We've Been In A Hurricane Drought For Nine Years

May the odds be ever in our favor

Hurricane Wilma

Hurricane Wilma

NOAA/Wikimedia Commons Public Domain

Want to know a secret? First, knock on wood, and whatever you do, don't tell the hurricanes, ok? This news might inspire them to pick up the pace, and we wouldn't want that.

Now that we've covered all the superstitious bases, here's the good news: a major hurricane hasn't hit the United States for the past nine years!

And who else could we thank for our good weather fortune than Lady Luck? A study published in Geophysical Research Letters last month found that the United States managed to beat the odds, gaining a nine-year respite from hurricanes larger than a Category 3. A Category 3 storm on the Saffir-Simpson scale involves sustained winds above 111 miles per hour, and is expected to cause devastating amounts of damage, blocking roads, damaging buildings and knocking out electricity and water services. There is a 39 percent chance that one of these major cyclones will hit the United States in any given year, but so far we haven't had one since Wilma, back in 2005.

Of course, smaller tempests did strike the U.S. during this hurricane 'drought.' Three years ago, Sandy swept through the Northeast, leaving a devastating and costly wake. But when the storm made landfall in the United States, it was a post-tropical cyclone stripped of its hurricane status as it weakened.

The researchers wanted to know just how strange this drought was. To get a better sense of whether or not the severe storms' lack of landfall was an outlier or not, they looked at historical records and ran computer simulations of hurricane seasons from 1950 to 2002. They ran the simulations 1,000 times and estimated that a 9-year stretch like this is likely to occur only once in about 177 years.

Records of hurricanes in the United States have only been kept since 1851, just 164 years ago. So while this is the longest drought in recorded hurricane history, statistically speaking, it was bound to happen sometime.

The future is still uncertain. Hurricanes remain difficult to predict accurately, and climate change remains an unknown factor in these huge storms. NOAA's Geophysical Fluid Dynamics Laboratory (GFDL) has a detailed overview of current research into a link between global warming and hurricanes. Their conclusion so far is that:

"It is premature to conclude that human activities--and particularly greenhouse gas emissions that cause global warming--have already had a detectable impact on Atlantic hurricane activity. That said, human activities may have already caused changes that are not yet detectable due to the small magnitude of the changes or observational limitations, or are not yet properly modeled (e.g., aerosol effects)."

But even if it's too early to make definitive conclusions, the GFDL does have some guesses as to how hurricanes of the future might change. They say that there is a good chance that over the next 100 years anthropogenic (human-caused) global warming could make hurricanes more intense globally, more numerous in a few areas, and dump way more rainwater than our hurricanes today.

In the meantime, everybody cross your fingers that this year's hurricane season (June 1 through November 30) manages to keep the streak alive. A decade without a major hurricane making landfall? That would be incredibly lucky.