By Heather Brown

MINNEAPOLIS (WCCO) — The calendar says it’s the second half of September, but Minnesota temperatures aren’t telling quite the same story.

On Monday, the temperature hit 86 degrees. So, how common are September warm-ups? Good Question.

“Warm spells in September are part of our climate,” says Kenny Blumenthal, Senior Climatologist with the Minnesota State Climate Office. “They are two to three times more likely to happen at the beginning of September than the end.”

Blumenthal says the Twin Cities will hit 85 degrees in 80% of Septembers. Over the past decade, it reached 90 degrees in the Twin Cities in September half the time.

Last year, it was 90 degrees on Sept. 16. In 2017, it was 94 degrees on Sept. 22.

This year’s cooler August and early September might have had an impact on how some people perceive this mid-September heat.

“We’re thinking, ‘Holy mackerel, it’s really hot,’ because your brain has been accustomed to a different environment of temperature,” says Lisa Anderson, an associate professor with the Department of Integrative Biology and Physiology at the University of Minnesota Medical School.

Anderson says the 85-degree temperature in September could feel warmer to some people than the 85-degree temperature in July.

“How profound that is to you is going to depend on your gender, your weight, your age, your genetics — all kinds of things,” Anderson says.

Blumenthal also points out people might not feel comfortable with the high humidity levels of the past week. Those are more likely to occur in August.

“What’s unusual about this particular warm spell is lots of moisture,” he says.

Heather Brown