'Superstorm' is Strongest Ever Recorded in Midwest - More on the Way?

Image credit: NASA/GSFC.

The strongest storm ever recorded in the Midwest swept through Minnesota, bringing fierce winds and torrential downpours along with it. It turns out the 'superstorm' caused the lowest pressure ever recorded in a U.S. non-coastal storm--955 millibars. The storm was stronger than the Great Ohio Storm of 1978, the previous record-holder, and stronger even than the storm that famously sank the Edmund Fitzgerald on Lake Superior in 1974. That's according to meteorologist Jeff Masters, who goes on to note that "We've now had two remarkable extratropical storms this year in the U.S. that have smashed all-time low pressure records ... Is this a sign that these type of storms may be getting stronger?"Masters answers his own question, saying that "there is evidence that wintertime extratropical storms have grown in intensity in the Pacific, Arctic, and Great Lakes in recent decades."

The short of it is that yes, these types of storms may indeed be getting stronger as the globe warms -- but they may also be getting more infrequent. Masters explains that since warming impacts the poles more than the equator, it reduces the temperature differentiation between them. Since winter storms form due to the need to move heat from the equator to the poles, there will be less need for winter storms. But.

Since warmer temperatures increase evaporation, and puts more moisture in the air, the amount of precipitation these storms carry will increase as well. Which means that as global climate change continues, we'll perhaps see fewer, but wetter storms: So when it rains, it will really pour. Rimshot. But that's not all.

Masters explains why its the case that the added precipitation will lead to stronger, more violent storms:

During the process of creating that precipitation, the water vapor in the storm must condense into liquid or frozen water, liberating "latent heat"-the extra heat that was originally added to the water vapor to evaporate it in the first place. This latent heat intensifies the winter storm, lowering the central pressure and making the winds increase. So, the modeling studies predict a future with fewer total winter storms, but a greater number of intense storms. These intense storms will have more lift, and will thus tend to drop more precipitation-including snow, when we get areas of strong lift in the -15°C preferred snowflake formation region.
So, expect to see more superstorms like the one that wracked the Midwest as climate change continues -- and we continue to do nothing about it.

More on Global Climate Change and Storms
Why Won't the Media Report the Link Between Global Warming and Extreme Weather
Higher Number of Atlantic Storms Linked to Global Warming
Rising Seas and Powerful Storms Threaten Global Security

Tags: Global Climate Change | United States


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