I would wager that most people in the United States, outside of Floridians and serious storm chasers, do not know what a tropical wave is. A tropical wave is a weather system originating between the Tropic of Cancer and Tropic of Capricorn, characterized by low pressure, severe thunderstorms, and lots of wind. It is the predecessor of the tropical depression and tropical storm. In fact, the only thing that prevents a tropical wave from being called a tropical depression is that it either a) is not organized enough (doesn't spiral around a central point); b) doesn't have enough convection or c) doesn't have strong enough winds.
In the case of the tropical wave Tortola experienced last night, the only thing missing was organization. Sustained winds of 35 mph hit the island overnight, and 6" of rain fell on Tortola on 10/5/10. That doesn't include the rain that continued to fall after midnight this morning. The tropical wave we experienced, now tropical depression 17 and soon to be Tropical Storm Otto, brought far more rain to Tortola than Hurricane Earl did six weeks ago, and I believe, far more destruction as well.
I'm sure the folks in North Carolina, and all along the East Coast of the United States, are now conversant with the destruction that large quantities of water dumped on a small area in a short period of time can do. Over the weekend, they too, contended with a tropical wave, although the Weather Channel never called it that. The remnants of Tropical Storm Nicole, disorganized, and stretched over a huge north-south axis, brought similar conditions to the Carolinas and the Mid-Atlantic states.
I have not been out further than to walk the dogs this morning, but HB assures me the damage is significant. Having driven safely to work, without incident, the day after Hurricane Earl, HB did not hesitate to go into town this morning, but on the phone, he told me he several times tried to turn around to come home, because the roads were so torn up they were nearly impassable in the Hyundai.
I hope to get out of the house later this afternoon, once the rain has stopped, and get some pictures of the effects of tropical wave 97L. If I do, they'll be up here this evening.