Although the dry conditions in Iowa have been better since the beginning of November, they are still the worst they have been in a decade heading into winter, when there is limited opportunity to enhance soil moisture in preparation for the growth season of the next year.
The ground is typically frozen over during the winter months, which are also the driest. Additionally, the soil is more prone to freezing when it is dry.
In the case of winter droughts, according to State Climatologist Justin Glisan, “unless you get into a month like December of last year with the derecho and temperatures in the 70s — you will see some improvement from an anomalous event like that,” but overall, “you don’t really see a lot of change through the wintertime.”
But despite the fact that December of 2021 was one of the warmest Decembers on record, with temperatures across the state averaging nearly 7 degrees higher than normal, the drought did not significantly improve overall. According to Glisan’s meteorological summary for that month, although the derecho that occurred on December 15, 2021 caused more than 40 tornadoes and strong thunderstorms, the average precipitation across the state was around 40% lower than typical.
According to the data provided by the U.S. Drought Monitor, close to three quarters of the state is experiencing drought conditions of varying degrees. The conditions are the worst in the northwest region of the state of Iowa, where a patch of extreme and exceptional drought has spread throughout parts of 18 counties and where the agricultural yields of some areas are the lowest they have been anywhere in the state.
However, according to Aaron Saeugling, an Iowa State University Extension field agronomist in southwest Iowa, the state’s average corn yield is anticipated to be greater than 200 bushels per acre. This is a result of a wet spring as well as crop genetics that appear to be becoming increasingly resistant to moderate drought.
Monitoring of the soil at a university research farm in southwest Iowa indicated that the land is the driest it has been in 14 years; this may have an impact on the amount of crop that can be harvested the following year.
Recently, Saeugling stated that the area requires approximately 20 inches of rain.
When the United States Department of Agriculture (USDA) released the most recent crop status report of the year in late November, it stated that approximately 44 percent of the state had enough or surplus topsoil moisture for crop production. A little less than a third of the state’s subsoil had an acceptable amount of moisture.
According to that research, approximately 7 percent of the topsoil in northwest Iowa had an appropriate amount of moisture.
According to Glisan, it is difficult to make a prediction about how the current drought circumstances would effect the growing season in the following year. The National Weather Service projects that Iowa will continue to have dry conditions through at least the month of February.
According to what he had to say, “if we don’t get into a series of wetter months — abnormally wet months heading into the spring — we can definitely see drought worsen and spread.”
However, he made note of how rapidly circumstances might shift. In 2018, Iowa saw the second-wettest year on record, yet for several weeks, a portion of the state was in the midst of an intense drought.