okay…so i was watching the weather the other night and the forecaster mentioned partly cloudy skies ahead…then a few minutes later on another channel a forecaster predicted partly sunny skies ahead…so my question is, what is the difference?..is it that one forecaster is more optimistic than the other?..
I think you’ve just answered your own question there, dahempfaerie. I don’t think there is any real difference – just different schools of thought.
Now, is my glass half full over there, or … ?
well, that’s the only thing i can think…
According to this page, the Official Definitions, as provided by the National Weather Service, are that “Partly Sunny” refers to “3/8 to 5/8 opaque [an observer can not see through the clouds; the sun, moon , stars, and blue sky are hidden] clouds”, whereas “Partly Cloudy” refers to the same condition as “Partly Sunny”…when it’s night.
Well, that’s logical enough.
However, according to this page (from the Geophysical Institute at the University of Alaska at Fairbanks) “…if there had been a streak of really lousy weather at the time of the forecast, but it looked like it might be clearing up, the nod went to ‘partly sunny.’ On the other hand, if it had been nice but it looked like some clouds would be showing up in the evening, the outlook was for ‘partly cloudy.’”
What your local weather guy means by the terms may be something else entirely.
nice research…thanks, man
My meterologist always has the same forecast: “Clear to partly cloudy with possibility of precipitation.”
So far, she’s been right on the money!
We’re almost always “partly cloudy” here, anyway. Comes from livin’ in the Land of The Long White Cloud. 
You need to move down to Central Otago Ice Wolf, lots of clear blue days there.
Of course, it can be a little cool over the winter months
“Tonight there will be partial darkness, with a chance of light in the morning hours…”
A pesimist says the glass is half empty…
An optimist says the glass is half full…
A housewife says “Well somebody has to wash this damn glass!”
[random thoughts to ponder as I wonder yonder]