Sunday, October 28, 2012

2012 Halloween Storm, Perfect or Not

The big story this year around Halloween is Hurricane Sandy and whether it will become the next "Perfect Storm".

There has been a couple of names being thrown around for the situation of Hurricane Sandy such as "Frankenstorm" and the next "Perfect Storm".  "Frankenstorm" is just wrong to begin with and probably comes from one of two things, Halloween is around the corner or that it is and will continue to be a huge storm.  Either way, if "Snowmageddon", "Snowpocalypse", or any other word with "snow" in front of it can't be used then neither should "Frankenstorm".  Now the next "Perfect Storm" as compared to the 1991 Perfect Storm, that is a lot more realistic.

In 1991, a storm developed into something highly unusual and was deemed as "The Perfect Storm".  One question remains, what is the "perfect storm"?  Well, there are not any specific requirements or qualifications dubbed by any meteorological organization that would make a storm "the perfect storm".  So, how did it come up?  The name was given to the storm system in 1991 by the Boston NWS forecaster Robert Case and the author of the book "The Perfect Storm" Sebastian Junger.  Case described the situation of the storm as the "perfect situation" based upon 3 weather-related phenomenons that came together to develop the 1991 Perfect Storm.  These phenomenons were warm air from a low-pressure system, a flow of cool and dry air generated by a high-pressure, and tropical moisture provided by Hurricane Grace.  This started the topic of naming the storm "The Perfect Storm".

Does that mean that it could be the only "perfect storm"?  Will this be the end of the quotes?  Nope and not quite.  The storm in 1991 was called the "perfect storm" because it was an event where a rare combination of circumstances that aggravated a situation drastically.  It could also be described as a phenomenon that happens when such a confluence of phenomenons that result in an event of unusual magnitude.  Because of those definitions, it can be called a perfect storm.  By that definition, what we are forecast to experience in the Mid-Atlantic and Northeast regions of the U.S. is considered a "Perfect Storm".  Also, if you want to look into other storms, the April 27th tornado outbreak can be considered as a "Perfect Storm" as a number of factors came together to develop a one of a kind severe weather event.

Now, the final match up!
 VS 

Who will cause the worst damage?  Sandy from Grease or Grace from Will and Grace.  Hard to say for those two, but the outcome of Hurricane Grace in the 1991 Perfect Storm and what may become of Hurricane Sandy we will see after a few a days.  For right now let's do a comparison.  Here was the setup for the 1991 Perfect Storm.

Shortly after the time the observations were taken for this map, the low to the far right deepened to a 972 mb low with a high-pressure over the Montana/Dakotas region that was 1044 mb and another high-pressure to the north of the low that was 1041 mb.  The pressure difference between them was around 70 mb from the one to the north and the one to the west, but the one to the north had the largest pressure gradient which resulted in the strongest winds and highest waves which is what caused all the damage in the Nova Scotia area as well as a number of ships such as the Andrea Gail.  Now what about the setup for the storm that's going on right now.

Hurricane Sandy is out off of the North Carolina coast with a pressure of 951 mb and to the west in The Great Plains is a high-pressure of 1030 mb.  That's a pressure difference of nearly 80 mb.  So far, this storm isn't done and will be heading directly into the Mid-Atlantic and southern portions of the Northeast.  This storm also has the same relative ingredients that made the storm in 1991 very notorious.  Sandy is a hurricane with moisture and a source of heat from warm waters along the Atlantic Coastline, a powerful cold front to the west with significant dry air, and a high pressure system.  So will this be another storm to be deemed as another "Perfect Storm" like they did 21 years ago or will the NWS eventually stop calling it Sandy and start calling it Athena in their latest attempt to name winter storms?  Right now, the answer is unknown, but as Sandy continues to move north and then northwest with its very low-pressure we will see what they do with it.