An hour later after borrowing all the tarps and plastic we could find, working in gale force winds, with lumber scraps, & all the buckets at our disposal filled with rock, bricks, & stepping stones, it's sort of tarped. So it's back out tomorrow with a contractor and some sort of plan. (5 gallons of wet/dry mastic?)
It's a small leak, but right through some of the fine woodwork. The dehumidifier is running.