Tropical Storm Karen, expected to move toward Florida’s Panhandle today and bring us rain Monday, is a reminder: This is the season of the “Frankenstein storm.”

Karen formed from a wave of storms in the Caribbean Sea. It is, in other words, an outlier: not your usual storm. But there’s nothing unusual about it.

This has been an outlier of a hurricane season, one in which very little of the storm activity forecasters anticipated actually occurred. Almost astonishingly for a season predicted to be busy, no major hurricane has formed so far.

Other than Karen, “the next 10 to 14 days look quiet in the tropics. That continues the inactive theme for this year’s hurricane season,” said severe weather liaison Mark Malsick, with the S.C. Climate Office. But, as he cautioned, it’s too soon to call the season quits.

The worst threat for the Lowcountry is largely past: The opportunity is vanishing for powerful hurricanes to form coming off West Africa, the Cape Verde storms. Those are the biggest danger for the Southeast coast.

But a year ago in mid-October, a storm wave in the lower Caribbean roared into Sandy, the largest hurricane ever recorded in the Atlantic basin. Sandy would go on to kill 147 people, about half of them in the United States, and destroy an estimated $50 billion worth of buildings and other infrastructure.

There’s two things to remember about Sandy:

On Oct. 25 it was headed toward Charleston from the Bahamas with winds of 105 mph.

The storm was not a hurricane or even a tropical storm when it devastated the Northeast coast; it was the remnant of a tropical storm — like the one expected to dump rain on the Lowcountry on Monday — caught up in a winter storm.

Sandy at landfall was an outlier, a hybrid of two different kinds of storms. Among any number of odd facts about Sandy is that it dropped heavy snow in the North Carolina mountains.

“The Frankenstein storms,” said meteorologist and hurricane researcher Jason Dunion, of the University of Miami. “It is very common to see that, especially later in the year.”

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