In terms of violent tornadoes, the ones that reduce entire neighborhoods to matchwood, why is the USA especially susceptible?
It turns out that the reason is geologic. Specifically, the U.S. does not have an East-West mountain range, and the same is true for Canada. Thus there is no impediment to the warm humid air from the Gulf of Mexico being able to easily mix with cool, dry air from Canada. And when other factors, such as what’s called a jet max, come into play, the stage can be set for a devastating outbreak of severe weather that is sometimes so horrific, it leads the national news.
Now when compared to tornadoes, many people think that severe thunderstorms are no big deal, but this is certainly not the case! Severe thunderstorms are those which produce damaging winds and/or damaging hail. A major aviation hazard presented by severe thunderstorms is called a microburst, (Sometimes you’ll hear the term “straight-line winds” when damage assessments at microburst sites are conducted).
A microburst almost downed Air Force One, with President Reagan aboard, on August 1st, 1983. The plane landed at Andrews Air Force Base, just outside of Washington D.C., just six minutes before a violent microburst struck the very same runway, with a wind gust measured at an incredible 149 mph. Microbursts can easily slam an aircraft right into the ground, and again, President Reagan beat it by just six minutes! Modern radar that can detect microbursts, was not implemented at that time.
Now, this might surprise you: while severe weather does visit The County each and every summer, the most likely “life-threateners” you will encounter here in The County are flash floods and lightning, and those can and do occur from thunderstorms that are not necessarily classified as severe!
Finally, returning to a national perspective as we close this column, those violent tornadoes, the neighborhood-levelers, are most likely in the Plains, where those two different air masses can easily meet, basically between the Rockies and the Appalachians.
Ted Shapiro holds the Broadcast Seal of Approval from both the American Meteorological Society and the National Weather Association. An Alexandria, Va. native, he has been chief meteorologist at WAGM-TV since 2006. Email him at tshapiro@wagmtv.com.
