Google Search

For weather information from across the nation, please check out our home site National Weather Outlook. Thanks!

Washington DC Current Conditions

Washington DC Weather Forecast

Washington DC 7 Day Weather Forecast

Washington DC Metro Weather Radar

Wednesday, January 2, 2013

A Terrible Tornado Year

*** Note: This blog was updated on June 19 to reflect new data that has come in on the number of EF5 tornadoes and tornado fatalities ***

Unless you live under a rock, as the saying goes (as featured in a current commercial), you must be aware of what a horrific year it has been for tornadoes. Only the pictures of the death and destruction can give the full picture of just how awful it has been. But I thought I'd present a little data to tell the story in a less traumatic way.
The table below gives the preliminary tornado counts for the spring and year-to-date (through June 12). April was the huge anomaly. Its 762 preliminary tornadoes are over 200 more than the previous record for any month (542 in May 2003). The 1282 tornadoes through June 12 are as many as the United States had in all of 2010! Only six years on record have had more tornadoes for a full year. Thanks to April, we're on a record yearly pace. Fortunately, the pace in June has slowed down to well below average thus far. Springfield and other Massachusetts communities, unfortunately, weren't spared on June 1.

The pace in May was barely above average number-wise, but it featured the ultra-deadly EF5 tornado in Joplin Missouri on May 22 and another EF5 tornado in Oklahoma on May 24. This brings the number of EF5 tornadoes for 2011 to 6. Only 1974 had more. The Joplin tornado is the deadliest tornado in the United States since 1947.

The table below shows how violent and deadly 2011 has been relative to an average year. The 540 deaths are the most for a year since 1936. The 56 killer tornadoes are the most since 1974 and ninth-most on record since 1880. Prior to 1974, you have to go back to 1942 to find another year with more killer tornadoes than in 2011!

Following the April 26-28, 2011 tornado outbreak, I wrote a
blog pondering how many records set in the April 3-4, 1974 Superoutbreak would fall. While the totals aren't final or official, April 27 beat out the 1974 Superoutbreak in number of tornadoes, number of deaths, and number of tornadoes with widths of 400 yards or more. No wonder that some are calling it the "2011 Superoutbreak."

By my method of defining a tornado outbreak, there was a actually a 49-hour tornado outbreak from the afternoon of April 26 through the afternoon of April 28, 2011. This outbreak set new records for any known outbreak for numbers of tornadoes (at least 259), number of tornadoes with width of 400 yards or more (at least 52), combined tornado paths (over 2600 miles), and number of states hit (18).

The 1974 Superoutbreak still holds several records, including the numbers of tornadoes rated F2 and higher, F4 and higher, and killer tornadoes. Certainly these helped it to cause approximately the same number of deaths as in the 2011 Superoutbreak.

What has been most shocking to me is that 2011 has brought so many tornado deaths in this era of excellent Doppler radar-based tornado warnings, excellent advance forecasts, and multiple ways of communicating/receiving tornado warnings and weather forecasts. Yet the death tolls are like what took place before there was any weather radar; before there were any tornado warnings issued by the National Weather Service; before there were any computers! I never thought I ?d see these death tolls nowadays.

I suppose that the message from the deadly 2011 tornadoes is that warnings aren't enough when the tornadoes are violent with long and wide paths. That combination of path width and length gives so much area having winds in excess of 100 mph that too many homes get hit and destroyed. And when the path hits communities, the toll is high. Urban sprawl has increased the target areas of these metropolitan "bulls-eyes." The safety rules of going to the lowest, innermost location in your home raise your odds of surviving, but aren't absolute guarantees. There are few places that are safe in a violent tornado. Being in an underground storm shelter or a specially built in-home storm shelter is the only way to be absolutely safe.


View the original article here