They're familiar phrases, but Dick Sebrosky of Pasadena wants to know more: "When the weather forecast says partly sunny, does that mean more sun than clouds? Also, what is the difference between ... snow vs. snow showers?" The weather service uses either "partly cloudy" or "partly sunny" when opaque clouds cover three-eighths to five-eighths of the sky. The latter is preferred for daytime. "Snow" is, well, snow. A snow shower is "a short duration of light to moderate snowfall," with accumulations possible. "Flurries" never accumulate.