Tropical Storm Florence update 071900L
September 7, 2006
There’s not much terribly new to say about Florence. She’s continued to move to the west-northwest and is now roughly 1000 miles southeast of Bermuda.
Despite recent difficulties against the usual culprits of shear and dry air the intensity forecast isn’t much different from that of a couple of days ago. Florence is forecast to be a hurricane by Friday evening with further intensification thereafter to near category three status.
The most interesting thing about Florence is her large size. The very broad circulation covers about 12° of longitude; nearly 700 nautical miles. A pain for the forecasters over the past few days has been trying to determine an exact center. Ordinary visual and infrared satellite imagery has not been particularly helpful in this task as it’ll show one or more vortices spining inside the circulation only to die out later. The three agencies tasked with providing position estimates to the National Hurricane Center have tended to pick different vortices to call “the center” and as such, there have been substantial discrepencies in their position estimates, which in turn affects their intensity estimates, (which had gotten as high as 63 mph they’ve since gone down a notch). Tomorrow afternoon the hurricane hunter will be making its first flight to Florence to give more definitive answers to these questions.
Florence has been moving a little bit slower than forecast. As such the storm should enter the gap in the mid-Atlantic ridge sooner than previously expected. As such, it appears the only land mass seriously under the gun is Bermuda, with the Canadian maritimes possibly being affected later. Owing to the very large size of Florence, it’s about a given that Bermuda will feel some effects, but due to the small size of Bermuda, it remains highly unclear whether Bermuda would get the worst. The National Hurricane Center apparently views the forecast as straight forward; the normally loquacious Stacy Stewart’s 11 AM forecast discussion was a mere two (brief) paragraphs long.