Weather folklore… there’s a lot out there and Montana is no stranger to some crazy weather swings, patterns, etc. But one particular long-standing phenomenon (mainly among the fire community) is legit: the August Singularity. And it has implications for the wildfire season.
The American Meteorological Society’s glossary defines a singularity as “A characteristic meteorological condition that tends to occur on or near a specific date more frequently than chance would indicate.”
The most commonly known singularity in the western U.S. is the southwest monsoon season - we’ve heard of that one, right?!
For the northern Rocky Mountains, a 2008 study, by North Carolina professors Peter Soulé and Paul Knapp, found a significant deviation in temperatures around the third week in August - sometimes as much as 40 degrees below seasonable norms. The data indicate that a single-day negative maximum temperature singularity exists for August 13th, specifically.
Further, a 3-day singularity event exists for August 24–26th (August 1992 in central MT ring a bell?).
The study concluded that “the concept of an August Singularity in the northern Rockies is valid, because the high frequency of recorded negative maximum temperature anomalies suggests that there are specific time intervals during late summer that are more likely to experience a major midlatitude storm”.
The main benefit we see for the August Singularity is the reduction in temperatures which help wildfire control efforts common this time of year in the region.
Of course we know fire season can extend well into the fall. The August Singularity can be a huge help to firefighters, but it’s not a fire season-ending event… think of it as an obvious slowing of the season… and this year’s was right on time!
If memory serves, the Western MT Fair was held in mid August until maybe the late 90’s early 2000’s because it always rained. I could be wrong, but I was a 4H leader way back when and I remember the dates being changed. It was quite a big deal at the time.
I’ve noticed and anticipated this moment every August for years. I just didn’t realize there is a term for it. Loved this article. I was already on the fence to subscribe but this one got me. Keep up the great content, Erin!