LOGAN — It has been a wet few months in northern Utah, where snow and rain have led to flooding across the region. Behind it is record-setting precipitation with a year's worth amount in just six months.
The Utah State University weather station, for example, collected 22.10 inches of precipitation in the last 181 days — the highest of such a total in the station’s 124-year history. The station averages 19.74 inches each year.
Martin Schroeder, a staff meteorologist at the USU Climate Center, said 17.78 inches have been recorded since Oct. 1 last year, which is the beginning of the recorded 2017 water year. That’s a major leap from the previous record set in 2005 with 14.27 inches.
January was also the snowiest of the months on record, receiving the most snow in a six-month period on record, with more than 5 1/2 feet of snow this season.
Similar patterns are being noticed in Tremonton, Garland and the Cutler Dam, according to KSL meteorologist Kevin Eubank. The drought across the state has disappeared with the abnormal precipitation.
Eubank said the primary cause of the record rain totals have been two jet stream flows: an Arctic stream and another flowing from the Pacific. The Arctic stream brought winter storminess, while the Pacific stream brought in warm, tropical air into the region.
The two jet streams have battled back and forth causing precipitation and temperature swings across the state. At the USU Climate Center, November ended 6.2 degrees warmer than the normal average, while January was 6.1 degrees colder than the average.
The Arctic stream is one Utahns are familiar with during the winter. However, the Pacific stream hasn’t brought an unusual amount of rain to Utah solely— it has brought it across the entire western U.S.
Schroeder said that over the past several years, there has been a high-pressure ridge on the west coast, which is why many in the region had been experiencing droughts.
“This year that has shifted out into the Pacific, so that’s why we’ve been able to see more moisture,” Schroeder said. “More storm systems (are) coming from the north, but also concurrent with that, we’ve also seen several Pacific intrusions — what we call atmospheric rivers. These are what have been responsible for just the ridiculous totals in California that’s been seen.”
The remnants from that storm carried into Utah, where snowpack totals have been rising across the state, but especially in northern Utah. Those Pacific intrusions have crossed over the Sierra Mountains and into the western interior to areas like Nevada and Utah.
“It’s been really wet and it hasn’t been the typical cold Arctic storm track from the northwest,” Schroeder said. “A lot of it is coming from the West and from the Southwest, which is not the norm for this time of year.”
Though there has already been flooding, it still remains a risk. As spring nears, Eubank said soils will warm and allow water to soak in, but the risk of flooding will continue as snowpacks in the mountains melt into streams and rivers.
Schroeder said the foreseeable forecast is relatively dry, but added that projections still point toward a wetter than average spring. That means areas of flooding will remain on edge for the next few months.
“We are still expecting a continuation of increased precipitation,” he said. “Flooding is going to be a general concern come April and May.”