"This ward should last another... Just under twenty-two hours. If the storm hasn't abated by then, I can renew it. If we are all intent on staying here, I'm going to set up additional spells to ensure our privacy." With that, the wizard pulled out his spellbook and began studying it intently again.

Spoiler
Show

Unless someone interrupts, he will prepare and cast Alarm and Mage's Private Sanctum with vacant spell slots, also centered on the altar. Afterwards, he will rest for eight hours.