Increased warmth means more precipitation falls as rain instead of snow and causes what snow there is to melt earlier. (climatecentral.org)
In mountain regions that are warming, as most are, a larger fraction of precipitation falls as rain rather than as snow, which means lower stream flows in spring and summer. (thinkprogress.org)
One reason is because an increasing percentage of winter precipitation is falling as rain instead of snow in many locations. (wxshift.com)