Cold snap will end, but quickly return by early next week
Smart gardeners have already pulled their summering house plants off the stoop and returned them to the living room. The recent cold snap means the last killer freeze of 2013 is fast approaching.
Between Oct. 1 and Oct. 20, daily high temperatures across the Grand Valley averaged nearly 9 degrees below normal, 4 degrees below normal overnight, the National Weather Service reported.
Sept. 26 was the last time the daytime high climbed above average. It was a balmy 78 degrees, three degrees above the norm of 75, the weather service said.
Oct. 16 saw a record low of 29 degrees, the first freeze of the season, said Chris Cuoco, a senior forecaster for the weather service.
A large trough carried low cloud cover, rainstorms and lower temperatures to the Grand Valley from the Pacific Northwest during the first part of the month, Cuoco said.
This week, however, building high pressure is expected to cause temperatures to rebound to above normal.
The reprieve from cold weather will be short-lived. Long-range forecasts call for freezing air to drop down from the Arctic Circle, possibly by early next week.
“Right now, the long-range models are showing a pretty strong and cold system diving down from the Bering Strait through Canada and down into our area,” Cuoco said. “That’s going to carry some very cold temperatures, especially along the Front Range and significantly colder here as well.”
Despite the cold, there’s still a couple more weeks left in the Grand Valley growing season, according to Susan Rose, horticulturist for the Tri-River Area Colorado State University Extension.
“We’ve had a couple of freezes, but for the most part it’s not been too bad,” Rose said. “As long as the temperature is hovering right around the edge of freezing, people can easily cover (their outdoor plants).”
Damage to plants normally results from extended periods below freezing, she said.
“On average here in the valley, our last killing frost (28 degrees or colder) is the last week of October,” Rose said.