2018 will be the first year with no violent tornadoes in the United States
By Ian Livingston
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It was a quiet year for tornadoes overall, with below normal numbers most months. Unless you're a storm chaser, this is not bad news. The low tornado count is undoubtedly a big part of the reason the 10 tornado deaths in 2018 are also vying to be a record low.
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This year's goose-egg may seem to fit a recent pattern.
In simple terms, there have been downtrends in violent tornado numbers both across the entire modern period, and when looking at just the period since Doppler radar was fully implemented across the country in the mid-1990s. A 15-year average as high as 13.7 in the mid-1970s will drop to 5.9 next year.
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The causes for 2018's lack of violent tornadoes are many, but one key factor is high pressure tending to be more dominant than normal throughout peak season this past spring. This was particularly so during April and May, when tornado numbers were below to well below normal.
Although the country ended up seeing a number of memorable tornado events after the spring, including several this fall, in most years more than half of the tornadoes occur from March through May. Making up those numbers is difficult at other times of the year when ingredients for them are less likely.
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