Saturday, May 09, 2015

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
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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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Friday, May 08, 2015

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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Sunday, November 30, 2014

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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Tuesday, October 28, 2014

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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Saturday, October 18, 2014

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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Friday, October 17, 2014

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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Thursday, October 16, 2014

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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