What does ていた mean?

Question

I could not understand ていた right after 晴れ in the sentence below.

海岸に行った時、とてもよく晴れていたんです。

Answer 1

ていた doesn't mean anything on itself, because it's a part of conjugation:

• 晴れる{はれる} - the verb - which means roughly "to become clear" (as in clear weather).
• 晴れて{はれて} - verb's te-form
• て+いる - a grammar form for continuous action
• て+いた - continuous action in the past

Combined, 晴れていた means "it was sunny" or "the skies were clear".