Mold Growth in Different Temperatures

I doubt what you describe would cause mold. By far, the biggest factor in mold growth is the sustained presence of water. If you have a poorly ventilated area that gets moisture, you can start to grow mold. If you don't have this, the temperature doesn't matter all that much. I don't know where you live, but good air circulation is usually good for preventing mold (since it keeps water from collecting on surfaces). Assuming the inside is warmer than the outside air, letting outside air in should keep the humidity inside down.