As of 8 p.m this evening the zero degree line has pushed just about to the coastline. Wind chill readings are running 10 to 20 below zero and continuing to fall. This is going to be one of the coldest feeling nights in many years and although actual temperatures have been colder, the combination of wind and air temperature puts the hours between now and Sunday morning in the about as cold as it ever feels around here category.
Boston will likely have sub-zero readings for 10-12 hours. This is long enough to have frozen pipes in homes and businesses that typically have issues. Remember to let the water trickle just a bit to prevent frozen pipes.
The air is so cold and dense, if you are taking off from Logan Airport in the next 24 hours you might notice how quickly the plane is lifted off the ground. All the cold air makes planes actually lift easier, the opposite is true in the heat and humidity of mid-summer.
Morning Blog Discussion
The upcoming cold has been advertised almost as much as a snowstorm and you may wonder what the big deal is, but if you step outside from late Saturday afternoon through Sunday you’ll know why we’ve all been talking about it for the past week.
The good news about the arctic blast is it won’t last very long. By Monday afternoon, temperatures will feel nearly 60 degrees milder than just 36 hours earlier. That turnaround will be remarkable in itself.
The pool of cold air is like a big mass of dense molasses pushing its way southward on a very strong wind. If you have plans outside today the best time to do this will be before 1 p.m. along the coast and a few hours earlier across the far western areas of New England.
The map above shows temperatures early this afternoon. This is when the wind will start to howl. As the arctic front pushes through, you’ll hear and feel a strong gust of wind. At this point, temperatures will start to plummet quickly, losing 10 degrees in under an hour and a fully 20 degrees between early afternoon and mid evening.
Wind chill becomes a player in the forecast along the coastline as the sun goes down, but will already be at dangerous levels through the Berkshires. The graphic below really tells the story of the wind chill. You can almost feel it pushing towards greater Boston.
Winds will gust over 40 miles per hour, which could lead to scattered power outages. Some tree limbs might still be hanging precariously close to the power lines after the heavy wet snow a week ago. A strong gust of wind is all you need to take them down.
There are wind chill warnings for Saturday evening and Sunday morning. The combination of wind and cold will make frost bite on exposed skin likely if you are outside for longer than 15-30 minutes. Remember, this is on exposed skin. You can still go outside f you dress properly with a face mask, hat, and gloves.
It may seem obvious to most, but running in this kind of cold can be harmful if you have respiratory issues. Your lungs do better in warm, moist air. Breath through your nose, not your mouth, to allow the air to warm before it ends up in your lungs.
Temperatures Sunday morning will be cold even without the wind. The record in Boston is 3 degrees below zero. If Logan Airport reaches 4 below or less, we would not only have a new record, it would be the first February low temperature record since 1967. If Logan got to -8, it would the coldest morning since the 1950s!
Cold air is very dry. If you heat your house into the 60s tonight and tomorrow, the relative humidity of the air will be 2 to 4 percent. This is going to cause chapped lips, lots of static, and a generally dry feeling. This is a good time to have the humidifier going full blast.
Cold air is also heavier and denser than warm and moist air. While this may seem counter intuitive, it’s true. Check out the explanation from Hanby’s Hints. If you are a math person, this can be a fun exercise. It’s actually a good problem for school kids as well. What else are you going to do while it’s this cold anyway?
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