They found that a significant cold spell in the Northern Rockies regularly occurs around Aug. 24-26. A shorter August Singularity also tends to occur around Aug. 13. Temperatures can drop by as much as 40 degrees below average during the event.
A singularity is a weather condition that tends to occur near a specific date more frequently than chance would indicate, according to the American Meteorological Society's Glossary of Meteorology.
The New England region's "January Thaw" that regularly occurs around Jan. 20-24 is the most extensively studied by far.
In the West, Sandman said, the most well-known and predictable weather event has long been the start of monsoon season that arrives in Arizona and New Mexico in June. But the August Singularity is not far behind.
Julia Winter wrote:Hey, what happened to the August Singularity?
Oh wait - I see, it's not due until the 24th. Hope y'all are keeping cool!
David Lehnherr wrote:Grew up in Montana, and now live in south-central Montana. Our weather is becoming even less predictable than it used to be. Our summers are definitely trending towards warmer and longer. One of the odd things is how we're seeing thunderstorms more frequently in summer afternoons now. Definitely makes planning outdoor activities more interesting.
Jocelyn Campbell wrote:A Montana valley (was it the Swan?) had a frost last week with our August singularity weather - we did not. One of the many reasons Paul prefers higher elevation hillsides to valley floors for growing things.
Jocelyn Campbell wrote:
The last two days of September (2016) were sunny during the day, and rain after dark. This really does happen quite frequently.