Tuesday, January 1, 2013

“I’m not angry. I’m disappointed…”
Jack Hall, Day After Tomorrow
  • By Zachary Fasnacht, Winter Stormcast Director | Jason Isaacs, Southeast Education Coordinator

    6:50 PM EST 1/01/13 A lot of questions have come up the past few weeks asking us…“What happened to the snow?” Well, the truth is just like in the Day After Tomorrow, “we are not angry, we are disappointed” with the outcome of the recent events. The purpose of this article is to explain the past projections, the current trends, and what the future holds for the Mid-Atlantic region. 

    But, wait? As Sam Hall tried to explain the truth to his father, his father asks an important question. “Sam, how can there be two sides?” Well, in meteorology we know that everything cannot be perfect and revisions are a necessary part in any winter forecast. So, we are going to go against Jack Hall and explain the other side of the story.

    Since there are two sides to every story, we need to start at the beginning. 

    In the Day After Tomorrow, the climatologists started with projections. Our projections were interesting since we were having discussions on how the upcoming winter would conclude. As we went into the beginning of the Winter we were unsure how it would turn out as we were trying to decide when the cold air would make its appearance into the Mid-Atlantic region from Canada. 

    Here are our original predictions from Early December as we looked ahead into the upcoming Winter: 
    This winter is going to be a tricky one to predict as we have seen so far. The models are not doing well in the long range as we have seen over the past few weeks with them mishandling the timing of the cold air into the Eastern U.S. It does look like this Winter will swing back and forth between warm and cold periods. We will be stuck in a neutral ENSO state this Winter which in the past has led to Winters that did have record warmth as well as some snowstorms. 
    The big factor with this Winter will be having the cold air come down and a storm form right after the cold air comes down as it does not look like there will be extended periods of cold weather. For this reason, the expectation is that areas from southern PA southward through MD and VA, as well as eastward into NJ and NYC will see below average snowfall this year.  
    Areas in northeastern PA and northeast through central NY and western CT should see average snowfall. Finally, places west of I-81 can expect to see above average snowfall this season.
    The real story of the winter has been snow, and temperatures. As seen in the graph below the mean temperatures, during the month of December was considered warmer for the entire region. The warm weather in the beginning of the month has kept the mean temperatures across the region well above normal. 

    For those who do not remember, the first week of December was very unseasonable with many areas seeing near record highs in the lower 70’s. This warmth would last a week before cooler air moved in, but this cooler air did not change much. While around 10-20 degrees cooler, temperatures remained a few degrees above average for another week. It wasn’t until mid-month that seasonal temperatures returned to the mid-Atlantic. The true winter air arrived for the week of Christmas, but as it was not too extreme, and just a touch cooler than normal, the mean temperatures for the month remained above normal across the region.

    So, how are our predictions doing at the moment? 
    Well, just like in the movie…they were not completely correct. Where scientists thought the climate would change over thousands of years, their timing was a little bit off. For u, the timing issue was a matter of figuring out when cold air from Canada was going to head south. We kept thinking it would happen in Mid-December, but it did not arrive until the latter half of the month. So, while a little off on our timing, we were not off on our snowfall predictions.

    While we know that everybody would love to see the several feet of snow that was produced in the movie. However, we can say one similarity, our weather over the past few weeks have been changing extremely rapidly. Looking at the beginning of December, the entire Mid-Atlantic was stuck in a completely different pattern…actually a pattern that does not smile on snow lovers. 

    This pattern produced a warm air mass as the jet stream was well north of the area and had the cold air trapped in the Northern Plains. Now as time progressed, the weather would start to favor the people who enjoy the cold. The jet stream slowly pushed east and the cold air finally started to make an appearance. By mid-month, the northern portions of the mid-Atlantic were beginning to experience the cold air, but were still lacking any large snows.

    Rapidly, a few days before Christmas the jet stream moved through part of the mid-Atlantic, providing enough cold air to produce snow in some areas. We saw our first snow, which was light in all areas, on Christmas Eve night, dropping as much as three inches across the mid-Atlantic. While nothing major, it was the beginning of something bigger. By the day after Christmas, a much larger storm had arrived. While, most areas started as snow, areas in southern and coastal portions of the mid-Atlantic changed over to rain quickly. 

    As the storm strengthened more interior regions stayed all snow and received major snowfall accumulations between 6 to 12 inches. But, just when you thought we would have these storms come to a conclusion…there was yet another storm. This last storm during Christmas week would end with yet a third snowfall which dropped an average of 2-6 inches across the mid-Atlantic, with again the interior regions receiving the higher amounts.

    In the movie, Jack Hall shows us a historic storm that would most likely never occur in our lifetime. While, we will not have that type of storm, he explained to the President what this type of storm would produce and how it is different from the average storm. So what does this mean for us while comparing our weather to average? 

    Well, as we look at the graph here, we see that the interior areas got major snowfall from the second storm. These locations included Pittsburgh and Williamsport and are well above average now when it comes to snowfall. 

    While other areas such as Baltimore and Philadelphia, saw a few light snows, which caused the area to be slightly below average when it comes to snowfall so far this year. The sad part about the recent snowfalls includes the coastal areas such as Atlantic City and New York City which are still waiting to see the cold air reach their neck of the woods, which had produced mostly rain and very minimal snowfall.  

    What can we expect into the future? Well, this is now the other side of the story that Jack Hill believed didn’t exist. As we move into the first week of January, we sadly think that the weather will rebound and the possibility of snow looks less likely. According to the Climate Prediction Center 8 to 14 day outlook (shown below), well above temperatures are projected through the middle of the month.

    While some areas in Maryland and Virginia could receive some light snow as a few week systems move through the south this week, it will not produce much snow at all as it will quickly skirt off the coast. These systems are being suppressed by the jet stream, which will provide plenty of cold air over the west for the first week of 2013. Much of the Mid-Atlantic will be seeing above average temperatures as we move into the beginning of the year.

    We will leave you with this thought…“well we’ve found something extraordinary…extraordinary and disturbing.” If you are a snow lover the next few weeks will not be your friend. However, the rest of the Winter looks interesting and we will release these findings very soon.


Unknown said...

I just love interesting findings. I'll be willing to settle with the 6-8' I've gotten so far for a few weeks. I just need that other half of winter to come through.

ravensbbr said...

Daggone I love me a weather site that actually LIKES snow. :-)

Unknown said...

Major Strat warm to collapse the polar vortex within weeks. This will pour artic air into the US by the 3-4 week of Jan! Record cold is coming. This should remove the SE coast ridge and open the Gulf for business.

Unknown said...

I really hope this is true, Mike!

ravensbbr said...

Andy, your thoughts on the above comment re: polar vortex?

John said...

This cold air is a waste if we aren't getting any snow. I am beginning to think we are in for another snow drought.

Unknown said...

I posted my comment Jan 2. Please read the article posted on accuweather.com. The title is Brutal cold weather could be headed for US. written by Alex Sosnowwski on Jan 4th! Read how he says the cold will erode the block off the SE coast. This is what we need to get the southern branch of the jet cranking! Don't lose heart my friends.

Andy, Southern York County Pa said...

Here in the mid atlantic it will become significantly colder next week. There is little chance that we see a plowable snow before the 20th. Generally cold and dry conditions will dominate. The only chance I see is a pre or post frontal type event that could sneak up on us and hit us with a 1-3 inch event if we are lucky, although I would not count on it. I will be back in 9 days to see what the final third of the month has in store for us.