Will Tornado Season Be as Bad as Last Year?

Frequent and intense tornado outbreaks resulted in 552 tornado-related deaths in 2011, the second deadliest year on record, from 1,709 tornadoes. The over three dozen of tornado-related deaths in the past week, along with 165 preliminary reports of tornadoes, is raising fears that this will be another devastating year for tornadoes.

Overall atmospheric conditions in the coming months will not be as conducive for tornadoes as they were last year -- but an active season is a possibility.

It was the combination of unseasonably warm air in the southern part of the country, cooler-than-normal air in the northern tier of the country, and an active spring and early summer storm track fueled by an ongoing La Niña that set the stage for the devastating season last year. These are factors that wereanticipated by forecasters.

This year, the Climate Prediction Center (the government's long-range forecasting experts) expects some similarities to last year, but there will also be significant differences.

The main similarity is expected warmer-than-average conditions in the southern tier of the country, and since a warm, moist flow from the Gulf of Mexico is a prime factor in the formation of severe thunderstorms and tornadoes, this factor alone indicates that the season could be more intense than an average season.

Fortunately, however, it seems less likely that temperatures will be cooler-than-average across the norther tier of the country. If it is not as cool in the north as it was last year, then the contrast between the warm and cool air will not be as intense, a factor that would tend to reduce the number of widespread tornado outbreaks.

While the temperature contrast between the warm and cool air is the potential fuel for devastating thunderstorms, an active storm track is necessary to activate this fuel. With the La Niña that influenced the weather through winter quickly dissipating, it is not likely that the storm track will be as active this spring into summer as it was last year. That's one of the major implications of a La Niña -- a more active storm track across the northern part of the country.

Even an average season poses considerable risk for tornadoes -- the year with the fewest number of tornadoes this century, 2002, had 938 tornadoes, including over 200 during the month of May. Tornadoes can occur in any month, but April and May are typically the months with the highest tornado frequency.

And it only takes one tornado over a populated region to turn a mild season into a particularly tragic one.

 

 

 

Comments

[FTracy3]

04:11 PM on 03/05/2012

So the answer to the question is, "Maybe."

[pmag88]

02:56 AM on 03/05/2012

If it is not as cool in the north as it was last year, then the contrast between the warm and cool air will not be as intense, a factor that would tend to reduce the number of widespread tornado outbreaks.

I hope you are correct, but last year it seemed like the confluence of wind from the south and northwest had a lot to do with it.

[Sunwyn Ravenwood]

04:51 AM on 03/05/2012

That is exactly what he said, cold air from the NW and warm wet air from the South come together to form storms that breed tornadoes.

[pmag88]

02:56 AM on 03/17/2012

Actually, last year hot dry air from the southwest was also a major factor. This year it doesn't seem the winds are fired up yet, and hopefully they won't,be, but it's early in the season.
,
It looks like it might be a horrific fire season all accross the U.S. this year. Again, hopefully not.

[BigBearcatBill]

12:43 AM on 03/05/2012

Tornado prone areas of country should start building underground shelters and cellars for all housing areas so people can go below earth in these, that is how the many thousands of farm families survived over the last couple of centuries. These can be so strong they are going to rip some houses completely up and lift out the occupants, and you don't know when and where it is going to happen so build these everywhere. Oh no the budget worriers will say. but how much is a human life worth? In a law suit could be $100 million or so if they really need to know. Let's go feds and states, show concern for emergency preparedness and human life, there is no excuse in these times not to be able to save every life in about every tornado situation if there are enough underground shelters and plans to get people to them in time.

[Sunwyn Ravenwood]

04:52 AM on 03/05/2012

I have never understood why this is not mandatory. I also do not understand why trailer parks are allowed in tornado prone areas since they offer zero protection.

[BigBearcatBill]

12:28 PM on 03/05/2012

Yes you would think someone would haved designed a better stabilizing system for mobiles and trailers in these areas, some special extra tie downs planted solidly. At the least these parks need the underground shelters to be built ASAP, it is pretty sickening to think that a person could be swept away and they could have been in a small underground cellar like the farm families have done for centuries. No excuse for emergency planners that ignore this.

[Haveissues]

08:45 AM on 03/05/2012

That may not be a bad idea. I live in Texas and they have sirens installed throughout the cities in the DFW area. Usually, when the sirens sound, the neighbors come out of their houses and gawk at the sky.

[WitsendNJ]

10:35 PM on 03/04/2012

Did you actually write about the increasing number of tornados and NOT mention the contribution from climate change?

MunichRe and other insurance giants understand the connection between rapid increases in property losses from violent weather - why don't you?

Charts from their latest reports can be seen here: http://witsendnj.blogspot.com/

No explaining that science predicts exactly this sort of devastation from climate change is a disservice to HuffPo readers.