Windows in the attic very wet

Hi,

earlier this morning after getting up, I noticed that there was quite a lot of condensation on all the windows in the attic (4x floor-to-ceiling, 1x skylight). In the bedroom and bathroom (each on the east side), I found it quite a lot. The other two rooms also had some, but not as bad. On the ground floor, there was almost none. Really just minimal.

I haven't really noticed this much in the past years, like today or even in the last few days. Is this "normal"?

Thanks!

As a supplement, the rosette/cylinder on the front door (inside) was also very damp/wet.

How high are the temperature and the humidity? What kind of windows do you have?

Triple-glazed plastic windows. Outside around minus 10. In the bedroom about 20 degrees and around 60% humidity, for example. The other rooms upstairs about 22 degrees, humidity similar.

The keyword here is "dew point". The temperature of the window is so low that the humidity condenses on the glass. It would not be so nice if this happened on the wall, as that would be a breeding ground for mold spores. On the window: wipe away. Preferably also ventilate more frequently. 60% humidity in heated rooms is, in my opinion, (too) much.

Thanks first of all for the explanation. Currently, it is around 50% in the attic. What would be optimal? My hygrometer indicates it as "ok". Downstairs in the living room, it shows 45, with a smiling emoji.