It's worth noting that some style guides, such as the Chicago Manual of Style, recommend capitalizing seasons when they are used as an adjective to describe a specific event or period, but not when they are used as a common noun.
The four seasons - winter, spring, summer, and autumn (or fall) - are common nouns and are not capitalized in most cases. For example:
Like any other word, if a season begins a sentence, it must be capitalized. " is coming." 2. Part of a Proper Name