Your Survival Blog
And I looked, and, behold, a whirlwind came
Eastern North America gets hurricanes. Half the year is officially “hurricane season” — the beginning of June to end of November — because the overwhelming majority of hurricanes occur in those months. (The end of the season used to be considered October, but in the twentieth century too many hurricanes wandered along in November, so the official crew expanded the definition.) Most hurricanes and tropical storms, in fact, are bunched together in just three months, August through October; the beginning of September is the worst.
The western coast of North America has a similar season, mid-May through the end of November.
Other areas of the world have their own seasons. East Asia gets typhoons all year, though with a peak in late summer; India has two peaks six months apart; the Southern Hemisphere regions tend to have seasons like North America’s, only in reverse — November to May.
In the North Atlantic, 2008 was a well-above-average year, with 16 named storms, eight hurricanes, five major hurricanes; never before, since records have been kept, had there been a major Atlantic hurricane in July, August, September, October AND November. The worst year on record was 2005: 28 named storms, fifteen hurricanes, seven major hurricanes — and four of those Category 5, the worst sort of all.
In comparison, 2009 began with a fizzle, with no named storms in June or July. (El Niño in the Pacific, say meteorologists, is shifting the jet stream south and disrupting storm formation.) Of course, 1992 started sluggishly as well — yet the very first named storm, Hurricane Andrew in August 1992, brought a gigantic swath of destruction.
June too soon.
July stand by.
August look out you must.
September remember.
October all over.
—R. Inwards, 1898
By contrast, tornadoes don’t quite have a “season,” at least in the US, where weather conditions have proved favorable to tornadoes year-round. They do, however, have peak seasons, depending on the state: in the Northeast, June through August; in California, January through April; in the Gulf states, spring with another peak in November; in the Midwest’s Tornado Alley, the spring or early summer, becoming later as you move north.
Last June, storm-chasing scientists announced that the 2009 tornado season had been a disappointment, with fewer tornadoes and less intense ones than in previous years to date; there was even a 17-day stretch in late spring with no tornado watches anywhere in the US. This may have been bad news for thrill junkies, you might think, but isn’t the good news that many fewer people died in tornadoes than the preceding year?
On the other hand, the storm chasers — from four countries and a wide array of institutions — weren’t doing it just for thrills, they were hoping to apply their instruments to tornadoes to see exactly what made them develop, and what happened when they did. (The experiment is called VORTEX2: Verification of the Origins of Rotation in Tornadoes Experiment 2. It had ten million dollars in funding from the National Oceanic and Atmospheric Administration and National Science Foundation, and will return during the spring of 2010.) Among their goals was to see whether warning times — now less than fifteen minutes — could be expanded to half an hour or even a full hour.
Oddly enough, NOAA records show that there were not significantly fewer tornadoes in 2009 than in the previous several years. It’s possible the VORTEX2 crew put out their instruments during a lull, or were simply looking in the wrong spots. It’ll be an interesting project to watch....
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