4 below zero, that’s the new record established this morning in Caribou, Maine. Not only was this a record for today, it also set a new benchmark chill for the month of April. Now, certainly Caribou isn’t close to Boston, you’d need to drive about 400 miles to get there. If you went the same distance south you’d be approaching Washington, DC where the cherry blossoms are already dropping. However, it’s still New England and an exclamation to a brutal winter.
The cold over northern Maine also illustrates just how dense cold air is and how, in the right pattern, arctic air can still enter the United States even nearly a week into April. Here in southern New England we did see freezing temperatures in many areas earlier.
Part of me likes the frozen ground early in the morning because the mud doesn’t get all over me or the dog, but I am ready to stop seeing deep cold. I know we still have several more weeks of frosts, however in the immediate Boston area the chances of a below 32F morning are rapidly decreasing.
Outside the city it will be late April through early May before the chances of frost are gone. There are even areas outside Route 495 that could see a frost after May 15th, but these are the exception.
This is going to be a chilly week with a couple of periods of rain and perhaps even some wet snow or sleet. 33 years ago we were experiencing a very unusual April nor’easter with deep cold and deep snow. April snowstorms are atypical and many years we see little or no snow. However, as is indicative by the cold air to our north this morning, a full-fledged winter snowstorm is possible, even in April.
The reason for the unsettled conditions this week is a stalled out frontal system dividing the cold winter air from the milder spring temperatures. This type of pattern might not occur every year, but it’s quite common. Because of the heavy dense nature of the cold air and the cold ocean temperatures this time of year, the warmer air has a hard time moving north. Eventually, the warm air wins, but in years with long winters, the chilly pattern can last well into May.
Small waves of low pressure will ride the temperature boundary over the next several days. The rain tomorrow could change to snow or sleet before ending Wednesday. Another round of rain will affect the region on Friday.
Today is game 1 of the official season for the Red Sox. They are playing down in Philly where it won’t be very warm and there is a chance of showers. The future radar loop below shows showers moving through that area this afternoon, but not a widespread period of steady or heavy rain.
After some rain Friday, there are signs of milder air returning later in the weekend. I think Sunday appears to be the better of the two weekend days.