In Jackson, the month of June is off to a blistering start.
The valley is set to experience several unseasonably hot days in the coming week, with highs expected to reach the upper 80s and low 90s.
Locals will have noticed temperatures fluctuating in the past weeks between unusually cold and exceedingly warm extremes. According to meteorologist Jim Woodmencey, the extremes and variation in temperature are the result of a trough-ridge weather pattern.
“You get a southerly flow that brings warm air all the way up to the desert Southwest, and then you have a trough that goes through and brings cold air from the Pacific Northwest and the Gulf of Alaska ... back and forth,” Woodmencey said.
The average high temperature in Jackson for June is 72 degrees, so the coming week’s expected highs are certainly above average, but they are not unprecedented. The highest recorded temperature of this month occurred June 26, 1988, the year of the Yellowstone National Park fires, when thermometers reached 95 degrees.
The summer of ’88 was also one of the driest summers on record.
“We had virtually no precipitation in June, July and August that summer,” Woodmencey said.
That summer multiple fires burned through nearly 800,000 acres in Yellowstone, or roughly 36% of the park, and threatened the Old Faithful Inn and other important landmarks.
It is too early to tell what impact this early heat wave will have come fire season, but this month’s spike in temperatures will likely have the biggest effect on runoff levels.
“The more significant thing this early in June is that, even up in the mountains at 10,000 feet, it hasn’t gone below freezing for the last week, so you know, we’re hitting our maximum runoff,” Woodmencey said.
Despite the above-average highs the first week of June, people will have to wait and see whether this month will break any records, he said.