March 9, 2012
Tornado Season 2012 – Why So Early, and Why So Severe?
Joshua Kelly, Meteorology Correspondent for Redorbit.com
Tornado Season 2012 is off to a very fast pace from our normal standards. Many things can be put together as reasons for these extensive tornado outbreaks.
One of the biggest reasons is the lack of winter that we have had this year across the United States. This allows for well above average temperatures to already be in place farther north than normal for February.
Another thing to blame is La-Nina. During La-Nina years we do see higher amounts of tornado outbreaks and that is because La-Nina drives different weather patterns which produce warmer environments throughout out the United States.
Now, to examine why we have had such an impact in the region of the Ohio River Valley and along the Tennessee River valley and also along the Southeast parts of the United States. It requires us to look into the dynamics that have set up in this region during this time period.
First, the Gulf of Mexico has been very warm this year and was not given the chance to cool off like it usually does in a typical winter scheme. This is a major component of that because it provides the moisture that is needed to fuel thunderstorm development. Also the warmer the Gulf of Mexico is the more warm moist air that is capable of rising northward.
Secondly, if we look over at the desert southwest from Western Texas back into Arizona, we can also note that conditions have been dry overall this past year and the reason this is a key ingredient is that the air moving in from here is elevated as the land has a general slope upwards as it lies on the edge of the Rockies. This air gets picked up by a very strong southwesterly wind and transported northward into the frontal systems.
The third key ingredient that has been coming into play this past month was that the Rockies are finally getting a lot of snow cover on them which allows them to provide the cold dense air in from the higher elevations.
So as we look at all three of these things coming together this year we note that the severe weather has been starting earlier this year and that is due to the lack of cold air east of the Rockies combining with our three other ingredients. When this comes together, it usually occurs this far north later in the year around May and June. These are all signs that the severe weather season has started and will be a prolonged year of interaction. We could be dealing with more of these large, severe weather outbreaks this year.
The good thing that we can take out of this year´s outbreaks is that the death toll has been lower in these storms than what we saw last year. The biggest reason for this is that people are taking the warnings seriously and preparing themselves by taking the proper action. So, as we continue to move into the severe weather season, the key impact is that people keep heeding the warnings from the National Weather Service.
A lot of people have been seeing these storms go over the same area. The bad part of this is that it´s going to keep happening as these areas are currently going through their severe weather season.
So, as we move further into Spring and severe weather season, it is important to keep our heads up and be prepared.