I usually write the "Chase Powder" forecast on OpenSnow, so why not look at some fall color chases? I have traveled from Alaska to Colorado in the past three weeks and can report some current conditions. Similar to snow forecasting, it is critical to look at elevation-dependent outcomes. Also, areas in the north will often start peaking earlier due to cooler temps and less sunlight due to the earth's tilt, which causes shorter days. You can chase colors for several weeks. 

Below: Mom protecting her cubs in the Katmai of Alaska (Early September) Photo: @powderchasersteve

The Science:

Less daylight is the primary influencer on the changes in leaf pigmentation as the process of chlorophyll production is reduced. The veins that carry fluids into and out of the leaf gradually close off as a layer of cells forms at the base of each leaf. These clogged veins trap sugars in the leaf and promote anthocyanin production.

The leaf is ready to fall once this separation layer is complete and the connecting tissues are sealed off. Falls that deliver abundant sunshine and cooler temps (Not freezing) will do best for colors. Frigid temps and snowfall can very quickly deteriorate things. Last weekend, snowfall teased central and southern Colorado, making for some great photos. That cold front was short-lived and should not have a major impact on colors. 

Below: Check out the new OpenSnow Fall colors map. (New for 2024). Find it in "Maps".

Below: Snow impacted the central and southern mountains of Colorado on September 21 bringing an epic shot. Very warm temps have since then melted the snow.

Photo: Taylor Ahearn-Crested Butte Mountain Resort.

The Chase?

Peak colors are currently breaking out at the upper and lower elevations of the Tetons, Yellowstone National Park, and most of Montana's western mountain ranges. In Utah, I went to Park City last week to experience brilliant reds (maple trees and shrub oak) at lower and upper elevations. Utah benefits from the opportunity to chase twice, first with the reds and then the yellow 7-10 days later (almost like double powder days).

There are reports in the Park City area that yellows are starting to pop above 8,000 feet (still green at the bases). Aim for higher-elevation drives such as Guardsman Pass, Mirror Lake Highway, Uinta Ranges, Cottonwoods, and mid-to upper Logan Canyon (Known for brilliant reds). The yellows will fill in quickly at lower elevations this weekend (September 28-29).

Below: Park City, Utah at 8,000 feet- September 25- Photo: Jay Goldberg 

Below: Powderchaser Steve sampling the early reds in Park City (September 19th) before the yellows appeared (Utah scores two distinct color chases with the reds first). The yellows are just starting to pop in the lower areas of Park City. Upper elevations are doing well, including areas of southern Utah (Brian Head). 

In Colorado, fall colors are peaking along the I-70 corridor, especially from Silverthorn to Avon. I sampled the colors on Thursday, September 25, on an epic mountain bike ride early this morning in Avon. The colors are epic, especially on the west side of the Divide. I-70 is prime right now! 

Below: Thursday, September 25, Vail Valley with bright yellows peaking at all elevations. The I-70 mountain corridor will be very busy this weekend. Photo: @powderchasersteve 

Further south, the colors are peaking only at upper elevations such as the Maroon Bells or upper aspects of Ajax Mountain (Aspen). The town of Aspen (7800 feet) is starting to change (Yellows 20%). Chase to Twin Lakes near Independence Pass or head to the Bells that are at peak. 

In southern Colorado, reports are primarily green in Durango (Lower elevations) with vivid colors on the mountain passes. As mentioned above, southern areas, including New Mexico, tend to change a tad later, but much of the higher terrain is well underway and near the peak. 

Bottom Line: Watch the OpenSnow foilage maps for daily updates. Do your homework on elevation (You can't go wrong in the Rockies, currently above 8500 feet with many areas peaking). I often chase from Colorado (Higher terrain) down to New Mexico or north to Utah, where lower elevations begin to pop later, such as Park City. Sun Valley is also a great latter option (Currently just starting in the lower valley). Chases can last several weeks. As a mountain biker, I prefer the latter chases when the trails turn into yellow brick roads (Pick a windy day and ride with the leaves falling). There is nothing better than fast-flowing trails wholly covered in yellow. 

UPDATE: September 25: Independence Pass and Maroon Bells are all peaking (90%). 

Below: Maroon Bells September 25.   Photo:@powderchasersteve 

Below: Models show a continued dry pattern into the first week of October with unseasonably warmer temperatures. The map shows precipitation through October 5th (Image—Weather Bell—GFS). This increases the chances for an extended period of color, as moisture will be very limited. 

Below: High pressure will stay in control for most of the west well into October. There is a fast-moving system noted for mid-next week (October 3) that will likely impact the northernmost areas of the Rockies, primarily the east side of the Divide including the Front Range of Colorado (Some moisture is possible). Areas west of the Divide might stay dry into the first several weeks of October. 

Hopefully, we will be talking about white stuff in the next post. Expect many deep days this season if you are willing to chase powder. La Nina is likely to favor the northern Rockies and the PNW. At the same time, central regions (I-70 corridor including areas of Utah) are not impacted by either La Nina or El Nino (Sits in the middle). These central areas have an equal chance of a normal snowfall season. Areas of the southern Rockies might see less snow, including the Sierras (Wildcard). 

The good news is that temperatures during La Nina tend to be colder. There have also been exceptions where La Niña climate norms have trended high snowfall south. We can only forecast from historical data.

The bottom line is that if you chase powder and follow the OpenSnow "Chase Powder" forecast, you stay in the deep all season. 

See you on the slopes soon and enjoy the fall colors!

Powderchaser Steve
Chase Powder Forecaster