Blaine County residents struggling with frigid temperatures last weekend can expect temperatures to warm slightly during the end of this week and into next week, though remain below normal.
Meteorologist John Hinsberger with the National Weather Service in Pocatello said temperatures for this weekend and early this week have been well below average.
“[You’ve had] single digits, single digits below and in some cases, double digits below,” he said. “We’re still well below normal with our temperatures well into next week.”
Data from the Ketchum ranger station show that the temperatures on Sunday and Monday mornings dropped to minus 15, and on Tuesday morning reached minus 18. Stanley tied its record low for the date early Tuesday morning with a temperature of minus 29 degrees.
Hinsberger said the frigid temperatures are due to arctic air coming down from Canada into especially eastern Idaho. He said a large high-pressure ridge off the Pacific Coast is blocking slightly warmer air coming in from the southwest, instead exposing the area to winds from the north.
Hinsberger said the slightly warmer temperatures on Tuesday and through the rest of the week are due to a weakening of that system.
“When you get a weather system strong enough, it can deform that high pressure ridge,” he said.
Hinsberger said the high-pressure ridge was moving slightly south, allowing some warmer air to sneak in. Higher elevations have already been seeing slightly warmer air, he added, with inversions of significant proportions.
“You go up 1,000 feet, you’re going to be 10, 15, even 20 degrees warmer, sometimes,” he said.
Sun Valley Co. spokesman Jack Sibbach said those inversions helped out skiers over the weekend.
“The inversion on the weekend kept the top of the mountain very nice and bearable, with very little wind on Saturday and Sunday,” he said.
However, he said skier numbers were “lower than anticipated” this weekend and especially on Monday.
“Monday was a little tough,” he said. “The inversion was not as strong.”
Cold temperatures weren’t just difficult on skiers. Laura Gvozdas, co-owner of Sun Country Property Management, said she had several apartment buildings with frozen pipes this weekend, and responded to nearly a dozen calls from tenants.
“Even when your heat is turned up, if you have an exterior water line, it can still freeze,” she said. “This was definitely bad. We had some mainlines where whole buildings with multiple units froze.”
Gvozdas said she was expecting more calls this week as frozen pipes thaw out and possibly break.
Keith Anspach, manager of Backwoods Mountain Sports in Ketchum, said equipment rentals have dropped slightly as the temperatures plummeted, but sales of clothing have increased slightly.
“We get more people coming in and getting the big puffy down coats,” he said, adding that sales of warmer boots and hats have also jumped.
Anspach said the shop has also been busy with a rise in ski waxes as people attempt to get ready for warmer weather later in the week. But Scott Savage, avalanche forecaster for the Sawtooth National Forest Avalanche Center, said those looking forward to getting into the backcountry might want to make conservative choices this week.
“Being caught in even a small avalanche in arctic conditions can easily lead to frostbite or hypothermia,” he said.
Savage said cold temperatures also affect avalanche conditions by slowing snowpack stabilization and transforming surface snow into snow crystals called facets that can create avalanche problems after future storms, as the facets do not bond to each other or other snow crystals easily.
Sibbach said Sun Valley Co. expects to see skier numbers rise along with temperatures later this week.
“Skiing is excellent,” he said, adding, “[The cold] keeps the snow really dry and light.”
Kate Wutz: firstname.lastname@example.org