A dusting of snow is settling onto the peaks above Mammoth Lakes just as the aspens and cottonwoods below turn gold, giving the Eastern Sierra its signature late-September mashup: snowliage. Sierra Nevada summits are getting a coating of white while deciduous trees keep turning color down in the valleys, a seasonal overlap that tends to show up as September winds down and fall gives way to winter in the region.
Fall Colors Were Already Popping by Mid-September
The color show didn’t wait for the equinox. As of Sept. 17, fall was already coming in quickly around Mammoth Lakes, according to Eastern Sierra Now, which described pockets of color starting to take over the landscape. The outlet pointed hikers toward orange willows and shifting yellow aspens along Mammoth Creek, up in the Mammoth Lakes Basin, and around Convict Lake.
By Sept. 22, the calendar had officially caught up with the scenery: the 2026 autumnal equinox landed that day, marking the point where fall and winter start trading places in the Eastern Sierra. Snow was gathering further up the mountains while the deciduous plants below kept their golden display going, and the Visit Mammoth team described the overlap as a little snowliage magic, according to photos and videos shared on social media, per NBC 7 San Diego.
Color Varies Widely Depending on Elevation
Not every spot along US 395 is glowing yet, and the color really does depend on how high up you go. Mono County’s fall colors report found Sagehen Summit progressing quickly to 75-100% coverage, earning a “Go Now” label, while Virginia Lakes at 9,819 feet sat at 50-75% and was also marked as near peak, according to Mono County.
The June Lake Loop along Highway 158 told a different story. That area, sitting at a lower 7,654 feet, was reported at just 0-10% color, with most of the loop still green, the same county report noted. Mono County typically sees its colors begin at higher elevations in mid-September before spreading through October all along US 395, and the agency’s report projected that the next three to five weeks should bring plenty of fall color across the county, weather permitting.
Snow Dusting, Not a Storm
The snow side of snowliage has stayed modest so far, and forecasters have been careful to frame it that way. A Sept. 25 discussion from Mammoth Snowman flagged a low-pressure system that could bring very light rain with snow above the 9,200 to 10,200 foot level, with cooler weather expected to linger into the middle of the following week before a return to ridging. That same source noted that light snow can fall in late September, but consistent snowfall usually doesn’t arrive until late October or early November.
A Sept. 28 forecast update kept the trend going. Moisture pushing inland from Hurricane Odalys brought roughly a 40% chance of rainfall to the area, according to Sierra Wave, with snow levels in Mammoth expected to drop to about 9,000 feet and little or no accumulation expected. It’s the kind of dusting that photographs well against golden leaves but falls well short of the actual winter storms expected in the weeks ahead.
Opening Day Still Six Weeks Out
For skiers and riders counting down the days, the target date hasn’t moved: Mammoth Mountain’s 2026/27 opening day is scheduled for Nov. 13, running from 8:30 a.m. to 4 p.m., according to Mammoth Mountain. Festivities are set to include the annual first chair and banner breakthrough, followed by a toast to the new season with resort mascot Woolly at the bottom of Broadway Express.
That puts opening day roughly six weeks after this late-September snowliage stretch, and resort history suggests the exact date can shift with the weather. Opening day typically lands between Nov. 10 and Thanksgiving depending on storm activity and snowmaking, per Mammoth Snowman, and Mammoth Mountain’s season traditionally runs from November through June. The mountain, whose summit tops out at 11,053 feet, is still riding the memory of its snowiest season on record in 2022-23, when Main Lodge measured over 700 inches and the summit came close to 900, per the resort’s own snowfall history. For now, Mammoth Mountain is offering preseason savings of up to 35% on lodging and up to 50% on lift tickets ahead of opening weekend.
