The easiest way to see if it is air is to fill a glass, set it on the counter and see if it clears up in a few minutes. Sometimes in winter when your water arriving is very cold, it can contain more air in solution than when it is warmer. So it could simply be air bubbles coming out of solution as it warms up. Another issue that can cause water to be cloudy is pressure. If your outside lines are more pressurized than normal, pressure also traps more air in solution and when it gets depressurized when poured into your glass, the air comes back out of the solution.