Tropical Storm Danny: August 19, Update A

Just enough time to squeeze in a quick update before my next flight! :-)

I see Tropical Storm Danny-boy is churning away out there...He is currently at around 12N, 42W, with a central pressure of 1000mb and winds of 5ph:

He is currently at around 12N, 42W, with a central pressure of 1000mb and winds of 50mph.

First, his circulation... there is still a good vorticity signal in the lower half of the troposphere, with a small signal in the upper troposphere. This means that the storm still has pretty good circulation. 

Second, his convection... he is skirting the southern edge of that Saharan Air Layer I mentioned yesterday (the red and yellow area in the map below): 

which means that he is running into dry, dusty air and so his convection is still not as strong as it would have been otherwise for a storm with his circulation... BUT, sea surface water temperatures are over 27 deg C, with the upper 50-75m warmer than 26 deg C, so he does have enough from the ocean to sustain him. 

Second, in addition to the SAL, he is also bumping into a that high pressure I mentioned yesterday. This is why he has slowed and is now moving at 10mph (generally WNW). This means that the track is a little harder for me to predict, but the NHC has been generally good at the track from 1-2 days out last year, so I will go with this (for the next couple of days) - for the track part only, not the intensity!:

I would say that everyone, including the folks in Bermuda should keep an eye on Danny. I think there is a chance that he will move north of this track by Sat/Sun - but it depends on how that high pressure acts. 

That's the basics. Must run!

Ciao for now,

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 Depression 4: August 18, Update A

The last few weeks I have no travel and nothing is going on in the Atlantic (although the Pacific has been on a roll!)... today I travel, today we have a storm. Harrumph. Typical!

So, a very quick note. There is a storm in the Atlantic. End of quick note. ;-)

This blob is centered at 10.6N, 36.5W, and is heading generally westward at 13mph:

Central pressure is 1009mb, and winds are estimated to be 35mph. 

So... want the groovy news or the not-so-groovy news first? Let's start with the not-so-groovy and end on a high note shall we? 

The sea surface water temperature is around 28 deg C, with the upper ~75m of the water column being warmer than 26 deg C. This is warm enough to sustain a storm and allow it to grow. 

Looking at it's circulation, the vorticity is quite strong in the lower half of the troposphere, but there is also a very small signal in the upper troposphere. This means that the structure of the storm is good (for now) and if there was nothing working against it, it would continue to grow to a hurricane.

The groovy news is that there is something that is inhibiting it from growing at the moment... it is currently moving into a dense area of dusty, dry air from the Sahara Desert (cleverly named the 'Saharan Air Layer'), which you can see by the red areas on this map of the Atlantic:

This is acting to suppress the convection (rain, thunderstorms, and all that jazz), as you can see in this infra-red satellite video:

The red area, depicting really strong thunderstorms, has decreased and we are left with areas of yellow and orange, depicting heavy rain.

The pressure maps are showing that it will continue westward. It is a bit early to tell as this is still 3-4 days away from the Caribbean, but it may stay to the south. We'll see. 

Once they name it, this is Tropical Storm Danny. (I think it should already be called Tropical Storm Danny). 

I will check in again tomorrow, but a bit later in the day. 
Toodles my friends!
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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Post-Tropical Storm Little Claudette and Not-so-Little Pluto: July 14, Update A

As expected, Little Claudette didn’t last through the day today. She is now only slightly larger than Pluto (the PLANET) as seen from your home. Winds are currently at 45mph, central pressure is 1004mb, but although she has some circulation she is really part of a front, not a storm. The NHC are done with Claudette, and so am I. The next one is D for Danny-boy, who will be followed by elegant Erika.

But I’m not quite done with this post though! Being a cool and obviously trendy sciency sort of geek, I can’t leave without an honorary mention for New Horizons and Pluto today! Here it is (just in case you somehow missed it), taken with the LORRI and Ralph instruments on the spacecraft …  

(complete with a 'heart'). And here is a really nice video of images taken over the last week that NASA put together…http://www.nasa.gov/mission_pages/newhorizons/main/index.html

New Horizons took over 9 years to get to Pluto, about 3 billion miles away. It will continue to transmit data back, but is now continuing its journey away from the Solar System, and into the Kuiper Belt (which consists of icy 'objects' - or as Sharon H. says, UBOs - Unidentified Belted Objects - I expect it looks and probably feels a bit like the asteroid belt*) and on to er… new horizons actually! :-)

Eeek... and a real close up of Pluto shows even more details of the surface! 

(from R. Paul Wilson via K. Grazier). ;-)

I think it’s definitely time to raise (another) glass to NASA and the New Horizons team!

Ciao for now,

J.

*Due to a geek-a-luscious conversation with Trent F. I had to modify my initial description of the Kuiper Belt to the slightly more accurate version above. :-) 

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.
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Tropical Storm 'Little Claudette': July 13, Update A

I missed short-lived Tropical Storm Bob (I was probably having a 10-minute power nap at the time), and almost missed our pretty pathetic ‘Tropical Storm’ Claudette too! This is not what I would call a robust tropical storm by any stretch of the imagination. She officially came into being less than 12 hours ago, at 37.4N, 68.1W (quite a bit north of the ‘tropics’). She did try and have some convection, but is not doing so well at the moment. You can see a few drops of rain to the northeast of her center of circulation in the latest infrared satellite images: 

She does have some circulation in the lower half of the troposphere, so I would agree that she’s a tropical storm in structure. She is now at around 38.9N, 64.9W. Maximum winds are estimated to be 50mph, central pressure is estimated to be 1004 mb. 

She is moving over fairly cold water for a storm – the sea surface temperature is around 25 deg C. As she is moving to the ENE at a very rapid 20mph (too fast for any self-respecting decent storm), I agree with the NHC that she will soon decrease in intensity as she continues to move over colder waters.

There’s not much else to say about Little Claudette really. Obviously not much to worry about unless you are a fish. Or sailing in the middle of the north Atlantic.

More excitingly… are you following the exciting adventures of New Horizons and its 9 year journey to boldly go where no cartoon has gone before? Tomorrow is the day we get to Pluto! What an achievement for science and engineering and all such good things! Most definitely worthy of a celebratory glass or two! :-)

More tomorrow!

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.
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June 1: Start of the 2015 Atlantic Hurricane Season

Here we are again! Welcome to the official start of the 2015 Atlantic Hurricane Season and my witty background commentary (it’s like Mystery Science Theater 3000, only worse). ;-) I hope your off-season was filled with merriment, cups of tea, an ice-cream a day (to keep the Doctor away), and some exceedingly healthy wine and cheese… speaking of which, have you got your supplies ready?

As this is the official ‘Start of the season’, here are my top ten notes about this blog so you know what you are getting into for the season (remember, you can always watch reality TV if you are bored, or, for even more entertainment, I’ve found sitting in LA rush-hour traffic can be a barrel of laughs):

1. These updates are about fun, forecasting, and education... and tropical storms (and whatever else pops into my head that may, with some imagination and possibly after a glass or two of wine, fit those three words). It is just what I think.

2. I have a British sense of humoUr... you have been warned.

3. This is my hobby - sometimes you'll get one update a day, sometime four. If you are really lucky, you won't get any. If you wish to pay me to write, let me know and I'll send out updates as frequently as you like.

4. I hope you like Monty Python, Eddie Izzard, and The IT Crowd. And other funny stuff.

5. If you have any questions (preferably about tropical storms), please do not hesitate to ask. I will be happy to make up the answers for you. I can also cut and paste from previous entries (I’m very talented) so if I say something or use some "scientific jargon" (ooh ahh, how thrilling), please ask me about it.

6. I often write tongue-in-cheek, which sometimes hurts my cheek but what can you do? Gentle sarcasm, irony, and puns are all acceptable forms of communication. Unfortunately they don't always translate in writing so please don't be offended - like Planet Earth, I'm "Mostly Harmless" (Douglas Adams). Have a piece of chocolate or a drink instead.

7. I'm sure every cloud in the Atlantic is exciting to some but, unless I'm bored, I'll usually write about those that I think have a chance of developing.

8. Despite what you may have heard, I am not always right. But then neither is anyone else. Forecasting is complicated. Sometimes the crystal ball gets smudges and you are all out of Windex to clean it and the store is closed. So PLEASE pay attention to the National Hurricane Center, National Weather Service and your Emergency Managers - especially when a storm is looming because they have the most up-to-date information!!

9. I have stopped adding people to the listserve, so if you are still on that I highly recommend subscribing to the website posts (http://jyotikastorms.blogspot.com). It’s much prettier. I am working towards transitioning to the website only format anyway… as a part of my top-secret grand plan to take over the world (bwa haa haa - evil laughter in case you were wondering).

10. I confess, I am a twit. I am on twitter (@jyovianstorm). Twitter is cool. Just like bow-ties are (still) cool. (Dr. Who). I will post these updates on Twitter, but I’ll also tweet about storms in other basins so if you want to catch up between updates, that’s the place to lurk.

Still here? Great! Now, what about this season?

Mother Nature woke up a little earlier than usual this year with Tropical Storm Ana (because she was bored). I heard about some of the damage and chaos that TS Ana caused when she made landfall in the Carolinas… there was a broken blade of grass, I think an iris stalk got twisted, and someone had to use an umbrella as they sat outside reading their Sunday morning paper. J

The next named storm will be Bill (the name of my former boss. Hmm. That could be fun. ;-)).

So, what else do we have in store this year? The Grand Oracles of the Seasonal Forecast have given us their predictions:

Tropical Storm Risk (prediction date: 27 May): 10 named storms, 4 hurricanes, 1 major hurricanes.

Colorado State University/Gray-Klotzbach (prediction date: 9 April): 7 named storms, 3 hurricanes, 1 major hurricanes.

UK Met Office (prediction date: 21 May): 9 (+/-2) named storms, 5 (+/-2) hurricanes.

NOAA (prediction date: 27 May): 6-11 named storms, 3-6 hurricanes, 0-2 major hurricanes.

Everyone is opting for a below-average season, which seems reasonable given that the temperatures in the Atlantic are cooler than normal for this time of year. The average season (based on all storms from 1950-2014) has 11 named storms, with 6 hurricanes, and 3 major hurricanes (category 3 or higher). If you want to look at the average over the last 10 years (2005 -2014), which were (officially) slightly busier, the numbers are 15 named storms, with 7 hurricanes, and 3 major hurricanes. It’s interesting to note that even though the number of storms increased over the past few years, the average number of major hurricanes has not changed.

Of course, it only takes one storm to make the season a toughie. The most famous case was Hurricane Andrew in August 1992. The first storm of the season, and one of only 7 named storms, was a cat 5 hit on Miami!

For now though, all is quiet on the Atlantic front. Meanwhile, in the eastern Pacific we are on the 2^nd named storm of the season already. I’ll be back when there is something to chit chat about … maybe in November? ;-)

Ciao for now!
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 Ana: May 9, Update A

It’s a weekend… so of course there’s a storm out there! (isn’t that how these things work?) ;-) Well this is a relatively short update because I’ve got to go and watch the next Avenger’s movie in a couple of hours (which was sold out in LA last weekend!). J

Little miss Subtropical Storm Ana is now cute little Tropical Storm Ana – she made the transition overnight. She is currently centered at 32.7N, 78W and is no finally no longer stationary! She is crawling along at 3mph in a NW direction. Although the official winds are higher than yesterday, at 60mph, making her a mid-size TS (TS range: 39-73mph), the central pressure remains at 1001 mb.

Looking at the buoys in the water out there, the strongest winds I see are around 35 mph, so this official 60mph may be a slight overestimate.

In the grand scheme of things she is not very big. You can see that in this IR satellite image of Ana and the rest of the eastern and central US:

The convection in Ana is less than the stuff (technical jargon of course ;-)) in the front at the moment. That front is moving eastward, the leading edge of which is just about reaching western Georgia and the Carolinas. Once that front gets to Ana, it will whisk her off to the north and east. She’s on track to make landfall in the Carolinas tomorrow:

Her interaction with the front will determine exactly where in the Carolinas, but that overall cone is about right.

Although sea surface temperatures are not too toasty, she is crossing the Gulf Stream which is why she has that burst of convection (orange/yellow in the IR satellite image). Once she crosses that and gets closer to the coast, that convection should decrease.

She may have made landfall by the time I can check in tomorrow… I’ll be in Hawaii to prepare for the final competition trials of the Wendy Schmidt Ocean Health XPRIZE, where 5 finalists will be tested down to 3000m depths (for more details: http://oceanhealth.xprize.org/teams).

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.
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Subtropical Storm Ana: May 8, Update A

Well here we go again! JDearie me, this is a bit early to come out of hibernation isn’t it? Three weeks before the season is supposed to begin. I haven’t even had my morning cuppa tea yet! What was Mother Nature thinking? Yawn (ok, who else yawns when you read ‘Yawn’? ;-)).

Little miss Subtropical Storm Ana is out there, swirling away at 31.5N, 77.3W, currently with a central pressure of 1001mb and winds of 45mph, which makes her a weak tropical storm (TS range: 39-73mph).  Although she looks like a fierce little thing in the visible satellite movie:

Her bark is worse than her bite because she doesn’t have a lot of convection, as you can see in the infrared (IR) satellite movie:

I’ll explain satellite images properly later (once I’ve woken up J), but basically the convection is all to the south and east of the storm at the moment and the yellow/orange areas are the areas where it’s actually raining (with some heavy rainfall and possibly thundery weather in the orange).

She is stationary at the moment, and the NHC forecast track shows landfall in the Carolinas on Sunday:

I think this is reasonable. There is a high pressure system in front of her which is why she is stationary at the moment.

By the way, she’s called a subtropical storm because she’s essentially a hybrid - the circulation (vorticity) in the lower half has the characteristics of a tropical storm and the upper half of her is like a low pressure front. We often see these early and late in the season, when fronts are still rolling through. It looks like she is continuing to evolve though, and may eventually just be a tropical storm. And in case you are worried that this early storm is unusual or it’s a harbinger of a tough season ahead…abide by the words on the cover of the Hitchhikers Guide to the Galaxy and “Don’t Panic!” ;-)

<Science Alert!> Ooh… first one of the year! Oh lucky day! J It’s not unheard of to have storms this early and especially storms that pop up so close to the coast, but the good news is that they are generally dinky little things that usually bring that much needed rain. Here is a figure that I made a few years ago that shows the track of all storms from 1851 to 2005, divided into the month they formed/existed (graph credit: MOI!).

In the early and latter parts of the season we have storms that develop in the western Atlantic/Gulf of Mexico/Caribbean region. But early in the season things are still warming up and because they are so close to land, they don’t usually have time to develop. During the peak months it’s another story! Storms develop in the eastern Atlantic and have lots of space and time (but no TARDIS, thankfully!) to get nice and strong before getting to land. This figure also shows why we have a ‘hurricane season’. 97% of all storms form between June 1 and Nov 30, with 78% forming during the peak months of Aug-Sept-Oct (stats from Landsea’s 1993 paper). But you can see that every so often we do get storms that develop outside of the season (including January!). Not common, but definitely not impossible! <End Science Alert!>

I’ll send out another update later or tomorrow – after a civilized cup of tea. J

Toodle pip!
J.

p.s. Just a marker for my own reference… thanks to the ~6000 hits on the website since my last post in November, the current count is 88, 406!

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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November 30: Last Day of the 2014 Atlantic Hurricane Season!

Phew! What a busy season this was... boy am I glad it's over! :-) Now I can relax for 6 months and paint my nails, eat bon-bons, drink wine, surf the internet for cute baby animal photos, do some science-y things, help run a multi-million $ international competition, save the world, become a movie Producer and make a science fiction film... you know, the usual off-season stuff ;-)

More about that last bit later. First, let the 2014 Atlantic Hurricane Season Grand Reckoning begin! Officially we had a whopping 8 named storms this year, of which 6 were hurricanes and 2 were major.

I think the final tally should have been 7 named storms, 4 Hurricanes, with 1 major Hurricane. Tropical Storm Dolly was in existence for less than a day and remained extremely weak in early September. Hurricane Bertha was pretty wishy-washy and Hurricane Cristobel was a bit wibbly-wobbly. And although Hurricane Edouard snuck in as the first major hurricane of 2014 when I wasn't looking, he barely reached that strength for a couple of hours and then fell apart extremely rapidly.

Again, by an amazing coincidence, and for at least the second year in recent memory, the number of storms that were officially named matches the minimum number of storms that NOAA predicted would be named! Their forecast at the start of the season called for 8-13 named storms (leaving quite a lot of wiggle room there). Hmm. Don't you love coincidences? ;-)

My final hurricane comment this year: In this age of satellites and on-line information, everyone can see what is going on if they know what to look for. (It's so much fun! :-)) Now if the forecast was simply for a below-average year and there weren't any numbers of storms etc., perhaps one (and other ones that one knows) wouldn't question the motives behind some of these storm forecasts.

And that's it for this lovely, sleepy little season! :-)

As usual, I need to wrap with my annual award-breaking thank you speech. :-) I'd like to thank Doug M. at CMS/USF (www.marine.usf.edu) in Florida for help with the listserv and to Chris H. in Georgia and Ben A. for help with the website. I'd also like to thank the NHC for their hard work and for giving me something to rant about. Keep up the good work folks! ;-) 

I want to thank YOU! Still the best and most intelligent readers ever. :-) Thank you for reading and for sending me jokes, photos, on the ground reports, comments, and questions. Thanks for telling your friends about my fabulously hilarious, witty, informative, accurate, and entertaining writings. The blog website currently has 82, 366 hits... that's 10, 016 hits since the start of this season in which I only had 28 updates (my quietest season so far)!! :-)

Last, but definitely not least (especially because they know where I live and work!)... I also thank my family and friends for keeping me supplied with wine, cheese and other such essentials of life and for their continued futile attempts to keep me sane. ;-) I really want to thank my husband, Ben Alpi, for coming up with a new caper to keep me out of mischief during this quiet season, so now... I am the Producer (!!) of his next short film, a science fiction called Hashtag! (starring Gigi Edgley of Farscape & Jim Henson's Creature Shop Challenge fame):

 

It's a Twilight-Zone type story about our cultural obsession with social media and celebrity. If you want to find out more about this, you can look it up on http://runicfilms.com/hashtag (just FYI, 4 days until the Kickstarter ends ;-)). So that's what I'll be doing to 'relax' in my 'spare' time during the off-season! 

I'll continue to tweet, like any good twit (@Jyovianstorm) - about weather, the oceans, XPRIZE, science and science fiction, and of course, my new Hollywood life! Please feel free to follow along!

Until next season... I wish you all a very safe and happy holiday and non-hurricane season filled with much joy and merriment and good TV. Have a wonderful and Happy New Year! ;-)  

Toodle Pip!
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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Former Tropical Storm Hanna: October 27, Update A

Dinky little Tropical Storm Hanna-Barbera was out there today, singing Yabba-dabba-do! If you blinked at all in the last 12 hours (which, chances are, you probably did), you may have missed her. She 'formed', made landfall in the Nicaragua/Honduras region, and dissipated all in about 12 hours - a busy day for anyone!

Her winds were a mere 40mph. Tropical Storm winds begin at 39mph. Hmm. There was also very little (almost none) circulation in the mid-troposphere:

All-in-all, it seems a bit unlikely to me that she was a fully fledged Flintstone... I think she falls more into the category of one of those fake Jetsons.

So that was Hanna. Another name down and just over one month until the official end to the season.

A quick recap on the end of Hurricane Gonzalo: he did cause a bit of havoc on Bermuda but from what I hear, things are recovering. Just getting around to wrapping that one up... it's been a busy time over this way (you know what it's like leading a Hollywood lifestyle and all that ;-)).

Actually, I did want to end this entry with a farewell to my 18.5 year old kitty cat who has spent many hours keeping me company as I wrote this blog (ok, he was usually asleep but that's pretty much the effect I have on all company anyway ;-)). It was a sad week and we'll miss the little fella. So to all of you with four legged friends, give them a pat on the head from moi! Thanks little Tig!

More when the next one rolls around! The next name on the old list is Isaias.

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.
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Hurricane Gonzalo: October 17, Update A

I can see clearly now the rain has gone, it's gonna be a bright bright sunshiny day (J. Nash)... Hurray! Bermuda, that little pink dot in the middle of the Atlantic, is just about emerging after a day of Gonzalo's rain and windy weather.

I heard from Steve on Bermuda about 7 hours ago, who said it was a storm, and windy outside. He doesn't recommend going out in a hurricane by the way.

Circulation remained strong throughout the troposphere, so Gonzalo was/is definitely a hurricane. The question is what was the intensity.

I checked in on the winds at the island airport throughout the day and the highest sustained winds I saw were 93mph, which would make Gonzalo a strong cat 1 storm (Cat 1 range: 74-95mph). The strongest observed winds when the edge of the eye made landfall (at around 8.30pm local time) were around 76mph, again indicating a cat 1 storm. The NHC had estimated winds of 110mph, which would put him as a strong cat 2 storm (cat 2 range: 96-110mph).

Although he had an eye in the IR satellite and radar images, it wasn't clear in the visible satellite images (this was pulled earlier in the day) as there were clouds covering the eye, which further supports that reasoning that this was a cat 1 storm:

We'll find out tomorrow how Bermuda faired. I thought I'd keep this update brief... for now, it's definitely wine-o-clock!

More 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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Hurricane Gonzalo: October 16, Update A

Dear Bermuda, I hope you are ready for whatever tomorrow brings! I hope it brings some clouds, a bit of rain, maybe a strong breeze and short thunderstorm or two, some super high surf, and not much more.

I (and I'm sure you) have been watching Gonzalo the live long day and following, with avid interest, the advisories and forecasts from the NHC so you would have seen that for most of today they had Gonzalo as a cat 4 storm with winds of 145mph. They have now brought him down to 140mph, 943mb - he's still officially a cat 4 storm (cat 4 range: 130-155mph) and the NHC forecast that he'll remain a cat 4 for the next 24 hours (until Saturday night).

I agree that he was looking like a stronger storm today, and he may have been a strong cat 3/weak cat 4 (probably not quite with 145mph winds). He had good outflow in the satellite images, there was a pretty nice and strong eye for most of the day, and wind shear had clearly decreased because clouds weren't streaming off willy nilly. Even the lower level convergence(LLC)/upper level divergence (ULD) that I mentioned a couple of days ago looked better. To show you what the difference is in LLC/ULD between a weak hurricane (my opinion 2 days ago) and a stronger one, I have some figures to show you (from the U. Wisconsin):

Lower level convergence two days ago (when the NHC had him as a cat 3 and I thought he was weaker):

 

Low lever convergence today (NHC say cat 4, I more-or-less agree):

There are more/tighter concentric rings today, which is what you would expect with a stronger storm.

 

Upper level divergence two days ago: 

 

Upper level divergence today: 

As I said, I'm not sure he was as strong as 145mph winds would suggest, but I suspect the reason they kept him at that level was to spur you guys on Bermuda to get ready!

At the last advisory he was at 28.6N, 67.3W, heading NNE at 15mph. The eye looks like it will pass pretty much over/slightly west of Bermuda tomorrow evening:

Having said all that, there are some interesting things in the latest IR satellite loop:

I said yesterday that he would weaken as he got to 30 deg N because the warmer waters underneath the surface of the ocean become shallower around that location. The eye he had all day started to fracture when the 'real' outer bands reached around that latitude, and it looks like the convection is taking a bit of a hit from the lack of deep warm water. The sea surface temperatures are around 28-30deg C, so definitely warm enough to sustain him. The wind shear is still low, but it looks like he'll head into an area of slightly stronger shear tomorrow afternoon.

Here is the image on a larger north Atlantic map:

I wish I could stay awake long enough to see what happens to the center when it reaches around 30 deg N... maybe I'll wake up at 3am to have a quick peek! If that trend continues, Bermuda (located at ~32N) may not get hit by a major hurricane at least. Fingers crossed! (because that's how science works... ;-)).

Regardless, be prepared for something worse and pay attention to your Emergency Managers. And remember: run from the water, hide from the wind!

Stay safe!
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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Hurricane Gonzalo: October 15, Update A

No time for a cup of tea and a nice chat when one has a few words to say. Starting with... would you like to see a Hurricane that is intensifying from a cat 3 to a cat 4 storm? Here's one:

 

See how that eye became clearer? Oh and how about that increase in convective activity(more reds and grays)? Nope? Ok, how about that beautiful outflow pattern one sees with major hurricanes? Still nada? Hmm. How odd, I don't see any of those things either. I would normally rant a bit here, but too much to cover, so I'll just say I can't believe the NHC thought this storm went from 125mph winds (cat 3) to 130mph winds (cat 4)! This barely had a murky eye! They have been a bit off on the intensity of this storm all along, but this really took the biscuit!

Gonzalo is currently at 25N, 68.7W, heading N at 9mph. He slowed down as expected and I do agree with the NHC in their track forecast for the next couple of days:

Bermuda is going to get some dark and stormy weather alright, alas. He is heading north but is due to be swept to the NNE and then northeast by a front (the same one that caused some topsy turvey weather in the US a few days ago). You can see Gonzalo relative to the front in this IR satellite image of the Atlantic:

If you squint (or have a few drinkies), the front looks like a cricket bat about to hit the ball (storm).

His winds are now 125mph, central pressure of 953mb, which makes him a strong cat 3 storm (cat 3 range: 111-130mph). Finally, I think the NHC updates are coming more into alignment with what he actually is. They did (obviously) back down from yesterday's forecast which called for 140mph winds today! The forecast says he will remain as a cat 3 for a few days and then decrease in intensity.

I think that he now looks like a proper cat 3 storm for the first time in his little history:

There is a strong, clear eye, and the convection is also stronger (more red with a hint of grey), although not really strong enough to be a cat 4! He also doesn't quite have the classic outflow, but we do see a fairly good and clear vorticity signal in the upper troposphere at last:

The reason why I think he has intensified (from what was obviously not a cat 3 to a cat 3) is that the wind shear has decreased, and looks like it will continue to decrease, and he is going over a patch of very toasty sea surface temperatures (29-31 deg C). He should start moving away from such very warm temperatures tomorrow, but the water will still be warm enough to sustain him. The upper 50-75m of the water column are currently warmer than 26 deg C, but by the time he reaches 30N (still south of Bermuda) that should be limited to the upper 25-50m and we should start to see some weakening (still a storm though).

In short... I hope you are ready Bermuda. Even if he does decrease in intensity, I know it is really tough having a second hit in a week! I'll be watching tomorrow and may tweet updates.

Good luck and stay safe!
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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Hurricane Gonzalo: October 14, Update A

Very little time for sloth and idleness these days!

Mr. Gonzalo is looking healthy these days, isn't he? He is officially a strong cat 3 storm with winds of 125mph, central pressure 954mb. He is heading NW at 13mph and is centered at 22.2N, 66.6W (hmm, interesting... 666... generally not considered the most happy-go-lucky number but I guess he's ready for Halloween).

He is definitely stronger than a cat 1 storm as the eye is pretty consistently there! But he's not the best looking storm I've seen, and he is a little ragged for a cat 3 storm. At the most, I'd give him a cat 2 status.

Why? Well I'm so glad you asked...

1. The convection is rather weak for a cat 3 storm. The infrared satellite image shows none of those gray areas that show us that the clouds are really high and there is a lot of very deep convection,

2. There is very good vorticity (circulation) in the lower half of the troposphere, but the vorticity (circulation) structure is just not there at the highest level of the troposphere:

In the <Science Alert!> reminder link I had yesterday, you can see what the upper (200mb) of the troposphere vorticity should look like for a strong hurricane - it should be a stand-alone round(ish) 'splodge' (technical term ;-)), not an area of higher vorticity that stretches across a large area - those are troughs!

3. There is wind shear, which is clearly impacting this storm as the cloud pattern is not circular. You can see in the satellite image that they stretch off to the northeast.

4.There is remarkably little upper level divergence and relatively little lower level convergence. Oooh... what the heck is she talking about now, I hear you say. Time for a New <Science Alert!> (how exciting!) A tropical storm has low pressure in the center, near the surface. That's why we all keep mentioning the central pressure - the lower it is, the stronger the winds (usually). A low pressure is an area that the air is 'pulled' towards. By extending that image to a circular storm, you can imagine the winds are pulled in from all around - i.e., they converge. So we have Low Level Convergence. Now the problem is that if you keep pulling winds in at the low levels, they have to go somewhere. It might come as a surprise to you, but they don't just gather around the center and have a game of poker. ;-) The ground (or sea) is underneath, so the only way the air can go is up. And when the air reaches the top of the storm the only way the winds can flow is out and away from the center. So at the top we have Upper Level Divergence. The stronger the convergence/divergence of a storm, the better the formed it is. Ta-da. <End Science Alert!> Phew. Time for a little lip-wine-convergence now I think.

I could go on with my list,
but you get the gist.
 (Poetry at last! A rival for William McGonagall? ;-))

The official forecast says that Gonzalo will become a cat 4 storm with winds of 140mph within 12 hours. Officially it might, but I expect there to be actual evidence of this in 3 out of 4 of the above in that case! In reality, it seems unlikely to get quite that strong at the moment. Although sea surface temperatures are 28-29 deg C, Gonzalo is moving to an area where waters warmer than 26 deg C can be found in the upper 50-75m compared to the current 75-100m. Wind shear looks like it will continue for a bit too (at least into tomorrow).

Popping back to St. Thomas for a moment. Tom (on the ground there) said that although the NHC said the storm would be strong,"there was not a puff of wind all of last night" and so they "Slept well with no wind or rain pounding on roof".

Looking ahead, it does look like Gonzalo has shifted a bit to the west and may not be a direct hit on Bermuda now. It also looks like he may shift a bit more to the west than the current trajectory shows and he will slow down a bit (which is already shown to some extent in the track for tomorrow).

Unfortunately for you Bermudians, this means you will be hanging out on the wrong side of the tracks (insert 'as usual' jokes here)! As you can see, most of the convective activity is on the east side so get ready! I'm probably right (as I generally like to use The Force), but I'm going to give the NHC the benefit of advanced technology and say that this may be a stronger disturbance than nature is indicating. Best listen to the local folks as you make your preparations.

Speaking of local people to listen to, Steve B., from Bermuda, certainly hasn't been asleep at the wheel (fortunately for everyone on that island) and is obviously already preparing as he says in a note I got earlier today: "We could be in for a sticky weekend. I doubt if much cricket will be played! I had better fortify myself!". Words of wisdom. Spot on! :-)

That's it for this evening. More from me and Mr. Gonzalo (and anyone from Bermuda who wants to pipe up) tomorrow,
Night night!
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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Hurricane Gonzalo: October 13, Update A

So I woke up this morning and was a little miffed to see that this system was still considered to officially be a weak Tropical Storm with winds of 45mph:

Luckily for us (and the people that were already under/in the path of this storm!), hurricane hunter planes have been in the system all day and returned data to say that the storm was stronger than the official word/forecast. What would we do without them?! The NHC have been steadily increasing the intensity to hurricane strength over the past day and it now has winds of 85mph, central pressure of 984mb.

I'm not surprised with this increase in intensity. He already looked a little stronger than 45mph when I wrote last, and as I said then, the only thing that would keep Gonzalo from getting out of order would be his interactions with the islands - everything else was in favour (with a 'u' ;-)) of a little more intensification. Throughout the day I had a look at the vorticity maps (ok, I know it's been months since you read about these - not my fault it's been a gloriously quiet season :-) - see here for the <Science Alert!> on Vorticity Maps: http://jyotikastorms.blogspot.com/2014/08/hurricane-bertha-august-4-update-a.html). He has really good circulation in the lower half of the troposphere, and some circulation in the upper troposphere - enough to be a cat 1 hurricane, but no more. It looks like he is heading into an area of stronger wind shear, so even though the water temperatures are warm, I would not expect him to get much stronger than a cat 1 storm.

He is currently centered at 18.7N, 63.4W, heading NW at a regal 12mph. He passed just north of St. Maarten and his eye went directly over the island of Anguilla. He has quite a lot of convection - rain and thundery weather:

I heard from my great on-the-ground reporter, Tom on St. Thomas throughout the day (thank you for the updates Tom!!), who said they needed the rain and started the day expecting the storm to pass directly over them. It passed to their east, however they did lose power for a few hours. It's back (last I heard... and he needed a well earned drink! ;-)).

Once Gonzalo clears the islands, it looks like it's heading for Bermuda, which obviously needs another storm a week after a direct hit from the last one!

I have a pretty strong sneaky suspicion (ooh, alliteration!) that this track will shift to the west. But of course, Bermuda better get ready and stock up on the barrels of rum just in case.

 

Now a quick word about Fay... she fizzled out over the Atlantic. Done. Counting fishes would tire anyone!

 

That's all for today folks.

Night night!
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.
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