雨が降りだした

it started raining

→ 雨
phrase Rare #33,172
it started raining 降りだした means “started to fall” and indicates that the rain began at that moment.
JA: 家を出た途端、雨が降りだした。
EN: As soon as I left the house, it started raining.

私が家を出るとすぐ雨が降りだした

As soon as I left the house, it started to rain.

私が友人と公園を歩いている雨が降りだした

While I was walking in the park with a friend, it started to rain.

夕方近く雨が降りだした

It started raining toward evening.

私はちょうど出かけようとしていたすると雨が降りだした

I was just about to head out when it started raining.

私がちょうど出かけようとしていたとき雨が降りだした

Just as I was about to leave, it started to rain.