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Posted at 05:00 PM ET, 08/16/2009

Tropics Spring to Life: Claudette Nears Fl. Landfall

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By Dr. Greg Postel, Tropical Weather Expert

After weeks of inaction, tropical activity in the Atlantic and Gulf of Mexico has abruptly blossomed, almost as if someone hit a switch. Three storms have formed in the last two days: Ana, Bill, and Claudette -- though Ana was just downgraded to a depression.

The one closest to home, over the northeastern Gulf of Mexico, is tropical storm Claudette (max winds 50 mph as of Sunday afternoon). Claudette presents a modestly benign appearance in the data. Looking more like a mid-latitude system, with an asymmetric comma-shaped cloud field, Claudette will probably evolve into a significant rain event more so than anything else.

Without much "room" to intensify, it's likely that Claudette will not strengthen significantly in the time it takes to reach the coast of the Florida panhandle tonight. Its close proximity to land should prevent the otherwise slightly favorable environment (reasonably light shear, humid surroundings, and warm sea surface temperatures) from allowing Claudette to evolve into a hurricane. The storm appears to be subtly associated with an upper trough in the westerlies over the Ohio Valley.

The southwesterly winds aloft over the northern Gulf of Mexico represent the southern tip of this mid=latitude trough. Though not strongly sheared, these winds are introducing a nontropical component to its development. Claudette will weaken once the core circulation crosses land, and ultimately unload high rainfall totals (probably in the 5-10 inch range along its path). Some of its moisture could make into the D.C area by the middle of the work week.

Check back tomorrow for updates on Ana and Bill...

About the author: Dr. Gregory Postel is the lead meteorologist for a weather-risk management firm in Overland Park, KS. He earned his Ph.D. in atmospheric sciences from the University of Wisconsin-Madison, and conducted research on factors leading to the development of tropical cyclones. He's an avid hurricane chaser and has been known to drive more than a thousand miles to intercept land-falling hurricanes.

By  |  05:00 PM ET, 08/16/2009

Categories:  Tropical Weather

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