Nebraska is no stranger to extreme weather conditions, especially during the winter months. Sept. 22 marked the start of meteorological fall in the United States. Most of the country, including Nebraska, has seen above average temperatures, but that might not continue once Old Man Winter takes hold.
Current temperature and precipitation forecasts from the Climate Prediction Center, show Nebraska has an equal chance of seeing above average or below average temperatures and above average or below average precipitation. This means that things could go both ways at this point.
However, the CPC has issued a La Niña Advisory stating that “La Niña conditions are present and are likely to continue through the Northern Hemisphere winter.”
So what is La Niña, and how does it affect our winters in Nebraska?
“La Niña is an oceanic phenomenon in the equatorial Pacific Ocean,” said Qi Hu, Ph.D., an earth and atmospheric science professor at the University of Nebraska-Lincoln. “During a La Nina, the SST (sea surface temperature) in the eastern equatorial Pacific is colder than its normal temperature, and the SST in the western equatorial Pacific is warmer than its average.”
Hu said the upcoming winter in Nebraska will be slightly drier than average. However, he said there is little reliable evidence to suggest that La Nina impacts precipitation levels across the state.
“There are studies claiming some effects,” based on limited data, according to Hu.
With drier conditions a possibility, Nebraska may dodge spring flooding.
In March, 2019 Nebraska was hit with a “bomb cyclone,” which caused rapid snowmelt, leading rivers to rise across the state’s central and eastern parts. According to a federal report, rapid snowmelt, combined with heavy rainfall, led to over $2.6 billion in damage and killed five people.
“The 2019 spring flood that devastated northeastern Nebraska was a result of a sequence of special weather anomalies from late January to late March of 2019,” Hu said.
“I think the probability for the same situation to occur in the spring of 2021 is low,” he said.
For more information, visit www.ready.gov.