May 22, 2012
With all of the severe weather activity in the Midwestern part of the United States, you may be wondering how likely it is to have a tornado here in Central Virginia.
From 1951-2012, there have been 701 tornadoes in Virginia. This is a much smaller number than states in the Midwest for this 62 year time period.
Jerry Stenger is the Virginia State Climatologist and talked about the history of tornadoes in Virginia and why we see fewer of them when compared to the Mid West.
Stenger said, "The middle portion of the country is very well situated to receive tornadoes because of the fact that there is hardly anything between the Midwest and the gulf of Mexico other than a barbed wire fence as they say."
When the cold, dry air from the north meets the warm, moist air of the south, you get strong temperature contracts that give rise to strong thunderstorm activity than can ultimately form tornadoes.
Just because Virginia is located on the east coast doesn't exempt us from having tornadoes. The Virginia mountains do weaken some of our storm but that doesn't mean we won't see tornadoes.
Stenger said, "To some extent, the mountains do reduce the formation of tornadoes but it would be terribly erroneous to conclude that therefore we are protected from tornadoes."
The most active time of year for Virginia occurs in September with 18 percent of Virginia's tornadoes forming during this month.
Stenger said, "The real peak in Virginia comes later on during the hurricane season. Most of the hurricanes we get in Virginia for due to the decay of tropical systems that come ashore."
Stenger said that for Virginia, a year with lots of hurricane activity tends to have more tornadoes. 2004 was the most active tornado year in Virginia with 86 confirmed tornadoes and it was also an active hurricane season.
Stenger said, "That was also the year that Virginia saw the most direct incursions by tropical systems and their remnants. So, the two are very much linked."
The deadliest tornado in Virginia occurred in Southwest Virginia in 1929 with 22 fatalities. The second deadliest hits closer to home.
Stenger said, "The second deadliest tornado in Virginia history came in 1959 when it hit Ivy and killed some 11 people. So we certainly need to remember that we are not protected from tornadoes."
With the most recent tornado devastating Oklahoma, people are pointing fingers at climate change. In reality, there is no way to know if it's to blame.
Stenger said, "Even though the number of tornadoes counted and confirmed each year is generally on the increase ,it is really impossible to tell on any analysis anybody has come up with yet if there is a true increase or just an increase in confirming and noticing these tornadoes. No one has really found a good way to normalize, if you will, the records from the past with the present in order to determine if we really are having more tornadoes or not."
The most recent tornadoes in Virginia occurred on April 19, 2013. There were two that rolled through Northern Virginia.