A large ridge of high pressure will warm us up from the 40s on Friday to the low 50s by Christmas Monday. The ridge is flat enough to allow some level of cloudiness across the region throughout the next week, but it is substantial enough to keep us dry as well. Overnight lows will start out in the teens Friday morning before easing off to the 20s for the rest of the week.

Snowman Melting

Yesterday, I said that snow can heat up (and melt) by heat conduction…warm air directly touching the snow. But an even faster way is to heat objects by radiation (think microwave oven). When the sun’s rays hit the snow, the radiational energy is transferred directly into the snow without warming the air. It’s the same reason pavement gets much hotter than air on a sunny day. Radiational energy transfer is very efficient, and can melt snow much quicker than conduction. It would be even more efficient if you sprinkle a little dirt on the snow, since dark colors absorb radiational energy much better than light colors. That’s also why snow melts on dark pavement faster than grass. Once a little pavement is exposed, it heats up quickly.

 

 

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