During the winter and summer months it can be useful to know the outside temperature at a glance by looking at a window thermometer. These are attached outside your window to give accurate readings.
When buying home window thermometer look for an easy to read model displaying temperature to tenths of a degree. Automatically displaying the days maximum and minimum temperatures is a nice feature. Some digital thermometers also display humidity. Ideally choose a thermometer where you don't have to press buttons to access minimums and maximums because it will be attached outside your window and it wouldn't be convenient to do so.