The National Oceanic Atmospheric Administration’s (NOAA) Climate Prediction Center officially declared a La Niсa Advisory back in November. “This means that La Niсa conditions are observed and expected to continue,” said Laura Edwards, South Dakota State University Extension state climatologist.
NOAA observes La Niсa conditions using sea surface temperatures in the Pacific Ocean, Edwards explained. “For La Niсa, ocean temperatures are cooler than average near the equator in the Pacific Ocean, which can alter jet streams and storm tracks,” she said.
“There are varying strengths of La Niсa, from weak to strong. Overall the colder temperatures are fairly consistent in any La Niсa winter,” Edwards said. “What is more variable is snowfall.”
In weak La Niсa events, there has historically been above average snowfall in the Northern Plains states. In strong La Niсa events, this is not usually the case.
For our winter season ahead, Edwards said a weak La Niсa is expected. “Thus the climate outlook shows an increased chance of above-average precipitation,” she explained.
This potential increase in snowfall is more likely to occur in mid- to late winter, or around January and February of 2018.
This cold, and possibly wet, climate outlook may create challenges for livestock producers who have already struggled with drought losses in pastures and forage.
“One way that animals adapt to severe cold is to increase their feed intake, which is already a challenge in some areas,” Edwards said.
Shelter and protection from severe cold and some increased snowpack amounts may need to be considered as well.
Winter wheat growers may take some solace in the potential for increased snowfall, as this can insulate the crop in harsh cold temperatures. Also, increased snowfall can provide some soil moisture in the spring when it comes out of dormancy. — South Dakota State University Extension
