Weather
A compact closed low Monday night into Tuesday (Sep 22–23) splashes the first legit white on Colorado’s high peaks and passes. Best shot is the northern Front Range and the Divide east of Vail: Berthoud and Loveland Passes land 3–8 inches, while the tallest Front Range summits can flirt with 8–12+ inches. Summit County upper elevations score 3–6 inches with little in towns. Farther west, Vail Pass trends mixed with a coating to a couple inches on colder shoulders. The Park Range and Gore crest pick up a few inches; central ranges see a dusting to 1–3 inches on the highest ridges; southern ranges mostly a skiff, with the very top of the Sangres and Pikes Peak pulling 2–4 inches. Snow levels hover 9,000–10,500 feet north and ~11,000+ feet south. This is not blower. Expect dense, low-ratio snow with wind texture up high.
A sharp cold front and strengthening mid-level low sweep Colorado Monday night, then slide east Tuesday evening. Moisture and upslope combine with 700-mb temps near 0 °C to drop the snow line to ~9,000–9,500 feet before daybreak Tuesday, briefly ~8,500–9,000 feet in heavier bursts. Precipitation is most widespread Tuesday morning through midafternoon, then fades quickly by evening. A warmer, drier ridge rebuilds Wednesday through Friday.
Storm totals by zone (through Tuesday evening, upper-mountain unless noted)
- Front Range alpine and passes (RMNP high country, Indian Peaks, Berthoud, Loveland): 3–8″ on passes, 8–12″+ on the highest peaks. Towns like Winter Park and Silverthorne see little or none.
- Summit County (A-Basin upper, Breck high alpine, Copper/Keystone summits): 3–6″ above ~11k, minimal below.
- I-70 west of the Divide and central ranges (Vail/Beaver Creek, Elks/Aspen Snowmass, Sawatch/Monarch): 1–3″ on the very top ridges, locally a touch more in favored nooks; Vail Pass leans rain/snow mix with little on the road surface.
- Northern mountains (Park Range/Steamboat, Gore crest): 2–5″ on the highest ridgelines; Rabbit Ears Pass likely mixed with light, brief impacts.
- Southern mountains (San Juans) and adjacent high terrain: Dusting to 1″ on the very tops. Sangres and Pikes Peak manage 2–4″ near the summits.
North of I-70, snow levels settle ~9–10k feet at the morning peak, then lift as rates ease. Central zones sit ~10–11k feet, and the southern ranges mostly above 11k. Thermal profiles and pass-level rain/snow mix point to low SLRs near 6:1–10:1. Expect heavy, pasty snow with wind effect on exposed ridges, plus slushy intervals on colder road shoulders during bursts. Behind the front, northerly to north-west flow turns breezy. Ridge gusts commonly 25–35 mph with higher pockets in showers. Visibility will drop fast in the heavier cells above treeline.
Showers taper quickly by Tuesday evening with lingering flurries along the west side of the Divide into early Wednesday. A dry, warmer stretch follows midweek. Any next weak signal waits until late weekend or early next week.
