On August 31 , Katrina was absorbed by a frontal boundary and became a powerful extratropical low , causing 1.97-6 .69 inches ( 50-170 mm ) of rain in 12 hours , as well as gale-force wind gusts from 31 to 61 mph ( 50 to 98 km\/h ) in southeastern Quebec and northern New Brunswick .
On August 31 , it was absorbed by a frontal boundary and became a powerful extratropical low , causing 1.97-6 .69 inches ( 50-170 mm ) of rain in 12 hours .