People think that's something new and tend to forget the past.
In august 2003 I was on a military field exercise in Roth, Germany.
We had around 41°C during the day and just a couple of days later it was freezing cold at night (6°C)
It was around this time:
Fun fact: the temperatures at night dropped below zero just three weeks later. The water in my flask was frozen.
The weather history never forgets, but people do.