Wednesday, November 30, 2011

November 30: Final Day of the 2011 Atlantic Hurricane Season!

Welcome to the final entry of my award-breaking blog for this year!! J I might be leaping to conclusion, but as I sit here in subtropical Florida in my sweater, with the fire blazing merrily away, I’m inclined to think that the season is pretty much over. Yes my friends, it is that time of year when you can breathe a sigh of relief and thank your lucky stars (and have a glass or two of wine) that this is the last Hurricane Season message from me until next year. Probably.

(Unless, of course, that blobette with a 20% chance of development that the NHC are watching today does something silly. It has some circulation (but more like a front than a storm), not much convection, and very little conviction. It’s just Mother Nature’s wonderfully capricious sense of humour to have a blobette today, that’s all. ;-))

This year was actually a quieter season compared to last year and, contrary to some reports, I think it was generally an average year. Officially we had 19 tropical named storms, of which 7 became hurricanes and 3 were major hurricanes. As usual, you may have noticed that I didn’t always agree with the NHC (I was trying to be subtle, so I wouldn’t be surprised if it escaped your attention ;-)). According to the blurb: “This level of activity matched NOAA’s predictions and continues the trend of active hurricane seasons that began in 1995.” Hmm. Really? Let’s dissect this (because I’m a scientist and that’s what we all do in the movies).

The average season now has around 12-13 named storms, 6-7 hurricanes, and 2-3 major hurricanes. So we had an average number of hurricanes and major hurricanes. That leaves the number of named storms. We know there were some Micky Mouse storms (hey, I live in Florida, I have been indoctrinated ;-)) – those that would have been cartoon characters if they had a chance. They wouldn’t have been named in ye olde goldene dayse because our satellite data interpretation wasn’t as good. Definitely Tropical Storms Cindy, Franklin and Jose. TS Lee and TS Harvey were also rather questionable and rather short. So that leaves us with 14 storms (including subtropical Storms) that would really be eligible to attend the Queen’s Garden Party (provided they had the right hats). So I’ll go against the grain and say that really, in the grand scheme of things, this wasn’t greatly above average as seasons go. Ho hum.

And that, I think, will be my last scientific commentary for this season. Hurray! J Now it’s fun-time. First, some exciting statistics for this blog (well, it’s exciting to me J). This is my 100th entry for this season. This is also the conclusion of 5 years of having a proper website blog (which looks very blog-like with all the photos and whatnots), and 6 years of a listserve. During that time, the website has had around 21, 200 hits! That is amazing for something that has, generally, been spread by word-of-mouth. If I include the listserve since the beginning (c. 2005), you, your family, your friends, your friend’s friends, your families friends, your friends families, your family’s family, your cats, dogs, goldfish, ponies and sheep, and all their friends and families have, collectively, read my ramblings over 500,000 times!!! Gulp.

THANK YOU for continuing to read, for telling people, and for entertaining me throughout the season with jokes, comments, and fabulous questions. Also, a BIG Thank You to those of you who were in the paths of assorted storms who sent me your thoughts, comments, photos etc. That really livened up what would otherwise have been a very dull read. Thanks to the NHC for doing a pretty tricky job really, and for being Moriarty to my Sherlock (or possibly vice versa?)...give me a call if you need a hand. ;-) I also need to thank my fantastic technical support team: Doug M. at the CMS/USF (http://www.marine.usf.edu/) in Florida for helping me maintain the listserve, and Chris H. in Texas and Ben A. in California for helping me maintain and upgrade my website blog. By the way, if you want to take a dip in geek-nirvana and are interested in B-movies and other such things, Chris and another friend, Scott, have just re-booted their classic podcasts at http://stomptokyo.tumblr.com/. I also want to thank Andrew T. in North Carolina who contacted me via twitter to invite me to write my first guest blog entry this year for Southern Fried Science (http://www.southernfriedscience.com/). This is a groovy blog by marine science students in North Carolina. Unfortunately I completely goofed on this (sorry sorry!) because it was right around the time of Hurricane Irene and in the midst of an unusually mad travel/work schedule for me (my real job strikes again ;-)). Hopefully, next year? Finally, last but not least, I have to thank those who are in the thick of things – those who are near and dear to me. Thanks for your continued attempts to make me sane... you have a life-long project. Good luck with that. ;-)

Although I usually hibernate from now until June, I do have a couple of marshmallows on the fire… as you know, I’m a twit (JyovianStorm), and will continue to tweet about storms in other basins as well as other things that I find interesting (science, science fiction, literature, and things). AND now for something completely different (Monty Python)… I have a NEW blog! it’s a photo-blog called ‘Just around the next corner’ and can be found at http://jyovianstorm.tumblr.com/. I started this a couple of weeks ago (so I’m still a bit wonky on it) and am currently posting photos of the South West Coast Path walks in Devon, UK. Two new photos appear every day, and there are multiple pages now. Here is one sample:


“One of those rare cloudy days in the UK, just after the UFO took off…”.  

Click on them to see them in high-res. I’ll be posting other photos once I run out of these.    

Well I think that’s it from me for 2011!! So… here’s a big slurpy (and slurry) toast to the end of the Hurricane Season. I wish you all a very happy and safe holiday season, Happy New Year and all that jazz, and I’ll be back for the 2012 Atlantic Hurricane Season!

Cheers & TOODLE PIP!
J. 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, November 11, 2011

Extratropical Storm Sean: 11/11/11 Update A

Happy Elevenses Day (11/11/11), Veterans Day (US) and Remembrance Day (Commonwealth Countries)! Hands up if you did something to mark the 11/11/11 11:11:11 second?  (Me too ;-))

This will be my apopemptic entry on Sean (oooh aaah… big word alert – I learned it today so I had to share J). He is officially at 36.7N, 57.7W, heading ENE at a whopping 35mph. This fast forward speed is because he is now fully part of that low pressure front I mentioned yesterday and doesn’t have the circulation of a tropical storm; the vorticity (circulation) is no longer confined to a nice circular area in the lower troposphere. Winds are 40mph (so officially barely Tropical Storm level) and central pressure is estimated to be 1000mb. Not much more to say really.

For those of you taking advantage of a three day weekend to fix things around the house, here's something that I hope will help:



Enjoy! ;-)

Toodles!
J.

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

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DISCLAIMER: These remarks are just what I think/see regarding tropical storms - not the opinion of any organization I represent. If you are making an evacuation decision, please heed your local emergency management and the National Hurricane Center's official forecast and the National Weather Service announcements. This is not an official forecast. If I "run away, run away" (Monty Python), I'll let you know.
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Thursday, November 10, 2011

Tropical Storm Sean: November 10, Update A

I found two things of note today. First, I found a sharp metal shaving in a restaurant. I was there for lunch and it caught my attention after I realized it didn’t have quite the same consistency as the cooked pasta I was chewing. Oops. And second, I found that the NHC and I are in better agreement. Not oops. J

Tropical Storm Sean is currently at 31.5N, 68.2W moving ENE at a nice 13mph. He has remained a mid-to-high Tropical Storm with winds of 65mph and central pressure of 983mb. His convection has improved a bit, but the dry air is still a factor and the wind shear is pretty strong for him so the convection is all to the northeast (satellite IR image):



I think the NHC have dropped the idea of Hurricane Sean for this year – their forecast now keeps him as a Tropical Storm until tomorrow, when he merges with a low pressure front that’s moving eastward off the US (as you can probably tell if you live along the eastern US – it is certainly breezy and cooler in Florida this evening). I’ve heard people say that the windy weather in Florida and the choppy waters are because of the tropical storm… nope…. they are because of this front. You can see this front in the water vapor satellite image as the band of clouds that stretches from the northeast to the southwest and covers Florida:



It is a little tricky for me to see the center of circulation because he is not very well organized and it’s night now, but it looks like it might be slightly to the right of the forecast track, so it might pass a bit closer to Bermuda. It still looks like it’ll be more windy than thunderstorms over the island because the bulk of the heaviest convection is already almost due west of Bermuda.

I’ll be back tomorrow… assuming I didn’t actually swallow any metal - a bit of extra aluminium (note: correct UK spelling ;-)) or whatever it was is probably good for me anyway, right? And alcohol can be used to clean cuts can’t it? Hmm… ;-)

Adieu 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 Sean: November 9, Update A

Happy Carl Sagan Day! Ok, so by the time I finish this I know the day will be over and many of you won’t read this until tomorrow, but I was too busy celebrating by watching the last couple of episodes of the excellent series ‘Cosmos’ with some like-minded geeks. Yes, of course there was wine. ;-)

In keeping with the spirit of Dr. Sagan I should warn you that I may, perhaps, exhibit some very subtle signs of science and healthy skepticism in the next few minutes…

Tropical Storm Sean’s vital statistics currently show that he’s at 29.7N, 70.9W moving N at 8mph. The estimated central pressure is 991mb and winds are 65mph, making him a mid-to-strong Tropical Storm (range: 39-73mph).

I can’t believe the NHC think Sean may be a hurricane tomorrow! (did you notice my very subtle skepticism?). Didn’t we already cover this earlier in the season? I would not classify a storm as a hurricane if the upper tropospheric vorticity is actually a low pressure front! The structure is not the same as a tropical storm at all. Goodness me. Here are some reasons why he’s nowhere near being a hurricane:

1. The vorticity (circulation) is strong in the lowest half of the troposphere so it certainly looks like a nice Tropical Storm. However, the vorticity (circulation) from the mid-to-upper troposphere looks more like a low pressure front than a tropical storm… it is spread out over a  large area, from the northern Caribbean to Georgia. A tropical storm would have a confined area of vorticity.  

2. The convection continues to remain weak. Given that the blue areas are clouds with no rain, the light yellow is a light drizzle, and the orange areas are heavy rain with some thunder, does this IR satellite image look like it’s strong enough to be approaching hurricane strength?



He looks remarkably similar to yesterday’s image (which was similar to the day before). At the most, I would continue to place him as a mid-sized Tropical Storm.

3. If we look at the lower level convergence and upper level divergence (remember those from earlier in the season? – if not, send me a note and I’ll find my ‘should-be-award-winning-if-there-was-one-for-this’ fabulous explanation for you ;-)), we see that the lower level convergence is strong enough for a tropical storm, but the upper level divergence is really wishy-washy.

The biggest inhibitor continues to be the dry air. Wind shear dropped a little since yesterday, but it’s still enough so wind shear continues to have a bit of an effect on this storm.

Although I’m not buying the intensity thing, I think the track is generally good. He will pass to the west of Bermuda and shouldn’t  really affect any land too much. At the rate he is going, he’ll be passing Bermuda during the day tomorrow instead of overnight.

Before I go, I thought I’d mention that there was a big non-tropical storm in Alaska today. Chris in Washington DC thought I would be interested in knowing such a thing was happening (yes indeed! Thanks!). This is not a tropical storm of course, but it was big enough to evacuate people and create some NOAA storm quick-look pages, which are normally used during a tropical storm. The reason for the evacuations and the storm pages is because there is some rather large storm surge. Here are the National Ocean Service observations of this from the coastal water level instrument in Nome, Alaska (provided via tidesonline.nos.noaa.gov):



The top plot shows the water level. The blue line in the top figure is the usual predicted water level along the coast, the red line is the observed water level along the coast, and the green line is the difference between the two… i.e. the storm surge. You can see that the water levels along the coast at Nome were 10ft above normal, and the surge was 9ft!! That is HUGE. And that’s just from a ‘normal’ winter storm I think.  The second plot shows the winds, which went up to about 42 knots. The third plot shows the drop in pressure as the storm passed by… down to 970mb! That’s less than some tropical storms!  The last figure shows the air and water temperatures, in deg F… hmm, I see temperatures of 17 deg F, How toasty is that? Practially bikini-wearing weather, right? Ha. So not only was the storm surge high, but the water was cold (just over 32 deg F when the surge was the highest).

That’s it for today. Time for a lovely nap now. More tomorrow though!

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, November 08, 2011

Tropical Storm Sean: November 8, Update A

How does the time go by so quickly, huh? Anyway, very little of it is left today for me to write this so it’ll be quick and very practical and not very funny at all.

The NHC changed Sean to a Subtropical Storm in the early hours of this morning. That would be in keeping with the vorticity (circulation) signals I was seeing, where he looked like a Tropical Storm in the lower half of the troposphere, but had a low pressure front signal in the upper troposphere. I think they should have left him as a Subtropical Storm because he really only looks like a Tropical Storm in the lowest levels of the troposphere - the vorticity is looking more like a low pressure front now in the middle levels of the troposphere as well as the upper levels.

He is currently at around 27.5N, 70.5W. This is a bit south and west of the official location of 27.9N, 70.1W. He appears to be heading westwardish, officially at 3mph. Winds are 50mph, with a central pressure estimated to be 999mb, making him a low-to-mid level storm (TS range: 39-73mph).

As I expected, convection really has not picked up – the IR satellite image from this evening is here:


Can you spot the difference from yesterday’s IR image? Oh yes, there’s that one small cloud…  ;-) There is just too much dry air around him for the convection to pick up and I still don’t see this changing any time soon.

There are storm warnings for Bermuda. It should be a lovely breezy night on Thursday. I’m not sure you should even bother dusting off the umbrellas.

I had all these grand plans to write about people I know called Sean, asteroids, high storm surge where the water temps are 1 deg C (brrr), and other relevant stuff, but must sleep now. Tomorrow is Carl Sagan Day. Maybe that will inspire me to write something scientific and clever … ;-) (one can hope at least).

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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Monday, November 07, 2011

Atlantic Blob: November 7, Update A

In true Monty Python manner, the Atlantic Hurricane Season says, “I’m not dead yet!” J

There’s a swirly blob in the Atlantic centered at 69.7W, 27N, just southwest of Bermuda. The NHC have marked this as having a 70% chance of becoming a tropical depression. This looks like a tropical depression already to me. You can very nicely see the closed circulation if you look at the satellite images. Here's the latest IR image:


If you want to watch the video to see the swirliness, scroll down on this page: http://www.nhc.noaa.gov/satellite.shtml until you see the heading ‘Atlantic Floater 1’. Click on Visible – Flash or IR – Flash to see the moving pictures (ooh, pretty). Looks like some nice closed circulation, doesn’t it? The vorticity (circulation) is actually very strong in the lower half of the troposphere and has the signature look of a tropical system.  There is also considerable vorticity in the upper levels of the troposphere, but that is associated with a low pressure front.

There are two factors that are inhibiting this from developing. The IR satellite image shows very little convection which is because of the dry air around it, and the you can see the clouds streaming off to the north and east, which indicates wind shear.

It seems unlikely to me that this will develop very much more because of these two things, but it’s worth keeping an eye on just because the circulation is strong.

Ho hum. So much for an early nap! I’ll be back if this thinks of doing anything dodgy. The next name is Sean, in case we need to know such things.

Ciao!
J.

p.s. <Cool Astronomy!> As you know (or will know once you’ve read this), there’s a Large Asteroid in the ‘hood. It is the size of an aircraft carrier, or around 400m wide for those of us who haven’t got aircraft carrier sizes memorized. It will pass just slightly closer to Earth than the moon’s orbit. “Don’t Panic!” (HHGTTG). It is called ‘YU55’ (no relative of U2). The last time this sort of thing happened was in 1976, but the astronomers of the day forgot to set their alarms and didn’t know this had happened until it was too late. Having been caught snoozing once, they have already calculated the next time this will happen (other than tomorrow of course) will be in the year 2028. They have set their alarms for the year 2027 and 45 seconds… <end of Cool Astronomy!>

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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