Cool temps, frost hit Mitchell
It was a frosty Thursday morning in Mitchell as the temperature fell below freezing for the first time since late April.
The low temperature Thursday morning in Mitchell was 27 degrees, according to Phil Schumacher, a meteorologist with the National Weather Service in Sioux Falls. That's only 2 degrees shy of Mitchell's record low for May 15, which was set at 25 degrees in 1959.
The low in Mitchell has dropped to 32 degrees twice in recent weeks, on May 5 and April 22, but hasn't dipped below freezing since hitting 31 degrees April 20. It's unusual, but not unheard of, for temperatures to fall this low this time of year, Schumacher said.
A record low temperature of 23 degrees was reached Thursday morning in Aberdeen, breaking the old record of 24 degrees set in 1959.
The reason for the colder-than-normal temperatures, Schumacher said, is the air still sweeping into the region from Canada.
"As a result it's been cool, but it's also been dry," he said Thursday afternoon. "When you get a clear night like last night, the temperatures can really fall."
The weather service forecast a low of 32 degrees for Thursday night in Mitchell. Areas of widespread frost are expected to develop early this morning in much of South Dakota east of the Missouri River, Schumacher said.
On Thursday afternoon, the weather service issued a freeze warning for much of eastern South Dakota, including Mitchell, which was to be in effect from 3 to 8 a.m. today.
The temperature is expected to reach a high of 60 degrees today, with slightly warmer weather forecast this weekend. The highs Saturday and Sunday are forecast at 66 and 69 degrees, with a chance of thunderstorms Sunday night into Monday morning.
Nathan Mueller, an agronomist with South Dakota State University Extension, said the crop most at risk in the recent cold temperatures is most likely alfalfa hay. If temperatures fall to the low 20s, as they did Thursday in Aberdeen, the damage to the hay could be significant.
"If it gets really cold for long enough, it can just kill the plant tissue all the way to the ground," Mueller said.
In 2013, South Dakota tied Montana for most acres of alfalfa hay harvested in the U.S. Both states harvested approximately 1.8 million acres of alfalfa hay, according to a U.S. Department Only 4 percent of corn planted so far this year in South Dakota has emerged, according to the USDA. That will limit the harm the freezing temperatures will have on the crop, Mueller said.