Are these japanese sentences both correct?

Question

These are both supposed to have the same meaning (yesterday the weather was bad.) Are they both right?

1. 昨日、悪い天気だった。

2.昨日、悪かった天気だ。

Also, should I have added は to the end of 昨日?

Answer 1

Yesterday, the weather was bad.

Kino, tenki wa warukatta desu.

昨日、天気は悪かったです。

You conjugate the adjective, not the verb in this case.

Answer 2

1st is good.

but more better sentence is follow.

　昨日は、悪い天気だった。

2nd ,correct phrase is follow.

　昨日は、天気が悪かった。

your ex. english sentence's case, corrcet sentence is follow.

　昨日の天気は、悪かった。