CINCINNATI, OH (FOX19) - The number of tornado watches that have been issued this year in the U.S. is the fewest to date in the past 13 years.
NOAA's Storm Prediction Center (SPC), which posts tornado and severe thunderstorm watches in the U.S., has issued only 63 tornado watches through July 9, according to Sam Lillo, a meteorologist at the University of Oklahoma.
Tornado watches are put in place when atmospheric conditions are favorable for the development of tornadoes in any particular area.
According to SPC, the latest date that the 63rd tornado watch was issued was May 16, 2016. This year, however, the 63rd tornado watch was not posted until July 1. In the past decade, this point has been reached in April in most years.
Given the below-average number of tornadoes this year, the reduced number of tornado watches is no surprise.
So, what's going on?
The jet stream drives weather. This year the jet stream has not frequently been in a position conducive for tornado outbreaks, which has limited the number of watches and warnings. While this does not mean that this trend will continue through the end of the year, the most active months for tornadoes – April, May and June – have passed.
In most years, close to two-thirds of the annual tornadoes have occurred through June, based on data over the last 20 years.
Only three deaths due to tornadoes have been reported this year, and for only the second time on record May and June passed without any deaths. The other year that this occurred was 2005, which also saw well-below average tornado reports through June.