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Well, I wrote today in my short Weather Journal update about how we are probably about to get our first widespread rain in months not related to a tropical system. But lo and behold -- the National Hurricane Center is noting today that the developing system is showing some tropical characteristics and that a hurricane hunter aircraft will be sent to investigate. The major difference between a tropical system and a non-tropical low is where it's drawing its energy. A tropical system draws it's energy from the evaporation of very warm ocean water; a non-tropical system forms because of the juxtaposition of unlike air masses. A tropical system has a tight, warm inner core; a non-tropical low has a broader area of circulation, and is generally cooler. And then there are hybrid systems, showing characteristics of both, called "subtropical" systems. And then there are tropical systems that convert to non-tropical systems, called "extratropical" systems. This one may well pass through any or all of those categories. It still looks like a potent rainmaker for much of our region, especially along and east of the Blue Ridge, as a strong easterly to northeasterly fetch of wind draws abundant moisture off the Atlantic. So it's possible the system could become a tropical depression or even a tropical storm named Kyle or Laura (depending on whether it or the system just northeast of Hispaniola develops first), but either way it looks like a windy rainmaker for the East Coast west to the Appalachians Thursday and Friday. The setup reminds me a little bit of Tropical Storm Tammy back in October 2005. It too was sort of a hybrid storm on the borderline between tropical and non-tropical, hurling a shield of rain westward as it spun off the coast of the Carolinas. I remember that one well because it soaked Virginia for 3 days before my wedding, finally relenting just two hours before the ceremony.