The recent cold snap up here in Maryland was legit. We were below freezing for 14 days, 22 hours; from 10:30am Dec 25th to 8:30am Jan 9th. An incredible 358 hours. Here's the tally for the stretch:
25Dec H/L: 36.6°F/27.1°F; 26Dec: 28.2°F/15.1°F; 27Dec: 23.9°F/9.8°F; 28Dec: 18.7°F/9.5°F; 29Dec: 25.5°F/14.6°F; 30Dec: 29.8°F/11.1°F; 31Dec: 17.7°F/4.8°F; 01Jan: 19.1°F/4.7°F; 02Jan: 22.2°F/5.6°F; 03Jan: 29.1°F/15.1°F; 04Jan: 25.3°F/11.4°F; 05Jan: 14.1°F/4.1°F; 06Jan: 15.1°F/-0.4°F; 07Jan: 21.2°F/12.7°F; 08Jan: 31.1°F/13.8°F.
The Potomac froze completely over and was thick enough to withstand the last 3 days of above freezing temps including 66°F yesterday with an inch of rain falling as well. We went back below freezing at 4am today and will likely not see 32°F again until noon-ish on Friday, another 155 hours later. We commonly go below freezing here but it is uncommon to have highs below freezing for such extended stretches.
My wife and I bought a second place in Vermont last spring. When we went up there the week after Christmas, I registered -21°F on the car thermo on the drive up and we had multiple days where the high remained below 0°F. Maryland seemed downright balmy when we returned later in the week. I shoveled my MD driveway when it was 9°F with a light coat and no hat and was almost too warm. It’s amazing how quickly you acclimate to extreme cold or warm. My wife and daughters said the same thing about the heat when they were in Costa Rica for a few months two years ago.