considerable cloudiness(=mostly cloudy; в сводке погоды, как то: Thursday Night, Oct 15. Considerable cloudiness and chilly. Winds will be calm. Low: -1 °C.Realfeel®: 2 °C.Lavrin)
intermittent clouds(в сводке погоды – ещё "переменная облачность"; intermittent clouds (n) are clouds that come and go, are sporadic, or not continuous Lavrin)