Less warming projected during heavy winter precipitation in the Cascades and Sierra Nevada

Local rates of warming from increased greenhouse gas concentrations can be different during heavy precipitation than during other times. This variable warming can influence precipitation extremes through the Clausius-Clapeyron relationship and modulate the rate of snowfall decline. Large ensembles of simulations from a regional climate model were used to project, with high signal-to-noise ratio, changes in the daily winter temperature versus precipitation intensity relationship from the contemporary period to a mid-21st century scenario over the Cascades and Sierra Nevada of the United States. Warming rates decreased with increasing precipitation intensity over all montane regions, with the strongest relationship in the northern Cascades (1.2 degrees C less warming at 100 mm day(-1) than at trace amounts). The relationship may be linked to the projected north Pacific meridional warming gradient, as the moisture of the largest precipitation events originates at lower latitudes where warming is less, though other factors may contribute.