Hurricane repellent: U.S. luck continues

Although two Category 4 hurricanes, Igor and Julia, are churning the North Atlantic into a giant mug of cappuccino, the waves of anxiety aren't reaching the U.S. East Coast.

Igor may threaten Bermuda, and the latest forecast map shows Igor and Julia becoming involved in a ferocious, almost salacious dance, but one that East Coast resident should be able to enjoy safely from a distance.

With Tropical Storm Karl heading toward Mexico, thus far the 2010 season has produced 11 named storms -- those with winds of at least 39 m.p.h.

That means the Atlantic Basin season, which continues through Nov. 30, already has matched its annual average for named storms. If Karl gains winds of at least 74 m.p.h., as expected, it would become hurricane No. 6; the annual average is 6.

Despite all that activity, however, so far this has been the second consecutive season without a hurricane landfall in the United States.

That led us to wonder how many hurricane seasons have passed without a U.S. landfall; whether any of those were  seasons with above-average activity, and how often hurricanes shunned both the Atlantic and Gulf Coasts in back-to-back years.

Using data from the National Oceanic and Atmospheric Administration, we confined our search to the last 50 years. In the satellite era, tropical-storm detection and monitoring is far superior to what it was in the 19th and first half of the 20th Centuries.

We found a total of 14 seasons without U.S. landfalling hurricanes, or just under one every four years. Of those 14, four had above-normal numbers of both tropical storms and hurricanes.

As for back-to-back years without U.S. landfalls, we found four cases. The first three are follows: 1978-79, both near-average years; 1981, above average, 1982, below; and 1993-94, both below.

But perhaps the most-encouraging case for the rest of the season would be 2000-01. Both seasons were quite active with a total of 30 named tropical storms and 17 hurricanes. Yet not one of those 17 made U.S. landfall.

As we all know now, the luck would run out in 2004 and 2005, but it's at least possible that it will continue the rest of 2010.