Dear 100 Hour Board,
What's the difference between "mostly cloudy" and "partly sunny" in reference to weather reports? Is it just the weather people trying to be optimistic, or is there actually some percentage of blue skies that warrants the different titles?
There is no difference between the two terms. Technically, "partly sunny" has no defined meaning in meteorology. You just have forecasters looking at the glass as 25% full rather than 75% empty.