Rarety of Gaston-Like Storms?

General Questions
#1

This is a question for meteorology buffs – as you may be aware, the Carolinas are being assaulted today by Tropical Storm Gaston.

Hurricanes usually form in the Tropical Atlantic, off the Cape Verde Islands, in a rather broad area of extremely warm ocean. They regularly form in the Caribbean and the Gulf of Mexico, though those storms are failry uncommon.

But Gaston formed from a stationary low sitting in the Atlantic off the coast of Georgia and Florida, in the bight of sorts that the coastline forms there.

And that is something I’ve never heard of happening before.

I’m aware of the theoretic possibility of tropical storms forming anywhere the water temperature is 27.5 C or higher and a low begins to form – but is Gaston just a bit uncommon, a “normal rarety” in the sense that something like this is known to happen, but only once every 50 years or something, or truly odd – like a Force 6 tornado, it’s theoretically possible but so improbable as to be inconceivable – until it happens.

#2

That book by Jay Barnes on all of the hurricanes that have impacted NC showed more than a few that popped up right off of our shore line. From what I remember of the book, it’s not all that unusual. The Gulf Stream is right there so there is more than enough energy for storm formation. Hope someone else comes along with a better answer than this.

I’m in Chapel Hill. We don’t have anything but clouds as yet.

#3

hermine just “popped up” off the coast now. in '02 four named storms “popped up” off the coast; arthur, gustav, cristobal, and edouard.

the cape verde storms tend to be the most powerful when they hit land, ie the 1900 storm in galveston. they have a long time to gain strength and water on the way to the coast. a lot of them kinda wander about the atlantic and not hit the coast. hurricane alberto in '00 had a great time wandering around (19 days) and even did a loop-de-loop in the open atlantic.

#4

As others pointed out, it is not uncommon at all for tropical storms/hurricanes to develop in the Caribbean and the Gulf of Mexico. A little less common are those that develop right off the east coast. (BTW, I live in Charleston, SC, and the “eye” passed just to the north. Rained like the dickens all day, with strong winds. I use “eye” in quotes because Gaston was never a hurricane, reaching top steady winds of 70MPH. It did have a well developed center, and apparently an eye wall, so I don’t think it makes any difference whether the storm is a hurricane or not to develop an eye. Usually, an eye forms when the winds reach 74 MPH. End of parenthetical.)

In fact, in the early part of the hurricane season (which is from June 1 to November 30), most of these tropical cyclones develop in the Caribbean or GOM. It is only about now thru the end of the season when they arise off Africa. Tropical cyclones developing off the coast here is not that uncommon. As a matter of fact, Hermine has just developed off Bermuda, but this one is expected to follow Gaston up north.

#5

Actually, it formed 145 miles SE of Charleston, right off the SC coast, and it was giving us bands of showers all last week, before it became a tropical cyclone. We all feared that would happen, as even then it was spinning off bands of showers in a counterclockwise direction, as if it were a TS.