On November 30, 2019; I posted about the upcoming 2019/20 Winter Season; and while the anticipated pull back or mild spell is more prolonged than what I was originally thinking, I did close my post on November 30th stating: *** These highly amplified November patterns historically feature a pull back during much of December, before completely becoming established around Christmas or early January. *** As of January 9, 2020 temperatures across the Northeast / New England have been averaging above to well above normal, especially since the beginning of-the-month. But MUCH unlike the recent mild absent winters of 2001/02, 2011/12, & 2015/16; the Sun is completely reverse, NOT highly active in-terms of sunspot activity on the solar disk as was 2001/02 & 2011/12, and there is NO strong El Nino influencing Pacific basin-wide Sea Surface Temperatures (SST's) as was 2015/16. Both stated factors played a significant role in the complete absence of winter during the above stated years. However, the 2019/20 Winter Season is definitely delayed but NOT denied. The reason for the extended mild spell since mid-to-late December; is due to a strongly consolidated Polar Vortex (PV) over high northern latitudes of the Northern Hemisphere. The strong Polar Vortex (PV) keeps bonafide arctic air up over northern Canada / Alaska; where the core of winter has been truly experienced. As-a-result, mid-latitudes experience an enhanced west-to-east flow of the jet-stream with a mild Pacific influenced air mass and transient or short-lived shots of cold. Many winter seasons experienced this pattern building-up to a complete longwave weather pattern change that resulted in a highly memorable second half-of-winter. The winters that are very similar to this year in-respect to the Sun & overall longwave global weather pattern (MUCH unlike the complete absent winters stated above) are 2002/03, 2006/07, 2009/10, & 2014/15 - ALL noted winters experienced above to well above normal temperatures during mid-to-late December through early January before a complete longwave pattern CHANGE; that brought winter in with-a-punch in late January, but especially February & March!
Forecaster: Daniel Viens, establishing author of New England NAO.