(NOTE: I am writing this thread for casual interest readers as well as more intensely interested fellow “weather geeks.” )
Many of you have already seen a couple of outlooks on the web, in social media and a Buffalo News article last week suggesting signs are somewhat ominous for this coming winter. The News article even included an AccuWeather prediction that the dreaded “Polar Vortex” would make an appearance sometime later in September, ahead of a wintrier than average winter.
Some of these predictions may pan out, some may not, some are from educated meteorologists, some are from uneducated friendly fakes whose work is much akin to astrologers (the Farmers Almanacs, whose methodology is based largely on nonsense), and some are from teenage children on social media who have learned just enough about weather to be dangerous.
Know this: seasonal outlooks are markedly different from 1 to 7 day weather forecasts. They operate on different timescales, they necessarily filter out the noise of quick moving fair weather systems and low pressure storm systems, and they paint a much more generalized picture of expected patterns. Their verification rates/track records are far less impressive than the accuracy of near term weather forecasts, and that is to be expected. Much of the time, the signals from nature are weak and poorly defined. Making a summer outlook, which gets less notice, can be even less successful because signals are even weaker as the warm weather season approaches.
One noteworthy exception in making a winter outlook would be the likely development of a truly Strong el nino, as was the case prior to the winter of 1997-98. That was a “super” el nino, and el ninos of that magnitude do correlate with warmer than average conditions across the northern tier of the U.S. and in much of the east. If such an el nino was expected this year, I would have some confidence in predicting a warmer than average winter for our region. But we are NOT expecting a strong el nino. Most models which deal with el nino and la nina are forecasting a weak el nino, with a small chance of a moderate el nino. Weak el ninos are not known to correlate with a warmer winter in the east in general and in our region in particular. So, THAT signal from nature is not as helpful a predictor as one might hope. No 2 el ninos are identical and neither are their impacts. There are many variables/changeable elements which can impact the strength and location of an el nino. As of this posting there is a high (65%) but shrinking probability that el nino conditions will develop by late summer/fall.
There are other variables which have predictability only out to 2 weeks, such as 2 oscillating patterns over the NW Atlantic out to Greenland and Iceland. These Atlantic oscillations can have a huge impact on weather in the east and in our region. But if we cannot confidently predict their status much beyond 2 weeks in advance, that makes winter outlooks even more uncertain. And other variables can impact the status of those variables–even something as obscure as how much snow falls in Siberia in the month of October may affect what position the polar jet stream takes during the winter, as well as the factor of how much arctic sea ice melts in the summer months.
I can go on with the enormous list of uncertain variables, but I’ll slow down here. Winter outlooks are difficult enough even in late October and early November, let alone in early August. In my lengthy experience (and that of other meteorologists), winter outlooks made during the summer months simply don’t work well. IF I were to lean toward one direction or the other, I’d reluctantly say that at this point I don’t see current signs which would lead to a much milder than average winter in our region. But that leaning can easily change by mid Autumn, and I wouldn’t make any plans based on it.
BOTTOM LINE: Any winter outlook you’re seeing now should probably be taken not just with a grain of salt, but probably the whole salt mine.