Cooler than average temperatures are expected to continue across the northern states in May, according to a recent report released by the National Oceanic and Atmospheric Administration's Climate Prediction Center.

According to the report, states including Montana, North Dakota and the northern Great Lakes states are most likely to experience cooler than average conditions through May.

"The area that is most likely to continue the cool trend will skirt northern South Dakota," said Laura Edwards, SDSU Extension climate field specialist. 

"The pattern we have seen this winter has been a strong ridge of high pressure over the western states, and a trough bringing wetter and cooler conditions to the eastern United States," she said. "This pattern will gradually break down as we move into the summer season."

Currently, there is some discrepancy among the numerous climate computer models for precipitation in May, she added. "Some models indicate wetter than average, while others show near normal for the coming month. The official Climate Prediction Center report states equal chances of below average, near average, and above average for May," Edwards said.

Area farmers and gardeners have been eagerly awaiting warmer weather this spring, as soil temperatures are still too cool in many areas to plant corn and backyard gardens. Small grains, such as wheat and oats, are able to tolerate the cooler soil temperatures that currently measure in the 40 Fahrenheit to 50 Fahrenheit range at four-inch depth. Soils are still frozen at deeper levels, as the maximum frozen depths reached several feet below the surface this winter.

"We've seen quite a bit of preparation activity in the fields in the southern and central parts of the state (South Dakota), but activity has been relatively quiet in the north and northeastern counties," Edwards said. "The below freezing temperatures this week, and three to six inches of snow that fell April 16 in Codington, Grant and Deuel counties will likely further slow planting progress."

The climate outlook for the next three months shows Montana and North Dakota to remain in an area of cooler than average temperatures. 

"South Dakota is just south of this region, with equal chances of below average, near average, and above average temperatures expected through July," said Dennis Todey, SDSU Extension state climatologist.  

Todey added that precipitation can be a challenge to forecast for the early summer season, as thunderstorm activity is more likely, and climate computer models are less reliable.

"There is not much concern at this time for an extreme drought to develop this summer," Todey said. "As we move into the wetter spring and summer season, our drier top soil could recover quickly."

One factor that could affect our summer conditions is El Niño, added Todey. "During the growing season, El Niño often means wetter and cooler conditions in the Corn Belt," he said. "The most recent indicators show El Niño to be increasingly likely to develop in the summer season."