Advantage Djokovic… phew, back to deuce… oh NOOO just over the net!! Advantage Djokovic again. How can this stress be good for our hearts?!? Yes!… nice shot. Back to deuce. Oh WHAT! Ok, I admit that was a good just-over-the-net shot by Djokovic… advantage to him. Again. Sigh. Yes!… nicely played Murray! Back to deuce. (I’m not going to have any fingernails left if this carries on!). YES YES… advantage Murray!!! Championship point number 4… HE WON!!!!!!!! <breathe> !!!!!!!!!!!!!!!!!!. WOW! 77 years!! Amazing. I'd like to take the week off to celebrate (along with everyone else in the UK)... do you think anyone will notice? ;-)

Guess I’ll be back for the blobette tomorrow. Time for some celebratory somethings or other! J J

J.

p.s. nice interviews, including the one by Novak Djokovic.  

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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