Manufacturers package instructions with strips that include information on their use during spells of unusual heat and humidity. Some manufacturers recommend storing strips in a dry place at room temperature, between about 68 to 86 degrees F. (This may preclude the bathroom.) Some advise against storing in the refrigerator. Those that allow refrigeration may state that strips should be brought to room temperature before using.
If you've recently weathered a storm, power outage, or other situation that exposed your strips to extreme conditions, refer to the instructions packaged with your strips. It wouldn't be a bad idea to run a control solution or control strip through your meter as a test.