I'm using HTU21D connected to arduino nano to measure temperature and humidity inside evaporating room which is located near equator. Just outside the room (outdoor, surrounded by tree but direct sunlight from above), I got the reading value at around 30 Celsius for temperature and 66% for humidity. When I put the system inside the room, after 1 hour I got the reading value at 67 Celsius for temperature and around 25% humidity, which is quite strange since the room was supposed to be humid. I keep the sensor inside the room. Several hours later around 5 PM, the temperature inside the room decreased to around 35 Celsius, but the humidity measurement increased to around 65%. I only open the door for short time, and the room is big enough so most of the air stay in the room when I open the door.
Is this normal? I don't think my code at fault here. Any help will be really appreciated. Thank you.