Cold temps unrelated to polar vortexJan 7, 2014 By Katie Roenigk, Staff Writer
The low temperatures and snowfall that hit Fremont County over the weekend were not related to the distorted polar vortex affecting much of the United States this week.
"The cold weather we got just happened to be the typical cold push out of the north," National Weather Service meteorologist Brett McDonald said Tuesday. "We get fresh snow on the ground, then clear skies --and it's Wyoming, the temperatures drop."
He said it likely would have been more frigid over the weekend if Fremont County had been part of the vortex --a system of strong, cold wind currently centered over the country's Midwest region.
"If that cold air from the polar vortex made it (to us), I'd expect to see a lot more -20s," McDonald said.
Instead, the temperature in Riverton was at 5 degrees Tuesday morning and had risen to 15 degrees by 11 a.m.
"We didn't get nearly as cold as the prior morning," McDonald said. "That was actually the clouds that helped keep it warmer last night."
On Monday, a site at the Wind River south of Riverton read -29 degrees at 2 a.m. In Lander and Jeffrey City it was -23 degrees at 7 a.m. Monday, and the temperature was -14 degrees at 6:15 a.m. Monday near Boysen Reservoir.
Elsewhere in Fremont County, however, warm winds from the surrounding mountains helped temperatures stay higher, while inverted cold air remained in the basin.
"Yesterday Dubois got up to 30 degrees, and Crowheart got up to the mid 30s, whereas up here at the office in Riverton we only got up to 4," McDonald said.
The trend continued on Tuesday, with temperatures at 35 degrees in Crowheart by midmorning.