The summer can be a very hot time, and this can affect your garage door. If the garage door opener sensor is in the direct path of the sun it can actually make the opener not work while the sun is directly shining on it. If this happens to you, just make sure to shade the sensor with your hand and it will work again.
Another issue that comes along with the summer heat is how much heat can sneak in through an open garage into your home. This can end up costing you a lot of money on your electric bill. Make a point not to open your garage door during the hottest parts of the day to ensure as little hot air gets in as possible.