The 2022–2023 snow season started off relatively active across the West, with a few modest storms bringing snow accumulations to the mountains in early November.
By the start of December, snow water equivalent (SWE) across much of the region was above normal. Starting in early December, several storm cycles brought moisture-laden families of atmospheric rivers to the West Coast. Most of the landfalls occurred in California. The strongest series of storms occurred steadily from December 27 through January 17.
By the end of January, SNOTEL sites across much of the Sierra Nevada, Great Basin, Utah, Arizona, and western Colorado were at >150% of normal SWE. Unlike the 2021–2022 water year, in which snowfall was abundant early in winter but scarce after early January, the storm train continued with another series of strong storms across the West from late February through mid-March.
By April 1, snowpack was above normal across nearly the entire West, with few areas of snow drought. In some parts of the Sierra Nevada, Great Basin, Utah, Arizona, and western Colorado, SWE reached 200%–300% of normal and, in certain locations, set records. The northern Pacific Northwest and northwestern Montana was on the periphery of the storm track during most of winter. In these areas, snow drought developed as snowmelt began, and summer drought conditions are developing or seem likely to develop.
