How to Hit the Salmon Fly Hatch on The Madison River
All of those other elements like weather, snowpack, stream flow and rain are things that we can watch to predict when the water is likely to climb to 55 degrees. On a big snowpack year, there will be cool water coming out of the mountains later into the season so the hatch will tend to happen later and last longer. High flows on dam fed rivers like the Madison river will keep the water cooler and delay the hatch. Lots of rain will have a similar effect and delay or prolong the hatch. However, the largest determinant of Madison River water temperature is the weather. Hot sunny days and warm nights are going to melt that mountain snow fast and warm the river in a hurry. When this happens, the river will warm quickly and the hatch will follow. Likewise, if it stays hot and the temperatures keep rising, the hatch will move up river quickly and may not last long. We always like a slow moving hatch that progresses up river gradually and gives the fish and anglers plenty of time to enjoy the salmon fly hatch.