The United States Geological Survey’s water resource statistics for the last three decades show typical daily June flows for the Big Thompson River range from 89 to 251 cubic feet per second. In comparison, the Cache la Poudre, which drains a much larger watershed, generally carries anywhere from 560 to 910 cubic feet per second that time of year. But this year, late spring snows followed by a freakish heat wave and a week of unrelenting heavy rains triggered an unusually rapid and intense snowmelt that increased flows in both rivers to the heaviest recorded in 30 years. With the Big Thompson raging along at 1,500 cubic feet per second and the Poudre ripping through its namesake canyon at 4,500 cubic feet per second, you’d have to have been dumber than a box of hammers — or have a death wish — to even think about fly-fishing either of them.