2:40 PM, Friday, October 5, 2018
By the time you read this the Friday warm-up may be history. At 2:30 PM a strong cold front was through Fort Collins and moving quickly southward. It was mid 70s in Denver and upper 30s in Cheyenne.
An autumn-like air mass will settle in and a large storm system developing over the western states will influence the region over the next 4-5 days. Although Saturday will be cooler, the real effects of the western storm may not reach the Front Range region until late in the weekend. Expect some areas of drizzle early Saturday and some showery rains around later in the day, but it could end up being mainly dry. The exception is in western Colorado where the chance for prolonged precipitation begins to ramp up late Saturday.
On Sunday the Front Range and eastern plains will likely see and increased chance of more widespread precipitation late in the day lasting into at least Monday.
Snow level: although it will be cool behind the cold front, the middle levels of the atmosphere won’t be terrible cold at first, so snow levels are likely to stay above treeline this weekend, possibly dipping below treeline in western Colorado by late Sunday. Sunday night through Monday will likely see a gradual lowering of the snow levels. The forecast challenge is whether there will still be enough moisture around for snow in the urban corridor early next week, and that’s a question I can’t answer with confidence yet. I will update later in the weekend.
So the bottom line, cooler this weekend with increasing chance of precipitation by late in the weekend. There is very little chance for snow in the lower foothills and plains this weekend, but it can’t yet be ruled out for early next week.