This week, additional rounds of rain and snow added to the ample precipitation received across the West since December 2022. Continued analysis of the effects of the season’s moisture resulted in continued improvements to long-term drought conditions in many parts in the West. California saw improvements to severe (D2) and moderate (D1) drought, as well as abnormal dryness (D0) along the central coast and in the San Joaquin Valley and southern California. National Weather Service offices in the area report extremely wet conditions. Water-year-to-date (WYTD) precipitation is 150% of normal or higher, and nearly every indicator shows improvement with all but the longest timescales (24-to-36-month precipitation) showing above-normal conditions.
Similarly, the season’s precipitation chipped away at long-term drought areas in southern Nevada (D2 and D3), parts of Utah (D2 and D3) and western New Mexico (D1, D2 and D3). Precipitation deficits, soil moisture and streamflow show recovery. Groundwater levels and reservoir storage, which takes longer to recover, however, remain low. Precipitation in the Pacific Northwest helped improve severe drought (D1) in western Idaho and abnormal dryness (D0) in southwest Montana. Precipitation indicators in these areas are wet out to 12 months. In the rest of the Northwest, recent precipitation wasn’t enough to warrant improvement. Moderate drought (D1) expanded in north central and northeast Oregon where WYTD precipitation, streamflow and soil moisture is low. The Oregon state climatologist notes that “This water year has been surprisingly dry across the state despite the near-normal snowpack. Approximately 70% of the state only has 75% of normal WYTD precipitation, and about 25% is below 50% of average.” In Montana, severe drought (D2) expanded in response to low snow accumulations and its effect on streamflow and soil moisture.
As a comparison, below is the Drought Monitor Map from the high-point of the four-year drought: