Tuesday, October 6, 2009

Tropical Storm Grace (2009)

Storm Active: October 4-5

On October 1, the center of a non-tropical low over the Azores developed a small area of showers. However, the showers didn't persist and no tropical cyclone formed. The low moved slowly northeast, hindered by a stationary front to its north into October 4. Then, an area of convection flared up rapidly within the low that evening, resulting in it being classified as Tropical Storm Grace. It formed at 41.2 N and 20.3 W, making it the farthest northeast a tropical cyclone has ever formed on record, Since the low was already fairly strong (995 millibars before Grace's formation) Grace already had reached a strong tropical storm intensity of 65 mph winds and a pressure of 990 millibars. Grace's movement quickened to 25 mph, as it went speeding off to the northeast. Despite being in a hostile area for tropical cyclone development, Grace strengthened into the morning of October 5, reaching its peak intensity of 70 mph winds and a pressure of 989 millibars. At its peak intensity, Grace was a very small system, less than 100 miles across. In comparison, the widely scattered shower activity of the extratropical low spanned hundreds or even a thousand miles. Throughout the day of October 5, Grace continued northeast, reaching a forward speed of 30 mph, and began to weaken. It was then absorbed by a frontal boundary late on October 5. The combined system caused scattered showers over the British Isles over the next day but no damage resulted.

Grace at its peak of a small, intense tropical storm in the extreme northeast Atlantic.

Grace's track.

No comments: