Yesterday, Chicago got up to 15°C, not a record but also not what one would expect in December. Our forecast for the next week has the temperature drifting just below freezing Sunday night but otherwise staying above 0°C, which feels a lot more like late March than New Year's Eve.
It's a little unnerving. Don't forget, warm winter means warm lake means warm summer—even without the driving force of El Niño, which may not dissipate before June.
Not that I'm complaining. I'm just...nervous.