The air is getting colder, and for many areas, the first flakes have already flown. Ah yes, what looks to be yet another cold and snowy winter is soon to be upon us. The past several winters have generally featured above average snow with frequent cold shots. I expect more of the same as we head into the 2018-2019 winter season. Meteorologists and climatologists have yet to reach 100% accuracy for these forecasts as seasonal forecasting is still an evolving science and can only be so accurate for any given area. There are many factors that go into making a seasonal forecast such as teleconnections, sea surface temperatures of the Pacific ocean, Sunspot progression, Siberian snow cover, analog years (past winters that have a similar upper air pattern to the winter I am expecting this year) and much more. Nevertheless here is my forecast for the upcoming 2018-2019 winter!
The first factor I took into consideration when coming up with this forecast was the current ENSO state. ENSO stands for El Nino - southern oscillation and generally it gives a good indication of what to expect for our upcoming winter. Below is a map depicting the current Sea Surface Temperature Anomaly. This basically shows how cold/warm the waters are and how far they differ from their averages for this time of year.
The main area of interest is in the eastern Pacific Ocean. Off the western coast of South America, we can see that waters are above normal. This indicates that we are in an El Nino state. The ENSO state changes from year to year and is highly variable in the long range. Last year was a La Nina winter which meant the waters off South America were below normal. Our last El Nino winter, 2015-2016, was nearly record strong and produced average snowfall and well above average temperatures for much of the eastern third of the country. This year I do not expect the same as we have a weak-moderate, central based, El Nino year. These years usually give our neck of the woods cold and snowy winters. This occurs because as the ocean warms in the El Nino region, it creates convection and thunderstorms. This convection leads to a kink in the jets stream which produces a ridge over Alaska, which in turn makes a trough over the eastern United States. Troughs bring cold air down with them and form storms along their boundaries. It is highly likely that a trough dominates over the eastern United States for much of this winter.
Taking a closer look at sea surface temperatures we can see that the waters off the east coast are raging well above normal this year.
This is significant because as storms form in the southern United States and move eastward they will encounter these warmer ocean waters. A warm ocean off the east coast screams big snowstorms to me as these waters will act as fuel. You will likely hear the terms bomb cyclone or that a storm is “bombing out” a lot this year as these warm waters will allow for cyclones to deepen.
Another factor of note is the current sunspot cycle of our sun. We are at a solar minimum. There is a weather theory that low activity in our sun can create a weaker polar vortex. You have probably heard of the polar vortex as it has become a buzzword in social media. The polar vortex is basically a broad term to describe the state of the upper atmosphere around the north pole. When the polar vortex is weak the air that is usually trapped in and around the north pole can, essentially, leak out. When there is a “leak” or weak area in the polar vortex the air will come down towards the United States. How will we know where the air will end up? By where the jet stream is situated. I spoke about before how I expect the trough to be dominating the eastern United States and with a weak Polar Vortex, we will see frequent cold shots.
Back to the current sunspot activity, you can see that we are nearing another solar minimum in the solar cycle. Now, this does not guarantee that we will have a cold winter but past years have alluded to this theory being correct. Take 2007-2011 for example, those years were generally quite cold for the east coast. Those all also happened to be solar minimum years as well. Now take a look at 2015-2017. Those years were coming off of a solar maximum and featured warm temperatures.
Now we can take a look at the current snow cover around the Northern Hemisphere. This will usually lead to clues on how cold/snowy the winter is going to be. Above average snow cover usually means above average cold and snow for much of the United States and vice versa.
As you can see there is a lot of snow throughout the northern hemisphere, however, I will take a look at the current snow depth specifically in Eurasia as that can give us more clues to how the winter will shape up.
As we can see here the current snowfall anomaly is showing that snowfall is slightly above average. This is yet another sign that points to a colder than normal winter. A higher Eurasian snow cover can produce stronger high pressures in the area. This, in turn, can disrupt the Polar Vortex and lead to cold air spilling out as I spoke about before.
We can also look at some years past that look similar to what I expect this year to look like. Two recent years that instantly came to mind when creating this forecast were the 2002-2003 winter and the legendary 2009-2010 winter. These years had similar upper air patterns to what I expect this year. Let's take a look at how those years shaped out temperature wise.
When combining the average temperatures of these two years we can really see that in those years the eastern two-thirds of the country ranged well below average temperature wise with just the west coast picking up a milder winter. I believe this year will feature much of the same.
If you read all that, thank you it took a while to create. But here is the part everyone came here for. My official 2018-2019 winter forecast. First off we will start with temperature anomalies.
I have -3°/-5°F for much of the coverage area with -1°/-3° for much of the Midwest and much of the northeast. I believe all of the southeast will experience a frigid winter with much of the rest of the eastern half of the country experiencing below normal temperatures for much of the year. Although one to three degrees below normal may not sound like much it is. I am expecting plenty of record cold snaps throughout the year especially focused in February and March. I expect most of the 1st half of December to remain below normal, then averaging outcome the second half of the month. The first portion of January is expected to be quiet and maybe slightly above average before we head back to the freezer for the rest of the winter. I expect February to be the coldest month and for temperatures to remain below average for most of the east.
Next we have everyone’s favorite: the snowfall outlook. If you do not like snow now may be the time to look away.
For snowfall, I have a wide swath of 150% above normal snowfall from Jackson Mississippi to coastal southern New England. 125% above normal snowfall will range just outside the 150% area that spans Saint Louis, Cincinnati, and Boston. I believe much of the deep southeast will experience 125% above normal snowfall as well, that includes the Gulf coast to Savannah. Nearly every factor I looked at points to above normal snowfall for much of the area and I could even see some places experiencing 175-200% of their normal snowfall. The jet-stream should dip enough to all for a multitude of coastal storms to form and ride along the southeast and drop more snow and ice than is usually seen. I suspect multiple big Nor’easters and 1-2 blizzards as storms will be juiced up once hitting the warm Gulf Stream off the east coast. I also suspect that we could see a few March and even April snowstorms as the old should persist long enough into spring to bolster up snowfall totals even more. Much of the northern Midwest through portions of extreme upstate New York and extreme northern New England will experience only 75% of their average snowfall. This is due to the extreme cold that will be present that may push storms too far south to affect those areas too often.
Next, we will take a look at the precipitation outlook. Precipitation does not always fall as snow in the winter and here I take into account rain and ice as well, unlike the snowfall forecast which only predicted snowfall.
As you can tell the precipitation forecast follows the same general theme as the snowfall forecast with some slight differences. The area of above average precipitation is pushed further south compared to the snowfall forecast as I see the abundance of cold possibly shoving some storms too far south to hit northern areas. The 75% of average precipitation was also moved south from the snowfall forecast for the same reasons as stated prior. I expect this winter to be very wet over the south east while some areas further north may struggle to reach their averages.
Last but not least we have a full overview of how I expect the upcoming winter to play out.
Starting off in the blue I expect many cold records to be set along with a few minor-moderate snowfall events. When it does snow it will be very fluffy high ratio snow that will accumulate fast. There is a possibility of a major snowstorm if the trough does creep north once or twice during the winter but I would put those chances rather low at 33%. Saint Louis, Chicago. Cincinnati, Cleveland, Syracuse, and Bangor are all included.
In the red, I expect a big winter. A lot of snow with frequent cold shots. As I stated before this area could see multiple large-scale, high impact storms. Further south in the red area I see ice potential. With how cold I am forecasting it to be along with the expected storm track I could see a few storms overrunning cold air and producing an ice storm. Along I-95 cities such as Washington D.C., New York City and Boston I expect snowfall similar to the 2009-2010 winter. We may be talking about winter in this area for years to come.
In the pink, I am forecasting a winter battle zone. Here there will be plenty of mixed bag events. With so much cold I am expecting the possibility of one or multiple snow events in this area. Jackson, Atlanta and Savannah are all included here.
If you have any questions or comments please direct them to my twitter,