Have you seen condensation on your windows- specifically during the summer?  The good news is what you’re seeing is absolutely normal.

Condensation on a window occurs when the surface of the window is cooler than the “dew point” temperature of air in contact with the window. Condensation can happen during the summer, when outside air is very humid and inside temperatures are kept relatively cool.  Summer condensation problems are mostly visual. Since outside window and building surfaces often get wet from rain, a little extra liquid water will not be detrimental. The condensation should disappear as outside air temperatures rise.  In cases where the inside temperature is below the outside temperature, a Low-E coating will allow the outside glass temperature to drop to about the same as that of an inefficient window. In cases where the outside air is colder than the inside temperature, a Low-E coating allows the outside glass to get even colder. Therefore, under the right conditions, windows with Low-E coatings can develop more summer condensation than inefficient windows.  Since we cannot control the outside dew point temperature (or relative humidity), the options for preventing summer window condensation problems are to warm the inside surface of the window as a way to warm the outside surface. Raising the thermostat setting is about the only option. Exterior shutters, shades or even trees can help reduce summer condensation problems as well.

Source: “Window Condensation.” Window Condensation. Retrieved from: http://www.rlcengineering.com/win_cond.htm