Summary: October 1, 2019
Water Year 2019 ended in an unfortunate whimper. What started out with a bang (cooler than average temperatures, above average snow, wet spring into early summer) shifted to hot and dry conditions for much of the Intermountain West, ending with an underperforming monsoon season.
The result of this sudden shift is evident in SPIs, where short-term out to 120 days are very negative for the southern half of the IMW, and then positive on the longer timescales for most of the IMW. Wyoming has fared the best, with closer to average conditions throughout the water year. New Mexico has struggled the most.
The hydrology of the region still holds up, with streamflows near average and water supplies in good condition. Rainfall fed agriculture this summer has struggled, but irrigated ag has been fine and winter crops did well. Short-term indicators such as soil moisture and evaporative demand show the stress in the region, and reports of struggling corn crops support those indicators.
The outlook points to more dry conditions over the next two weeks. Temperatures will be more seasonal this week, but a return to the warmer than average pattern is probable after that.