Along with the rains comes the danger of flash floods. The Virgin River that runs through the canyon usually has a current of 40 cubic feet/second at this time of the season. The night we arrived, the flow was measured at 2,000 cu ft/sec. We were hoping to hike The Narrows, where the canyon walls get very deep and close together, but the Rangers (and common sense) closed the Narrows on the day we were hiking in the Park. We did the Riverwalk which is the mile of paved trail that leads up to the Narrows. It was a great walk and we even saw a tarantula. Apparently this is the time they come out looking for a mate.