Early spring climate forecast
BROOKINGS – What a difference a year makes. Statewide, March 2013 in South Dakota was cooler and wetter than a year ago, where extremely warm temperatures contributed to a record warm year nationally and eventual drought development in South Dakota.
“In general, all areas of the state struggled to reach average March temperatures,” said Laura Edwards, SDSU Extension Climate Field Specialist.
Referencing data from the National Weather Service’s Cooperative Observer Network, differences are evident between western and eastern parts of the state. Edwards says temperatures were up to 6 degrees below average in the west and 6 to 12 degrees below average in the east.
“This is in sharp contrast to last year, when March temperatures were 6 to 15 degrees or more above average,” Edwards said.
Many eastern locations had monthly average temperatures rank in the top ten coldest of any March on record.
Precipitation in the last month varied widely, noted Dennis Todey, SDSU Extension and State Climatologist.
“Most notably, the northwestern part of South Dakota was exceptionally dry, with total precipitation ranging from 0.05 inches to 0.70 inches,” said Todey.
A select number of localities benefited from rain or snowfall above average, but these were few and far between.
“Some notable wetter areas are western Pennington county, Grant and Deuel counties in the northeast, west of Sioux Falls in McCook county, and Todd and Tripp counties in the south central. Most of these areas were about one half inch above average precipitation for March,” Todey said.
Unfortunately, some of the precipitation fell on frozen ground – leading to rapid runoff for pond and dugout refill, but little soil moisture recharge.
Edwards says the outlook for early April calls for a continuation of cooler than average temperatures for most of the northeastern areas. Elsewhere, temperatures will gradually begin to warm to near-average levels for this time of year.
“However, April is notorious for big swings between cold and warm temperatures,” Edwards said.
In the northeast, a lot will depend on how long the snow cover takes to melt. A higher chance of above average precipitation is forecast for the first couple of weeks of the month, which covers all but the far northwestern part of South Dakota. She notes that some farmers are appearing anxious for the snow to melt, and the forecast for April may not be encouraging.
“In the northeastern counties, there are still quite a few snow-covered fields, despite the last few warm days,” said Edwards.
Most farmers in that area plan to plant corn around the third or fourth week of April, and soybeans in early to mid-May. The southern area farmers try to get into fields even earlier. Spring wheat planting has barely begun, but those activities will increase rapidly this month as well.
Soil temperatures are an important consideration for planting conditions, Todey says.
“Soil temperatures at 4-inch depth are above average over most of the western and far southern parts of the state. Temperatures are lagging in the snow covered areas of the northeast. The generally dry soils should warm rapidly once warmer conditions reach the state,” he said.
A cool spring has been good news for the state’s drought in eastern cropping areas, but dryness has degraded conditions in the northwest.
“As the wetter season approaches, some more drought relief is expected across most of the state,” said Todey. “The latest seasonal drought outlook shows likely improvement over the next three months in all areas except the southern tier of counties along the Nebraska border.”
Conditions should improve. But impacts of last year’s drought are going to carry over into the growing season in the way of limited soil moisture and drought impacts on rangeland.
To read more articles about South Dakota’s climate, visit http://www.iGrow.org.