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Title: A Magnificent Collapse (cyclone forming in gulf mysteriously disappears)
Source:
weather.com
URL Source: http://www.weather.com/blog/weather ... tml?from=wxcenter_news#reports
Published: Aug 21, 2006
Author: Stu Ostro, Senior Meteorologist
Post Date: 2006-08-21 14:04:51 by gengis gandhi
Keywords: None
Views: 149
Comments: 1
One of the most basic rules of forecasting tropical cyclone formation is to see if deep convection (rain clouds and thunderstorms) persists, because oftentimes what goes up comes down just as quickly. If there's a big blowup over water and it continues for at least 12-18 hours, and is collocated with a well-defined surface wind circulation & low pressure as well favorable conditions aloft, then development can ensue. A couple of days ago (Tuesday August 15) there was not only an example of a big burst of convection over warm water imploding after equally rapidly exploding, it was one of the more dramatic such instances one is ever going to see. Thunderstorms cranked up in a hurry in the morning; by early afternoon satellite imagery as well as buoy observations indicated there was low-level convergence with evidence of a surface low (where I placed a red "L" on the image), and convective elements were forming on the east side of the "center" in addition to the main area on the west. Later in the afternoon the main eruption sure was an eye-catching sight (above)! Then, fortunately, not only did the whole thing go kaput, by late evening the only evidence left on satellite imagery that anything ever existed was a narrow circular ring of harmless wispy clouds around the edge of what just few short hours before was a roiling mass of thunderstorms. A number of factors may have caused this to happen and the convection to not appreciably regenerate that night and yesterday. Tropical cyclones are sort of like tornadoes in the sense that the right instability and "dynamics" are necessary throughout the atmosphere for them to form (there are interesting differences in the specifics, such as wind shear overhead generally being favorable for severe thunderstorms and tornadoes and unfavorable for hurricane development -- however strong upper-level winds near tropical cyclones can be favorable by creating outflow jets.) Mercifully, more often than not all the ingredients don't come together perfectly, or there'd be a lot more hurricanes and tornadoes, and the disasters they bring. I think we have enough of them already! 
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#1. To: gengis gandhi (#0)
Lips that would kiss form prayers to broken stone.
not only did the whole thing go kaput, by late evening the only evidence left on satellite imagery that anything ever existed was a narrow circular ring of harmless wispy clouds around the edge of what just few short hours before was a roiling mass of thunderstorms.
Nobody's jugs are bigger than Annette's.
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