Saturday, April 19, 2014
How about that wind? Wind chill readings are once again below zero and the warmest part of the day occurred several hours ago at midnight when temperatures were still in 20s. Since then, the mercury has been falling and is now in teens in all areas. Readings will continue to fall this morning, before leveling off and rising a couple of degrees this afternoon.
Updates to my forecast can be found on Twitter @growingwisdom. Please share any questions or weather observations.
If you were hoping for the wind to relax a bit today, think again. The wind going to continue for the next couple of days and doesn’t really relax until later Wednesday. Notice the image below which is a pictorial representation of the overall forecast.
The wind has been beneficial in one way. The roads and sidewalks have dried nicely during the night so ice isn’t a big problem. While this is the case, anytime you have temperatures fall from near 50F to the mid-teens you can encounter isolated icy patches while driving.
Not even close to record cold here
The chilly weather continues through Thursday morning. During the next couple of days highs will be well below average and nighttime lows will fall into the single numbers. I don’t expect widespread below zero temperatures for two reasons. First, and most importantly, the core of this cold air mass is staying to our west. Secondly, the change in snow cover texture impacts how cold we become overnight. Light, fluffy and newly fallen snow reflects heat much better than older, frozen and hard crusty snow. Since we have the latter there’s another reason we won’t be quite so cold.
You can see how many cities have tied or set new record low temperatures across the country so far today. More may be set before midnight.
As the cold air departs for Canada, our January Thaw begins. Starting Friday and continuing for several days, highs will break the freezing mark. By the weekend many of us will enjoy temperatures in the upper 30s to near 40. There could be some light rain or snow over the weekend, but not a storm. A return to colder, but not bitter cold will occur sometime during the middle of next week.
Polar Vortex: What is it?
The upper winds have become configured in such a way so they are bringing very cold air to the country. You have likely heard the term “polar vortex” this week. This meteorological phenomenon is simply a semi-permanent circulation of wind in the higher levels of the atmosphere. The circulation is normally found over the arctic region of the planet. (Also South Pole). This week, a piece of the polar vortex moved south and carried with it the bitter cold air much of the country is experiencing. The upper winds will reconfigure by the end of the week as the polar vortex retreats into Canada and our weather becomes milder. The map below shows the status of the polar vortex Monday as the cold air was pouring into the country.
David Epstein has been a meteorologist for more than 25 years. He spent 16 years in Boston and currently freelances at WGME13 in Portland.
In 2006, David founded GrowingWisdom.com, a business producing educational and marketing videos for the green industry. He currently is a professor at Framingham State College, teaches Jan Plan at Colby College and owns Bloomscapes Inc., a landscape design business.
David authored "Gardens Of New England" and his work has been published in Grolier's Science Annual for 10 years. He lives in South Natick, Mass., and has a summer home in Harpswell.