Forecast discussion: Boston has been seeing a roller coaster of temperatures over the last week. Just yesterday, the high temperatures were in the middle 50’s. By last night, the temperatures fell to 12 degrees. The high today only reached 16 degrees. This massive dome of Arctic air has now influenced almost 187 million people. Just to put it in perspective, Atlanta’s low was 6 degrees Tuesday morning. Anchorage, Alaska had a low of 27 degrees.
This cold dome of air will remain in place for at least 24 more hours. Tonight, clear skies and light winds will allow temperatures to fall into the middle single digits. Any wind this evening will make the temperature feel like 5 to 10 below to our bodies. Also, any moisture still on the road may become black ice. Our high temperatures will rebound on Wednesday, as we actually make it above 20 degrees.
By Wednesday night, the polar vortex that has encompassed the northern U.S. will begin to retreat. This will allow the jet stream to bring move northward, allowing for tropical air to advance into New England. It may feel balmy to us on Thursday, as temperatures come close to freezing. We will finally reach above freezing by Friday, with temperatures in the middle to upper 30’s.
As we head into the weekend, the mercury will go even further, as high temperatures reach the upper 40’s. A low pressure system over Canada will bring a cold front closer to the east coast. Southwest winds will also get moisture from the Gulf of Mexico, and help feed the frontal boundary. We will see some showers begin sometime Saturday morning, and the precipitation will get heavier throughout the afternoon and evening. You may want to keep a raincoat or poncho on you if you are heading to Foxboro for the Patriots-Colts playoff game.
The rain will taper to showers early Sunday morning, as the low moves off into Nova Scotia. We may see some sunshine before the daytime hours Sunday afternoon. However, a quick moving low pressure system forming over the Southeast U.S. will bring another round of precipitation for Monday morning. However, this system pushes through rather quickly, with showers ending by the end of the evening commute.
As we head into the last day of the extended forecast, a quick moving Alberta Clipper type system will try to push through Northern New England by Tuesday evening. This could mean the chance of some rain and/or snow showers, as colder air will begin to return to the region.
72 hour forecast:
Tonight: Clear skies and very cold with a low of 6. Wind chills will make it feel like 5 to 10 below zero.
Wednesday: Mostly sunny and warmer with a high of 21. Winds will come from the west-southwest at 12-15 mph. Wind chills will make it feel like 5 to 10 below zero.
Wednesday night: Partly cloudy with a low of 14. Winds will come from the west-southwest at 10-13 mph.
Thursday: Partly sunny and milder with a high of 29.
Thursday night: Partly cloudy with a low of 19.
Friday: Partly sunny with a high of 37.
Friday night: Mostly cloudy with a low of 28.
Saturday: Overcast with rain showers by mid-morning, with heavier rain by the evening. Highs 46-49, lows 38-41.
Sunday: Rain tapering to showers in the early morning, before all precipitation ends by mid- morning. Partly sunny skies expected before sunset. Highs 46-49, lows 33-36.
Monday: Showers/rain by mid-morning, before precipitation ends in the early evening. Highs 47-50, lows 35-38.
Tuesday: Increasing clouds through the afternoon, with possible rain/snow showers during the evening commute. Highs 43-46, lows 26-29.