Saturday, May 26, 2012

Subtropical Storm Beryl: May 26, Update A

Must be quick for now… I have a ‘J.S. marries J. S.’ wedding to attend! J

Here’s the scoop on Subtropical Storm Beryl. She has slowed down to a halt, which was expected given that she is surrounded by high pressure and is currently hanging out at 31.6N, 76.3W.  Officially the winds are still 45mph and central pressure is 1001mb, but they are sending in a plane to check on this. The wind shear is very weak now. Her circulation in the lower half of the troposphere* (*See Science Alert below) continues to strengthen, so I think she may be a bit stronger. However, she has very little convection (rain and clouds) so I can see why they kept her at 45 mph. There are two reasons for this the lack of rain: (1) from the ocean perspective, she is over cold water with nothing warm to get much moisture from; and, (2) from the atmospheric perspective, she is pulling in dry air which is coming from the south and west.

Her track is a little tricky still because she has stalled. The NHC did move it slightly north since my last update, but have shifted it back towards Jacksonville, FL. I will go with this for now, but I would still get ready for a breezy day in NE Florida and Georgia tomorrow and Monday! Her intensity is the part I’m not sure I agree with at the moment. To get to land she still has to cross the Gulf Stream. Unless she picks up speed and zooms across it, the chances are she will get a bit stronger. The NHC continue to forecast a peak of 50mph winds, which means she’ll be a very weak Tropical Storm (TS range: 39-73mph) at landfall. This is fine with me… so long as they don’t give us any of that ‘rapid intensification just before landfall what a surprise’ stuff. Given that she doesn’t have much moisture today, even if she gets stronger, I no longer think she’ll get to hurricane strength.

What a topsy turvy sort of start to the season! I haven’t even said ‘ello properly and I’m already launching into jargon… hopefully I haven’t lost everyone already. So, the first <Science Alert> of 2012! <Science Alert> For those who need a refresher, don’t know, or just want a chuckle… I keep mentioning “troposphere”. This is the lowest section of the earth’s atmosphere. It extends up from the surface to about 8-10km at the poles, and to about 16km at the equator. In this section, the higher you go, the colder the air temperature gets. The next section of the atmosphere above the troposphere is called the “stratosphere”, not to be confused with “The Stratosphere Hotel and Casino” in Las Vegas! Although like any casino in Vegas, the higher you get, the warmer it gets! J (unless you are very rich… and if, by chance, you are very rich and reading this, I have a great project you can sponsor…). Anyway, back to earth… you may have heard of the stratosphere as the home of the ‘ozone hole’ (and ozone layer of course). The stratosphere extends to about 50km above the surface of the earth. The boundary between the troposphere and stratosphere is called the tropopause. Most of our clouds are in the troposphere. However, with strong, fully fledged hurricanes and thunderstorms, the clouds can sometimes cross the tropopause and extend up into the stratosphere. Above the stratosphere is the mesosphere, where the temperature again gets colder the higher up you go. When I refer to the lower half of the troposphere, I am looking at from the surface to around 5-6km height. <End of Science Alert>

Ok… must go and party! I’ll still be watching out for Beryl to make her next move!

Cheers,

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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