NOAA’s Storm Prediction Center keeps a daily count of cumulative number of tornadoes in the U.S. each year, and recent years have had an unusually low number of tornadoes.
As of October 3, the cumulative total for 2018 is 759; the previous lowest number of tornadoes for this date was 761. The SPC has records extending back 65 years.
This lack of tornadic storms in recent years should also correlate with lesser severe thunderstorm activity in general in the U.S., since the conditions which produce large hail and damaging winds are generally the same as are required for tornadoes (strong instability, plentiful moisture, and wind shear).
via Roy Spencer, PhD.
October 4, 2018 at 01:06PM