What should I do if I missed the Dhuhr and Asr prayers combined at the mosque due to rain; should I pray them combined alone or with another congregation?

The prescribed way is for the five daily prayers to be performed in congregation in mosques. However, it is permissible to combine prayers in the mosque due to rain or similar excuses that cause hardship and difficulty, so that they may be prayed in congregation, not individually. If a worshipper misses the congregation because he arrives after the prayer has concluded, it is not permissible for him to combine the prayers if he will be praying individually, because the reason for combining prayers—which is to preserve the congregation and remove hardship—is no longer present. In such a case, he should pray each prayer at its appointed time.