PETER SINKS, Utah (ABC4) – As Utah’s scorching heatwave covers the state and residents battle triple-digit temperatures, there’s one special place in Utah completely immune to summer weather, boasting wintertime temps all year round.
Located about 20 miles northeast of Logan and about 2,000 feet above Logan Canyon, is Peter Sinks, a place that’s seen some of the coldest-ever recorded temperatures among the lower 48 states, according to Utah State University’s Utah Climate Center.
At around 10 a.m. on Monday, July 11, the average temperature at Peter Sinks was a crisp 68.6 degrees Fahrenheit.
The lowest temperature ever recorded in Peter Sinks was on Feb. 1, 1985, dropping to a freezing -69.3°F, marking the second coldest temperature only bested by a recorded -69.7°F at Roger’s Pass, Montana in Jan. 1954.
Peter Sinks was discovered by a Utah State University graduate student, Zane Stephens, in the mid-80s, according to UGS.
“He intuitively understood that that kind of sink or depression way up top of the high elevations, would be a perfect place for cold air to pool,” says John Meyer, a climate scientist at UGS. “And so based on that intuition, they put up weather stations in the middle. And we’ve only been recording temperatures since I think 1983, 1984…”
What causes such frosty weather to permeate this area?
Experts at the Utah Climate Center say it’s a combination of the area’s “unique basin topography, high elevation, and dry climate.”
Sitting at an elevation of 8,164 feet, Peter Sinks is a natural limestone sinkhole extending about a half-mile in diameter. Experts describe it as a large insular bowl that has no outlet to drain air or water. It’s comprised of two connected depressions created by multiple sinkholes that are surrounded by ridges standing hundreds of feet above the basin’s low point, according to UGS.
Peter Sinks is a closed basin, which means air can become trapped inside. The area’s high elevation means that the air is often cold and dry, which is the heaviest type of air.
In other words, an inversion, much like those experienced along the Wasatch Front and Cache Valley in the winter, occurs in this basin.
According to UGS, cold air collects inside the cold basin and slides downslope into the basin floor in a process known as cold air pooling. This phenomenon can result in a variety of temperatures, oftentimes hitting extreme lows, especially during wintertime.
Experts say a 30-degree change in just nine minutes can be possible. Peter Sinks remains frequently cold throughout the year with vegetation inside the bowl consisting mainly of shrubs since it’s too cold for any trees to grow.
The rocks discovered inside the basin – limestone and dolomite – are easily weathered, creating large cavities and sink holes. In the case of Peter Sinks, the holes can run hundreds of feet deep.
With the current heatwave and rising temperatures in Utah, experts say it wouldn’t be surprising if Peter Sinks also sees warmer weather in the years to come.