* August is a month: It's the eighth month of the year, not a single day.
* Personification gives human qualities to non-human things: We might say "the sun smiled down on us" or "the wind whispered secrets" - these are examples of personification.
* August doesn't have human qualities: While we might associate August with warm weather and sunshine, the month itself doesn't possess these traits in a way that would qualify as personification.
Perhaps you are thinking of a phrase like "August's sunny days" which could be considered a metaphor, but it's not personification.
