What is the difference between partly cloudy and mostly sunny? or Partly sunny/mostly cloudy?

Question

Aren't they the same?

Answer 1

Very subtle differences that are barely noticeable.

Sunny/Mainly clear - < 10% cloud cover

Mostly sunny - 10-30% cloud cover approx

Partly cloudy - 30-50% cloud cover approx

Partly sunny - 50-70% cloud cover approx

Mostly cloudy - 70-90% cloud cover approx

Cloudy - > 90%

Answer 2

Sunny - mostly clear skies

Mostly sunny - some clouds.

Partly sunny  - some sun

Cloudy - basically overcast

Mostly cloudy - some sun

Partly cloudy.  - a few clouds

Answer 3

No.  Partly cloudy and mostly sunny means that for the majority of the day it will be sunny, whereas partly sunny and mostly cloudy means that the majority of the day it will be sunny.