Why partly cloudy and not partly sunny ? I have a answer , whats yours ?

Question

You've see it and heard it - the weather report- today will be partlty cloudly.

Answer 1

Both terms are used.  Partly cloudy means more sun than clouds, partly sunny means more clouds than sun.

Answer 2

The history of meteorology is closely related to the history of radio communication because it is a century ago, when ships started carrying radios, that worldwide data could be gathered and weather maps drawn.

In order to gather data, they had to come with a standard format. In addition to pressure, temperature, wind direction and speed, weather reporting stations, either mobile or stationary, used a way to define the cloud coverage, which is still in used today in METAR and TAF, which are weather report and forecast for airmen. It goes like this.

CLEAR: No clouds

FEW: Less that 1/4 of sky coverage

SCATTERED: Between 1/4 and 1/2 sky coverage

BROKEN: Between 1/2 and 3/4 sky coverage

OVERCAST: Total sky coverage

It is probably that kind of terminology that leads the weatherman to talk today about "partly cloudy."

Answer 3

Well, that is one great question seeing that weather forecasters are constantly attempting to get our attention.  the reason is that the sky is overcast.

Answer 4

The sun is always there, but clouds come and go.  Telling people the sun is there isn't particularly helpful, whereas telling people there are clouds is.  That's why the expression puts a bias on clouds, even though the two you mentioned mean the same thing.