It’s felt unusually hot this summer in Mitchell, but has it actually been hotter?
Average temperatures last month were significantly higher than historical norms, including a record-setting 106 degrees on June 16 — but so far, temperatures in July have remained around normal.
Data from the National Oceanic and Atmospheric Administration shows that Mitchell is actually experiencing an upswing in summer temperatures since 2014, but it’s not as hot as some summers in the past. Through July 27, Mitchell's average temperature for July was 75.7 degrees, or three-tenths of a degree above normal. In June, Mitchell was nearly 5 degrees warmer than normal at 74.8 degrees for an average temperature, but that was actually cooler than the average temperature for 2020, which was 75.1 degrees.
While not official, a recorded temperature of 103 degrees at the Mitchell Municipal Airport on Wednesday afternoon set a new high for the month, surpassing the 101 degrees recorded on July 4 earlier in the month. Both Tuesday and Wednesday's conditions included a heat index readings in excess of 110 degrees in Mitchell, including 112 degrees on Tuesday. (The 106-degree temperature reading on June 16 is the Mitchell high for 2021 to date.)
Samantha Garrett, a meteorologist for the National Weather Service in Sioux Falls, said the science behind weather patterns tells why this summer feels hot. Large areas of high pressure in the atmosphere — known as ridges — tend to sit over South Dakota in July, drawing warm, dry air up from the southwestern United States. Garrett said these ridges arrived early this year, and hovered over the Great Plains for a longer period of time.
“These strong ridge patterns — we’ve been kind of directly under them for a decent portion for the summer so far,” Garrett said. “When you’re directly under it, precipitation will go to your west or your east, so we’ve been missing out on the rain.”
With amplified ridges hovering above South Dakota, the National Weather Service issues heat advisories and excessive heat warnings based on the severity of conditions. Almost all of South Dakota was under a heat advisory for Tuesday and Wednesday.
While some events in the Mitchell area had to cancel or reschedule their plans due to this week’s heat — such as the Mitchell Farmers Market canceling for the third time this summer due to the heat — programs that fall under the Mitchell Parks, Recreation and Forestry Department do their best to continue operations. Nathan Powell, director of the department, said city-sponsored events always try to find a way to continue operations.
“We try to avoid cancelling programs unless it’s absolutely necessary,” Powell said. “We always ask: ‘Is there an option to move it indoors?’”
Powell said the city has no specific threshold for when events should be outright cancelled, and instead tries to modify programs that can not be moved indoors, with health and safety of participants and employees at the forefront of the decision.
“It doesn’t have to get too hot for someone to have heat stroke,” Powell said. “We can provide more resting time, more water, more resting time and more staffing. Do they have everything they need?”
Jamie Henkel, aquatics and recreation coordinator for the city, added that the pool rarely closes due to heat. Henkel makes sure her employees stay healthy by requiring staff jumps in the pool on breaks, providing extra cooling towels and ice and adding extra staff to create shorter shifts.
However, the heat can stop some guests from coming.
“Sometimes, it’s unbearably hot, and guests don’t want to be in the heat. They’ll go to the bowling alley instead, or the movies,” Henkel said. “It just varies from day to day.”
On Tuesday, Henkel said a group of approximately 50 had cancelled their plans to swim, citing the heat.
Pool visitors Dorothy Dewald and Julie Greene were relaxing in the sun Wednesday afternoon, and said the heat wasn’t enough to keep them away.
“It’s not that bad,” Dewald said. “If you get too hot, you can dip in the pool for a couple minutes,” Dewald said.
Greene said she felt bad for the lifeguards, and hoped they didn’t have to sit in the sun for too long.
The National Weather Service affirmed that South Dakota is due for a cooldown, and added that the state can expect a slightly cooler winter, too.
“Looking ahead in the very short term for Mitchell, today is the last really hot day, so that’s good news,” Garrett said. “As we continue into the end of the week and into the weekend, we’ll see temps near and a bit below normal and rain chances.”
“The farther out a forecast runs, the less reliable it is,” Garrett said, adding that it can be tough to predict what August might bring to the region.
National Weather Service meteorologists in Rapid City and the Omaha, Neb. regions expect a weak La Niña system push out of the Pacific this winter, which typically creates cooler winters with slightly higher precipitation.