What is the difference between partly sunny and partly cloudy?

Twice today I was asked about the difference between partly cloudy and partly sunny.   And that inquiry is one of the most frequent I get, for reasons I do not understand.

OK...let's settle this for once and for all.

Here is an image of a partly cloudy sky:


And here is an image of a partly sunny sky:


They are the same..... during the day, partly cloudy and partly sunny denote exactly the same thing:  a sky with between 3/8 and 5/8 coverage of clouds.   Obviously, partly cloudy would be a better choice at night.

Mostly cloudy  is 5/8 to 7/8 coverage, while mostly sunny indicates 1/8 to 3/8 coverage during the day.

Now, a harder one.   What does it mean to have a sky obscured?   Is it the same as an overcast sky?

The answer to the second question is NO--they are not the same.

The sky is obscured when you can not see the sky, when you are in middle of cloud or smoke or dust storm.  Here are two examples of an obscured sky, one from smoke and the other from low clouds/fog:




An overcast sky is when the entire sky is covered by clouds or smoke, but you are not in them.  You can see the base (bottom part) of the clouds or smoke.  Here is an example:


With this knowledge, you can amaze your friends at the next cocktail party.... whenever cocktail parties start again. 


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