As we enter the new year and a new decade, we do so with a January forecast well-above normal. I’m not sure what normal actually is these days around here, but by the book, we normally have highs of 63F and lows of 43F in this month. Already, the 30-day climate forecast is looking for ABOVE normal temps:
Last year, our lowest January temp was 30F on the 24th, but the year before we dropped to 19F on the 17th and 2018′s January recorded ten days below freezing. So it does get chilly around here. In 2017, we fell to 21F on January 7th, down to 32F in 2016 a couple of times, and to 28F on January 8, 2015.
Not this year. For at least the next 16 days, I have above-normal temps and certainly through next week:
So what’s behind all of this? Well, in a phrase, the "Polar Vortex”. The PV is strong right now and forecast to stay that way. "Strong” means that the jet stream winds at the North Pole are fast which trap the cold air. There are fluctuations (often caused by warmer air invading from the Pacific) which cause the PV to weaken, allowing the cold air to slip south toward the USA, but that doesn’t look to be happening anytime soon. Here’s a graphic illustrating the Polar Vortex. Currently the left side of the graphic is what is going on:
One last note: a mild January does NOT foretell a mild February. All it takes is a little weakening of the Polar Vortex to send a rush of arctic air our way. Mix that with a little precip and you have an ice storm in the making. Don’t put the parkas back in the attic until at least spring break!