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
-------------------------------
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
-------------------------------
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
-------------------------------
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
-------------------------------
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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Wednesday, October 15, 2014

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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Tuesday, October 14, 2014

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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Sunday, October 12, 2014

Hurricane Fay and Tropical Storm Gonzalo: October 12, Update A

A travel day today (sitting in San Francisco Airport as I write this) so I'll jump right into the thick of things... and I have to say, there are a few thick things about! We have a veritable smorgasbord of storms today as in the last ~24 hours three, yes three, storms made landfall (and one overachieving storm decided to make landfall twice)!

In the western Pacific, Typhoon Vongfong made landfall in Okinawa as a cat 3 and then moved on to make landfall on the island of Kyushu in southern Japan as a weak cat 3. Last week this storm was out there in the Pacific as a cat 5 storm with winds of 160mph. It has caused quite a bit of havoc as it's moved along.

In the Indian Ocean, Cyclone Hudhud made landfall in eastern India as a strong cat 3 storm. About 400,000 people were evacuated ahead of this storm in an effort to save loss of life.

Meanwhile, in the Atlantic, Tropical Storm Fay passed directly over Bermuda. She was still a strong Tropical Storm at the time, not a Hurricane, but they got quite a lot of strong thundery weather. She has since moved away and it looks like Bermuda may have re-opened for business.
 
I agree with the NHC on their analysis of this one in that she will not be a hurricane for long (currently she is a weak hurricane with winds of 75mph, central pressure 986mb). She is heading into the Atlantic to hang out with the cute fishies for a while:

That leaves one of the Atlantic Blobs from yesterday, which is now the very weak Tropical Storm Gonzalo with official winds of 45mph, central pressure 1002mb. He is centered at 16.4N, 59.7W and is heading west at 10mph. He does have some circulation, which you can see in the visible satellite image:

But the convective action is not yet fully developed as we see in the infrared satellite images:
However, this one will definitely develop. I think he may be a little stronger than 45mph at the moment, but not by much. Wind shear is pretty weak and looks like it will remain weak. The sea surface temperatures are currently between 28-30 deg C, and it looks like they will increase to 29-31 deg C closer to the Leeward Islands. Water warmer than 26 deg C can be found in the upper 100-125m of water, which means he has lots of stuff (technical term ;-)) to fuel him.

His current forecast trajectory takes him through the northeast corner of the Caribbean as a Tropical Storm on Monday and Tuesday.
The only reason he won't intensify too quickly is because he is going to be interacting with the islands soon. He should bring some rain - you guys want rain, right?

I've gotta run and catch my flight (it's a long walk from SF to LA!), but more tomorrow!
Tally ho!
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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Saturday, October 11, 2014

Tropical Storm Fay and the Atlantic Blobs: October 11, Update A

Oh tropical storms, how I have missed you! ;-) I know, I know, I've been incommunicado for a month and missed the last two storms but I was rather super busy (I'll tell you what shenanigans I was up to later) and luckily they weren't too much of a bother. Actually, you may have missed Dolly yourself as she was a named storm for about 3 seconds on Sept 2, reaching max. wind speeds of 50mph (a nice breeze). I'm not sure she should have been named. TS Edouard was named on Sept. 11, and although he was a proper storm (reaching hurricane strength with official max winds of  115mph on Sept. 16th, making him the first major hurricane of the season), he remained a gentleman and stayed in the Atlantic.

And now we have Fay and the Atlantic Blobs (please note: this is not a band from the 50s! ;-)).

Currently Tropical Storm Fay has winds of 70mph, central pressure of 990mb, and is therefore a very strong Tropical Storm (TS range: 39-73mph). She is definitely a storm and this intensity seems reasonable given how much circulation and convection she has:



The bulk of the convection (which includes some severe thunderstorms because the infrared satellite image is red) is on the western side of the center which indicates that she is experiencing a lot of wind shear. The sea surface water temperatures are 27 deg C, so warm enough to keep her going.
That little pink 'dash' close to 32N, 65W is the lovely Bermuda. Although Fay is officially centered at 25.9N, 65.4W, heading N at 18mph, from the visible satellite image it looks like the center may be a bit west of that location, at 25.9N, 65.9W. The forecast track has her curving to the NE and passing just south of Bermuda, which is why the location of the center is important...

If the center is west of the current location, there is a small chance that the center will pass to the west of Bermuda, which would be better for Bermuda because most of those thunderstorms will also pass to the west. If the center does stay in that current cone of uncertainty or if the center actually goes over Bermuda (quite possible), then the weather will be a bit crummy for Bermuda tonight and over the next day or so. Hopefully everyone has dusted the cobwebs out of their wellies and canceled the golf games!

There are a couple of Atlantic blobs out there as well:
Both are still in the 'Whoa, where are we?' stage of development. I'll talk about them tomorrow methinks. For today, it's all about Bermuda and, obviously, that means it is time for a Dark & Stormy! :-)

Before I pop off and partake of above mentioned beverage, the reason why I wasn't around in September was because I was at the Monterey Bay Aquarium Research Institute, testing competition Entries for the $2 million Wendy Schmidt Ocean Health XPRIZE! (oceanhealth.xprize.org). We have 18 Entries from 6 countries competing for this prize and the goal is to develop accurate, robust and affordable pH sensors to help detect and understand ocean acidification. I have to say I've learned that there's never a dull moment being part of a competition! :-)

Until tomorrow,
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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Thursday, August 28, 2014

Hurricane Cristobel: August 28, Update A

I've arrived on this other planet called 'DragonCon', along with the Klingons, Wolverines, Daleks, Harry Potters and Hermiones, a gaggle of Superheroes, and a collective of other beings. So entertaining. Of course I'm Storm... who else would I be? ;-)

I see Cristobel is still officially a Hurricane with winds of 80mph, central pressure 973mb. I'd agree with this wind speed as he was trying to develop a little eye a few hours ago (not very clear though), so that would be around 90mph:

However his convection is relatively weak for such a storm, with very few strong thunderstorms and it looks like it is falling apart a bit. This is because his top is really part of that front that we've seen all week:

He's trying to be helpful and avoid most landmasses except one... (bwaa haa haa) 

Bardarbunga watch out! I see the B-movie title already... Hurricano! ;-) (copyright: Me!)

He is currently at 38.5N, 61.5W heading ENE at 36mph.  That superfast forward speed is another sure sign that he is caught up in a front, which is carrying him to the northeast.

I may not be on here tomorrow unless the other little 'disturbances' do something silly, but I don't think much is going on with Cristobel.

If you are at DragonCon, just a reminder that I'll be giving a talk on the wonderful stuff that goes on at XPRIZE at 5.30pm tomorrow, and right after that I'll be on a disasterlicious panel at 7pm on "A Practical Guide to the End of the World!" (panel will also contain a geohazards expert - earthquakes, volcanoes and the likes; a nuclear astrophysicist - solar flares, meteors etc; a biologist - sharks, dinosaurs etc; and an infectious diseases physician - plagues, ebola etc.- I think between us we have it pretty much covered! :-)).

Toodle pip until Saturday!
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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Wednesday, August 27, 2014

Hurricane Cristobal: August 26, Update A

Oh how the days do fly by when you are having fun! I have to pack to go to another planet (disguised as a city called Atlanta) tomorrow, where there will be weird and wonderful alien beings. :-) Who else is going? Let me know! I'm giving a talk on Friday at 5.30pm on XPRIZE. Then at 7pm I'll be on a panel: A Practical Guide to the End of the World. Should be a barrel of laughs. Stop by and say hello! :-) :-)

Meanwhile, today, back here on planet Earth, Hurricane Cristobal is still a fairly weak cat 1 and officially has 80mph winds (cat 1 range: 74-95mph) and a central pressure of 983mb. Although official he is at 30.4N, 71.5W, heading N at 15mph, from the satellite images it looks like he is closer to 30N, 72W - a bit south and west of the official location.

Earlier today the NHC wrote: "Cristobal's cloud pattern is not typical of a hurricane on IR images. The convection is quite linear and the system appears to be embedded within the tail of a frontal zone.". Yes, thank you very much.

Since then, Cristobal tried to regain his manly identity as a Hurricane (or really a Tropical Storm) in the lower levels of the troposphere, even though he is still somewhat stuck in that front in the middle and upper levels (vorticity at 500mb - the middle of the troposphere shows that he is not an isolated 'blob'):

They did increase his wind speed slightly to 80mph, but it looks like he is having a few issues now...

Even though he still has some circulation (more than he had as a 'hurricane' yesterday) and you can see that familiar banding structure, that strong convection (red bit - lots of thundery weather) in his center just went puff in the space of about 7 hours!

There are a handful of reasons why his convection would fall apart so beautifully:
1. Sea surface temperature. Unlikely to be the cause because although he is over slightly cooler waters, with temperatures in the 27-29 deg range, it is still warm enough to keep him going.
2. Dry air. There is some dry air to his west, which does begin to get pulled into the system as it weakens, but this doesn't appear to be the initial cause:

3. Very shallow layer of warm water underneath: I think a bigger factor in his decline is that he has just moved from an area where the upper 75m of the water column was warmer than 26 deg C, to an area where only the upper 25m is warmer than 26 deg C. So as he churns away, he is mixing up water that is colder than 26 deg C, and about 26.5 deg C is the water temperature you need to really sustain a tropical storm.

I am not sure he will remain like this though. Given that he is stuck in that front, I think the convection will return (at least to some extent) as he moves north and goes over the Gulf Stream, a warm strong ocean current that runs along the eastern coast of the US and then heads east, out into the Atlantic around 35N. The upper ~50-75m of the water column in the Gulf Stream is warmer than 26 deg C.

As you can see, Bermuda, that little blip in the Atlantic, is under some cloud cover - probably a perfect day for a BBQ and refreshing beverage. ;-) (What do you mean you can't see it?!?). It does look like his center (should he survive) will pass to the west of Bermuda, but the cloudy goodness is on his east, so, well, you can obviously expect beautiful sunsets for a few days (behind the cloud cover).

Right, must dash and pack! I'll try and hop on tomorrow, but I may be sucked into a space/time vortex. I'll be back as soon as I emerge - sometime in the future.

In honour of ...
 
Nanoo nanoo, and a good day to you!
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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Tuesday, August 26, 2014

Hurricane Cristobal: August 25, Update A

An eminent geologist gave me the low-down on what happened in Iceland with Bardarbunga ... "Actually the Icelanders turned the volcano off using big underground magma valves. They decided that they can create more havoc and thus hold the airline industry for a larger  ransom at a later time. Hey, you gotta do what you gotta do to enhance your GDP." (Source shall remain anonymous to protect his Great Geologicalness). 

Regarding the other natural havoc in the Atlantic arena... not much time for dilly dallying tonight, alas, as I have a bit of ranting to get done.

So Cristobal is a Hurricane, hey? Officially his wind speed is 75mph, which makes him barely a cat 1 (cat 1 range: 74-95mph), central pressure is 989mb. He is located at 25.1N, 71.9W, heading NNE at 2mph. He has barely moved from the poor Turks and Caicos, who are well and truly drenched at this point I imagine!

I'm not sure I quite agree with this analysis of him being a hurricane. <Rant Alert!> Ok, truth be told, I really don't agree with this. You can't go around naming storms hurricane willy-nilly just because you measured some high wind speeds! In that case a winter gale or a tornado should be named a hurricane because it has high wind speeds. It's just not on. Cristobal is more of a front meeting a Tropical Storm rather than a full out Hurricane. Sigh. <End Rant Alert!>

Let's look at the evidence...

1. There is a lot of convection, I give them that. You can see this in the infrared satellite video:


But you would expect a lot of convection with any stormy weather over water temperatures in the 29-30 deg C. It looks more like a blob than a well-organized tropical system.

Even the NHC admit: "this system's cloud pattern does not resemble that of a hurricane, with little or no evidence of banding on satellite images." No banding. No eye. Nothing.

Of course, you could say that the long line of very active thunderstorms and rain showers streaming off to the northwest (over Bermuda) is because of wind shear. It does look like wind shear. But is it just wind shear or is something else afoot (aloft)?

2. We can look at the structure of the atmosphere to find out, and we do that by looking at the vorticity fields....

These show a long line of higher vorticity (greater circulation) stretching across the Atlantic in a SW-NE direction at all levels of the troposphere. This is the signal of a front.

Lower level of troposphere (850mb):

Middle troposphere (500mb):

Upper troposphere (200mb):

By comparison, Hurricane Marie off to the left, has the well-organized circular structure of a Hurricane. Looks very different, doesn't she?

So, the circulation is not showing the structure of a Hurricane, and the convection is not showing a Hurricane. And therefore... why would one call this a Hurricane?!? It should still be a Tropical Storm as there is a signal of one still in the lower half of the troposphere, even it if is getting a bit entangled. If I was cynical, I might even say that this is one of those 'we need the numbers' things. But luckily for you, I'm young and carefree and not cynical or skeptical or any of those other words ending in 'ical' at all, so I won't say that. Not At All.

All this silliness aside, what does it mean for you Bermudians? It looks like you're going to get a spot of rain (it looks like you may already have had some?). Although the track has Cristobal passing to your west on Weds, I would still dust off the galoshes and stock up on the tea, wine and ice cream (good advice for most situations I think ;-)). The NHC have generally been rather good on the track at 1 day (even if their intensity estimates are poor), but Cristobal is caught up with that front and is a bit bulky, so although the center may not pass over you, you might still get a bit of a breeze. I would be ready also in case the track does shift a bit more to the east - I'm not ruling that out yet.

More tomorrow. Must run... mudpie ice cream is melting... ;-)

Toodles 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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Monday, August 25, 2014

Tropical Storm Cristobal: August 24, Update A

Mother Nature pulled a fast one in Iceland yesterday! Today the scientists over yonder said that there was no sign of a sub-glacial eruption at Bardarbunga after all and something else is afoot (my leading theory is that the rumblings are caused by an alien spaceship. Obviously. ;-)). Hmm... maybe this volcano-eruption malarkey is just a ploy to make us all learn another Icealandic word?

On the other hand, a magnitude 6.0 earthquake hit the Napa region of California!! Aaagh! The WINE!!(Warning: following image may be disturbing):
(image credit: D. Duncan, via C. Kellogg)

Quelle horror!

Breathe. Breathe. Ok, I'm back...

So... at least the storms are behaving in a somewhat predictable manner. The blob in the Atlantic turned into a weak Tropical Storm Cristobal today. (Historical Note, thanks to Mr. Locke: Cristobal Colon (minus accent aigu) was the real name (in Spanish) of Christopher Columbus. His REAL real name is Cristoforo Colombo since he was Italian; however he discovered the Americas on Spanish ships so Cristobal Colon is it.)

Cristobal's winds are officially at 50mph (TS range: 39-74 mph), central pressure is 996mb. Here are the vorticity maps so we can see his circulation (and hence, structure) in the troposphere. There's something really cool in these maps... not only is there a poorly defined Tropical Storm in the Atlantic, but you get the rare privilege of seeing the structure of a cat 5 hurricane in the Pacific!

Near the surface (850mb):
 
In the middle troposphere (500mb):
 
 
In the upper troposphere (200mb):

He is barely a Tropical Storm because the vorticity is not an isolated blob, but is connected to low pressure to the north and south (like a front) - this is an indication that he is not very well-organized. Another indication that he is only a Tropical Storm at the most is that there is no blob in the upper troposphere (you only see that in hurricanes). In comparison, in the Pacific just southwest of Mexico you can see the vorticiy signal for Hurricane Marie (lower left quadrant) - she is a cat 5 storm with winds of 160mph! The circulation is so strong (the force is strong with this one ;-)), that it is white in the lower and mid troposphere, and almost white in the upper troposphere. That, my friends, is the vorticity (circulation) signal of a pretty darn-tootin strong storm!

Because he is so poorly defined, the NHC estimate Cristobal's center to be at 24.5N, 72.9W and he is stationary at the moment. He was drifting slowly to the north earlier today. It looks like the pressure fields have changed since yesterday and are opening up a path for him to move northward and stay out in the Atlantic, away from the US. He is stationary at the moment because he is bumping up against high pressure (it's like climbing uphill for him), but it looks like he should move northwards tomorrow and then to the northeast.

He does have a fair bit of rain in him... I think the Turks and Caicos are getting a bit of a washing!
This is because the sea surface water temperature is a very warm 29-30 deg C, with the upper 50-100m warmer than 26 deg C. That's enough to keep him happily fed for now.

And for those who asked... I thought the new Dr. Who was ok. Not a strong an opening episode as a couple of other Doctors as it was a bit heavy handed on the differences between this Doctor and the previous one and it was a bit chaotic. I'm not sure I like all the opening sequence changes yet either. I am also curious to see how going back to a more avuncular Doctor plays out with the new audiences. I, for one, enjoyed the old Dr. Who, and don't mind at all. :-)

More tomorrow!
Ciao,
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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Saturday, August 23, 2014

Tropical Depression 4 and Volcano Special: August 23, Update A

A big day today! The much anticipated new season of Dr. Who begins with a new Doctor! :-) How exciting! Oh yeah, and that rather big volcano in Iceland erupted today.

I suppose it's time to dust off the ash from my last Volcano Special a few years ago but first there's a little Blob that's been crossing the Atlantic, now in the vicinity of the Turks and Caicos. He's a dinky little thing with winds officially at 35mph (central pressure 1005mb).

I agree with the NHC that he is just a Tropical Depression at the moment. The vorticity fields for the Atlantic show that he has some circulation in the lower half of the troposphere, but it is not very well defined yet. (I know, it's been weeks since we talked about vorticity! If you need a refresher on how to read these, check out the Science Alert in this very intelligently written blog: http://jyotikastorms.blogspot.com/2014/08/hurricane-bertha-august-4-update-a.html ;-)). Also, in looking at the satellite images, he doesn't have much structure or much convection. Pretty wishy washy... for now.


He is currently centered at 22.0N, 72.4W, heading NW at 11mph. The forecast track and intensity calls for him to become a Tropical Storm as he goes over the Bahamas tomorrow and on Monday, and then a Hurricane on Tuesday as he curves to the N and NE and remains in the Atlantic. Although the forecast track keeps him away from Florida and the US coast, I am not so sure of this yet. I think there is a possibility that his track will shift to the west. Once he reaches 39mph wind speed, we will meet TS Cristobal (which, in case you were confused, is actually a male name... the internet tells me it is 8 times more common to be a boys name than a girls). More tomorrow on this Blob!

Volcano Special
And now for something completely different! Iceland has decided it wanted some attention so it has gone and set off another volcano. ;-) Alas, this one is much larger than Eyjafjallajokull that brought air traffic to a halt in Europe for some time in 2010. But don't worry, there is a bright silver lining to this volcanic eruption... it is much easier to pronounce. Bardarbunga (minus some accents and whatnots over a few letters here and there) is pronounced BAUR-DAR-BUNG-KA, as demonstrated in this little video by some nice Icelandic chap: https://www.youtube.com/watch?v=413V0bmjvBg.

Now, just in case you are silly enough to be contemplating air travel that involves Europe or the Atlantic anytime soon, I thought you'd like to know where to look for potential forecasts and find out Bardarbunga's latest shenanigans. (Bardarbunga really does sound like a muppet name, doesn't it? :-)).

To read about what the volcano is doing, I go directly to the Icelandic Met Office: http://en.vedur.is/earthquakes-and-volcanism/articles/nr/2947. This is a pretty good site and scientists who have been monitoring the volcano will update it with a report a couple of times a day.

<Forecasting Alert!> For volcanic ash forecasting the world is divided into regions with a Volcanic Ash Advisory Centre (or Center ;-); VAAC) per region:
Each VAAC is responsible for providing the official global forecast for ash from any misbehaving volcano in it's region (see website below) so that all aircraft are using the same information and there is no confusion (a good thing to avoid, especially if you are in a plane!). The London VAAC covers Iceland and is based in the UK Met Office: http://www.metoffice.gov.uk/aviation/vaac/vaacuk.html. Should there be a need for advisories, this is the place to look. I'll write another update to let you know what's what if we need to use that page. <End Forecasting Alert!>

Now it's time for Dr. Who!! Woohoo! I have my cuppa tea and Double Decker ready for the viewing. :-)

More tomorrow!
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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