High humidity and heat bursts are unusual for summer weather in Oklahoma
The National Weather Service has issued 17 heat advisories so far this summer. Meteorologist Ben Thorn said high dew points are to blame for temperatures that aren’t in the triple digits but feel hotter than summers in the past decade.
“Last year, in July about this time, temperatures might’ve gotten to 112, 110 degrees several days in a row,” he said. “Even when temperatures broke records during the drought in 2011 and 2012, it still didn’t feel this hot because it was a dry heat.”
Thorn said high temperatures with lower humidity help the body cool down when sweat evaporates off the body through a process called evaporative cooling. When there is too much moisture in the air, the atmosphere has no room for our sweat.
“Even though it was really hot last year and you needed to take precautions, these days we’re seeing 80% to 90% humidity. A comfortable dewpoint hovers around 60%,” he said.
According to the Oklahoma Mesonet, a network of environmental monitoring stations, 60% is the annual average relative humidity in the panhandle, while it hovers around 70% in eastern and southeastern parts of the state.
Along with the unusually high humidity, Cherokee, Oklahoma, and parts of western Kansas experienced a rare weather event called a heat burst on Monday, which could cause damaging wind gusts. Thorn said the decaying thunderstorms responsible for the heat bursts aren’t common during this time of year.
“They’re rather common in May and June, but not in July,” he said. “They move up into Nebraska and the Dakotas during this time of year. The one in Northwest Oklahoma was about 61 miles per hour.”
The National Weather Service has made recommendations to stay hydrated and in the shade during the hottest parts of the day this week. A heat advisory continues through 8 p.m. Wednesday.