This is today's temperatures where I live. It was 19 C in the early morning and it will reach 40 C in the afternoon. I want to passively cool my room which faces north (away from the sun) and has another floor above, so it is decently insulated.
Is there a way to store the coldness of the night and use it for the day? I was thinking of filling (a lot of) used bottles with tap water and leave them outside at night, only to move them back to my room in the morning.