2009-2010 Winter Forecast

The Winter Forecast



Winter can be quite tricky here in the Twin Tiers.  We can see anything from rain to snow, ice to cold, and mid-winter warm-ups.

In the past 3 years, snow fall in the Twin Tiers has been slightly below average. In the last 2 years, Mother Nature has not produced a significant snowfall over a foot. But, it has been colder. After a very warm winter in 2006-2007, temperatures shifted back to reality with two average to slightly below average winters.



My forecast for this upcoming winter indicates that we’ll have 80-90 inches of snow, which is slightly above average. Temperatures will be about 3 degrees colder than average. I'll go one step further and give a month by month breakdown.



First the snow. December should be about 5 inches shy of the monthly average of 17 inches, while January and February will be above average with ancitipcated snowfall at 30 inches and 25 inches respectively. Temperatures will be average, around 27 degrees for December. January will be 2 degrees below its average of 22 degrees. February will also be a below average month by about one degree.



A number of factors have gone into putting the pieces of this forecast puzzle together. Below you will find the factors, with more detailed information.



Atlantic Multidecadal Oscillation (AMO)



This describes the temperature changes of the water in the North Atlantic Ocean over a long period of time. There are cool phases and warm phases, which may last 20-40 years. We know this oscillation to have occurred for at least the last 1,000 years. Currently we are in the warm phase of the AMO, and have been since 1995. While forecasting a switch between phases isn’t possible at this time, we have noticed patterns in the weather that are different between the warm and cold phases. There is an increase in the number of Atlantic hurricanes, but for us it means that we see more snowfall.



On average we see 90 inches of snow during a positive phase of the AMO, while during a negative phase, we see around 80 inches. Average snowfall for the Binghamton Airport is 80 inches.



I did some additional calculations and found that 76% of the years in the positive (warm) AMO phase had snowfall that was 75 inches or greater, while only 56% of the years in the negative (cold) AMO phase had 75 inches or greater. During negative (cold) phases of the AMO, 72% of the years had 85 inches or less, while the positive (warm) phases of the AMO 48% of the years had 85 inches or less. I performed these calculations because quite a few years fell just below or just above the average.



North Atlantic Oscillation



The AMO can also cause a primarily negative phase of the North Atlantic Oscillation (NAO). This would result in a colder and snowier environment for the northeast. The North Atlantic Oscillation is simply the changes in strength of subtropical highs (Central Atlantic) and polar lows (North Atlantic) in the Atlantic. A stronger subtropical high, and a stronger than normal low gives us a positive phase. In the positive phase, we usually see warmer and wetter winters. A weaker subtropical high and a weak polar low gives us the negative phase. In the negative phase, we usually see colder and snowier winters. So overall, this gave some weight to a colder and snowier winter.



El Nino



I also looked into the effects El Nino has here in our area. El Nino is the warming of the waters in the equatorial Pacific Ocean. Presently we are in a moderate El Nino phase.

Weak El Nino’s have led to significantly colder and snowier winters. Moderate El Nino’s have led to average cold, and near average snowfall, while strong El Nino’s have cause warmer than average temperatures and slightly below average snowfall.

At this time it appears that the El Nino phase will continue through the winter. I believe the temperatures in the equatorial Pacific will peak sometime within the next 3 weeks or so, before decreasing. Once the decrease begins, I believe the weather patterns will follow a colder and snowier scenario. This is why I forecasted below average snowfall and average temperatures during the month of December.



Climate Models



I also looked at one some climate models available on the web. Overall the model consensus was toward average to below average temperatures, and average to above average snowfall.



Snowfall In Canada & Siberia



Snowfall over Canada and Siberia during the late fall months can also be a useful tool to help forecast the upcoming winter. At this time snowfall is average to above average. This would also support my colder and snowier than average winter.



Solar Cycles & Energy



The inactive solar cycle may also have some influence on our winter as well. We remain in the deepest solar minimum in the last 100 years. Less output from the sun equals less heat and thus a chance at cooler temperatures.



There are so many other factors that could be discussed and used to piece the puzzle together. Some factors I have yet to learn about as new information and studies continue to be produced by the meteorological community. I’m looking forward to learning more about seasonal forecasting in the future and to the winter ahead.