by Charles the moderator, December 27 2018 in WUWT
From LMT Online
In the whirlwind that is 2018, there has been a notable lack of high-end twisters.
We’re now days away from this becoming the first year in the modern record with no violent tornadoes touching down in the United States. Violent tornadoes are the strongest on a 0 to 5 scale, or those ranked EF4 or EF5.
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 is also vying to be a record low.
While we still have several days to go in 2018, and some severe weather is likely across the South to close it out, odds favor the country making it the rest of the way without a violent tornado.
If and when that happens, it will be the first time since the modern record began in 1950.
by NOAA, August 2018
One of the main difficulties with tornado records is that a tornado, or evidence of a tornado must have been observed. Unlike rainfall or temperature, which may be measured by a fixed instrument, tornadoes are short-lived and very unpredictable. If a tornado occurs in a place with few or no people, it is not likely to be documented. Many significant tornadoes may not make it into the historical record since Tornado Alley was very sparsely populated during the 20th century.
Much early work on tornado climatology in the United States was done by John Park Finley in his book Tornadoes, published in 1887. While some of Finley’s safety guidelines have since been refuted as dangerous practices, the book remains a seminal work in tornado research. The University of Oklahoma created a PDF copy of the book and made it accessible at John Finley’s Tornadoes(link is external)
See also here
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