That hard freeze overnight has cemented the snow-and-ice cover and lacquered some of the roads with black ice.
More snow is possible this weekend – but no mega-storm, for now – but melting is occurring, albeit glacially.
The below-freezing temperatures belie the fact that the sun is rapidly gaining steam.
February is the No. 1 month for solar-energy gain, according to Drexel University’s Fred House, a specialist in the earth’s radiation budget.
He has calculated that on average throughout the year, the sum beams 329 watts per square meter to the top of the Earth's atmosphere above Philadelphia.
That low point is 156 watts, at the winter solstice, reaching a high of 484 watts at its summer counterpart.
In February, the wattage increases from 208 watts on Feb. 1 to 280 at the end of the month, beating the average daily rate by 60 percent.
The melting is going to be slow because the snow-and-ice cover is densely packed with frozen liquid.