Is it permissible to combine prayers in the office in congregation due to a legitimate Sharia reason such as rain?

Combining two prayers due to rain was legislated to attain the reward of congregational prayer. For one who is not inconvenienced by going to the mosque, combining prayers is not legislated. The default is the obligation to perform each prayer at its prescribed time. The Permanent Committee has issued a fatwa stating that it is impermissible to combine prayers in the case of light rain if there is no valid reason, citing the Almighty's words: "Indeed, prayer has been decreed upon the believers at specified times." Ibn 'Uthaymeen mentioned that combining prayers is not a concession according to all scholars, and that Abu Hanifa's madhhab does not permit combining prayers at all, except at Arafat and Muzdalifah. If the excuse is established, combining prayers is preferable. If it is not established, or if there is doubt, then combining prayers is forbidden.