Friday, August 06, 2010

TS Colin and the Atlantic Blobette: August 6, Update B

TS Colin:
Poor Colin... he's barely a Tropical Storm actually - although circulation is good, there is hardly any convection. Come on Colin, if you want to be a Tropical Storm with conviction, you gotta have convection! I got a note (or three) from Steve B. in Bermuda, who said it had started to get breezy about 5 hours ago... surfs up! ;-) It looks like he (Colin, not Steve) will pass to the east of Bermuda. Even if the eye goes directly over it, what little convection there is will be to the east.
Currently he's at 28.3N, 66.6W (!), and moving N at 9mph. Central pressure is estimated to be 1009mb.
Satellite Imagery:
If you would like to see him swirling and twirling away in the Atlantic for yourself you can look at satellite images or movies. Go to the NHC site: and scroll down to where it says 'Atlantic Views'. Under that it says 'GOES-East', and under that it says 'Atlantic Wide Views' or 'Western Atlantic' or 'Caribbean' etc. Under any of these, you can pick an image or a movie (Java or Flash). Visible gives you the visible image in black and white, so at night it's not as clear as during the day. Water Vapor (at the bottom of each list) gives you water vapor. The other one I use most frequently is IR AVN (2nd one down on the list), which is the infrared image with colours added on. These colours represent how high the clouds reach into the atmosphere because they are based on the temperature at the top of the cloud. It gets colder the higher you get in the troposphere, so we can tell from cloud top temperature how strong the convection is. The red colours are very big high clouds with the coldest temperatures (other than a dark gray), and blues and whites are lower, warmer clouds. These generally correspond to how much convection is occuring - the redder the cloud colour, the more active the convection. My general rule of thumb (having seen these images and lived under them at the same time) is that blue and yellow areas are mostly clouds, with some rain in the yellow areas. But as you get to the orange and red, you get thunderstorms and possible tornadoes (in the red/dark gray areas).
For Colin, I suggest looking at the Western Atlantic set of images. There is also usually a close up of a system that is of interest. These are near the top of this page and are labelled Atlantic Floater 1 (Colin), 2 etc.
Once you have a movie open, there are a series of tabs at the top. You can play with those, but they include things like latitude/longitude grids, sea surface temperature, and the forecast track of the storm. At the bottom is the time the image was taken. Have a play! Then you can follow other storms as they develop. How fun is that? You, too, could spend entire evenings sitting at home watching satellite image movies of storms developing. Just like me. Er... I mean I do other fun things too...really... ;-)
The Atlantic Blobette:
Looking at the Atlantic Wide imagery, you can see this 'little' blobette is still way out there in the Atlantic - somewhere around the 30-40W range, between 10-20N. If you look at the IR AVN images you will notice that although there are a lot of clouds at the moment there aren't many that are yellow, orange or red... they are mostly blue and white, which means it's just cloudy with not a lot of rain or thunderstorms. There's some low level circulation, but it's slap bang in the middle of a massive layer of dust blowing off the Sahara, which is drying out the atmosphere and inhibiting convection. I'll keep an eye on this because 'tis the season (ho ho ho), but for now it's just a bunch of clouds (with very little rain) and not a lot of convection.
That's it from me on the storm front for today. But to change the subject with absolutely no segueway whatsoever, Will L. sent me this amusing article from The Irish Times about tourism. It made me chuckle, so I thought it might make you chuckle too...
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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 was there and was going to "run away, run away" (Monty Python), I'll let you know.


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