As we look at March in the rear-view mirror, we look ahead to April and the potential for rain to return to South Dakota to reduce drought concerns across the state.
March in Review
March was much warmer than average, with the northern and eastern regions ranking in the top ten percent of warmest Marches on record (since 1895). In the southwest corner of South Dakota, temperatures were near average. In the opposite corner of the state, in the northeast, temperatures were more than ten degrees above average for the month.
The very warm climate combined with very dry conditions to make drought worse in the northwest and north central regions. Some locations, such as Lemmon, South Dakota, reported zero measurable precipitation for the entire month. Drought conditions slightly improved across the southern border, as some snow and rain fell across the South Dakota-Nebraska border in the middle of March. By the end of the month, 78% of the state was in drought.
April began with record warm temperatures over Easter weekend. For the rest of the month, warmer than average temperatures are more likely than cooler temperatures (Figure 1).
An active, wetter weather pattern is beginning in the first full week of the month, but it is not likely to hold for all of April. The National Oceanic and Atmospheric Administration (NOAA) Climate Prediction Center’s precipitation outlook for April has the odds leaning towards a wetter than average month in the northeast corner of the state, while the odds are slightly towards drier than average in the far southwest. At the time when that outlook was published, the wet period in the middle of the month was becoming clearer, but the end of the month was less clear.
The combination of warmer than average temperatures, even with near-normal precipitation, is not likely to be enough to significantly improve drought conditions in April. A longer duration wet period would be needed to overcome the evaporative demand from the soils and landscape and the water needs of early grass and crop growth that are responding to record-warm temperatures.
Soil moisture is currently about 20% to 50% below this time last year, and five to ten percent below average for this critical time of year, which is enough to create concern about severe drought. Shallow soil temperatures reached the mid-to-upper 50s in degrees Fahrenheit on April 5, which is another indicator that soils are dry and warming rapidly with high air temperatures.
April climate conditions are critical to starting the growing season off on the right foot. Temperature and precipitation will be essential to track in the coming weeks, and decisions should be made early this spring in response to drought conditions. There is limited soil moisture in reserve should a prolonged summertime drought set in, and drought conditions are worsening in some of our neighboring states. Supplies of water, hay and other feed sources may become limited across the region.
Keep in touch with updates from SDSU Extension on our drought page for additional resources and information this growing season.