Climate outlook predicts cool temps will linger into spring
BROOKINGS, S.D. – The unusually cold temperatures that have held their grip over South Dakota are expected to continue into March, according to the latest climate outlook released February 21, 2019.
“Following an exceptional cold snap in January, temperatures throughout the state have remained 8 to 20 degrees below average, setting several single day records, with some areas of the state on track to rank February 2019 the coldest on record,” said Laura Edwards, SDSU Extension State Climatologist.
Edwards said the cold climate pattern is likely to continue into early or mid-March at least.
“This pattern tilts the odds towards colder than average temperatures overall for the month ahead,” Edwards said, pointing to the National Oceanic Atmospheric Administration (NOAA) Climate Prediction Center’s outlook for March 2019.
“Most of the north central and Great Plains states are favored for colder than average temperatures,” Edwards said.
Below average temperatures, above average snowfall
After a relatively warm and dry start to the winter season, several small snowstorms have accumulated snow on the ground throughout February. “Many locations across the state have already measured more snow than they receive in an average year. To date, snowfall approaching 50 inches in some northern and northeastern areas,” Edwards said.
Despite the wet weather pattern that has defined February, looking ahead to March, there is some uncertainty in the outlook.
“There is some indication that in early March this wet pattern will subside and turn drier. Unfortunately, there is not a lot of confidence in the latter part of the month. As a result, there are equal chances for wetter, drier or near average precipitation,” Edwards explained.
Flood potential this spring
Looking to spring, Edwards said many are concerned by flood potential.
“The southeastern part of the state is holding a lot of moisture from 2018 in the soils, sitting in fields and ditches. Even if we experienced average winter precipitation, this region of the state is likely to flood again this spring when snowpack melts,” Edwards said.
In the northeast and east central regions of the state, measurements show 4 to 8-inches of moisture currently held in the snowpack.
Ideally, Edwards said temperatures above freezing in the daytime and below freezing at night would allow snow to melt and ground to thaw gradually. “However, the longer we hold onto cold temperatures, the more likely these ideal conditions will not occur. It is more likely that we will have a rapid warm up when spring temperatures do arrive, which suggests much of eastern South Dakota will see some minor to moderate flooding in the James, Vermilion and Big Sioux River Valleys.”
The National Weather Service and U.S. Army Corps of Engineers are keeping a close eye on snowpack conditions throughout the Missouri River system and will be issuing flood updates as the snowmelt season begins.
Spring moisture is good news for those in western South Dakota who rely on snowmelt for pasture, range and forage production. “It is optimistic for a good start for grasses and forages to grow this grazing season,” Edwards said. “Snowmelt and rain can also help fill stock ponds as cattle are turned out to graze.”
Currently no area of the state is experiencing abnormally dry or drought conditions.