SIOUX FALLS, S.D. (KELO) — We had such a nice start to the month in terms of highs, but it seems like Mother Nature is throwing a monkey wrench into our transition toward consistently warm weather.
While the first three days of May featured well above average temperatures throughout KELOLAND, a pretty large swing has taken place toward the cooler side of things. Gone are the 70s and 80s. In their place are now 50s & 60s. So, what’s causing this? A large and strong ridge over the Pacific is helping displace cooler temperatures via a deep trough over the eastern half of the United States.
While this air mass will certainly bring well below average temps for this time of year, it’s not the coldest we’ve ever been. Our record coldest high temperatures in early May range in the upper 30s to mid 40s, with the most recent example being a high of 40 degrees on May 4, 2013. The core of this cold air mass may be centered to the east toward the Northeast, but there is plenty of chilly air to go around by day and especially by night.
With lows in the low 30s on several occasions, frost headlines will likely be needed through the weekend, so heads up to any gardeners out there. As for when this cold air finally gets out of here…well, they do say that patience is a virtue