Tuesday, June 04, 2013

Gulf of Mexico Blobette: June 4, Update A

I’ve been holding off on writing about the blobette in the Gulf for a couple of days because I wasn’t sure she would amount to much, but I think the time has come to say a few words. This is the little blobette that almost could, but then decided not to, and then changed her mind and thought she’d give it a go anyway, but may not get there after all. How's that for a 'few words'? ;-) She is a little confused, poor thing. Aww. But it’s completely understandable because she has conflicting influences – some pushing her in one direction, others holding her back.

She didn’t have much circulation to talk about until today really. This afternoon she started to drift away from the ‘calming’ influence of the Yucatan Peninsula and into the Gulf of Mexico, and since then her circulation has slowly started to improve.  But there is some good news. First, the circulation at the moment is in the lower half of the troposphere (ooh, how exciting… first <Science Alert> of the season! And there was much rejoicing! ;-)).

<Science Alert> The troposphere. Our atmosphere is divided into layers – like a trifle or seven-layer dip or lasagna (depending on what country you are from). Each layer has air temperature either increasing with height or decreasing with height. The troposphere is one of these layers. It is the lowest section of our atmosphere and extends up from the earth to about 15-16km in the equatorial regions, and to about 8km in the polar regions of the planet. All our 'weather' essentially occurs in the troposphere. It is defined by decreasing air temperature with increasing height. You would know this if you climbed a mountain. Or the easier option, of course, is to just look at pictures of mountains and see the snow at the top (known as the ‘Florida option’). J The top of the troposphere is called the tropopause. Strong tropical storms have clouds that reach as high as the tropopause - and in a few very strong cases, they can extend even higher into the next layer up. The layer of the atmosphere above the troposphere is called the stratosphere, which is defined by air temperature increasing with height. The ozone hole is in the stratosphere. <End Science Alert>

For our blobette, not only is the circulation in the lower half of the troposphere (which means a weaker storm), but there is also quite a bit of wind shear which is inhibiting her. You can see this in the satellite image:

The low-level circulation is just north of the Yucatan, but the clouds and rain are all to the east (southeast/northeast) of that area because of wind shear. (I’ll explain how to read satellite images properly in a later post… got to give you all something to come back for! ;-)). The other good thing in the atmosphere is that there is a lot of dry air over her center and to the west. This will really help in stemming her development.

From an oceanic point of view, we have a really good set up… it’s so good that I’m beside myself with glee and think this calls for a second glass of wine! ;-) Although the sea surface temperatures are around 27-28 deg C (a storm needs water warmer than 26.5 deg C to develop), the Loop Current <Science Alert> is pretty far south and doesn’t really extend far up into the Gulf at the moment! I know, you are wondering how this is enough of a reason for a second glass of wine… first, one doesn’t need a reason, and second, it’s very exciting for anyone who lives along the gulf coast. And look, it’s your lucky day… a second <Science Alert> in one entry. Let the rejoicing continue! J   

<Science Alert> The Loop Current. The Loop Current is part of an ocean current system that flows from the Caribbean into the Gulf of Mexico through the Yucatan Strait, and then out of the Gulf of Mexico through the Straits of Florida, and up the east coast of the US. How far it extends into the Gulf of Mexico varies from year to year and month to month. Last June it’s northernmost extent was around the same latitude as Tampa Bay (in Florida). This June however, it looks like it’s northernmost extent is about as far north as the Keys! As this current flows around Florida, it changes name to become the Florida Current. Then as it flows up the east coast, it changes name again and is known as the Gulf Stream. It leaves the US east coast around North Carolina and flows across the north Atlantic to the UK. Why is this current system important for tropical storms? This current system is well known because it has the deepest warm waters, and is very fast flowing. The deep warm waters mean that tropical storms that pass over any part of this current system have a jolly good (British understatement) chance of becoming stronger. <end Science Alert>

So, because the Loop Current is so far to the south, it looks like she may not interact with the deepest warm waters very much… which means she won’t develop as much! Now isn't that exciting? :-)

It doesn’t seem likely that she will amount to much, but I’ll be back tomorrow.

I’ll sign off with something that Ian H. forwarded: An 85 year old lady from Kentucky was asked what she would do differently if she could live her life again… she said she’d eat more ice cream. J I thoroughly approve and will do the same right now. J (“If I Had My Life To Live Over Again” by Nadine Stair: http://projectbebold.com/archives/807)

Cheerio!

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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