The providential rain came just as we were worried about continuing the wedding without umbrellas.

providential 是由名词 providence（天意、天命）加上形容词后缀 -ial 构成的形容词。providence 来自拉丁语，原指"神的预见和安排"。 providential 形容某事"像是上天安排的、及时出现的"，常用来描述在关键时刻恰好发生的幸运事件。