Weather Update — September 21, 2026
Transcript
My friends…
Today is Monday, September 21st, and I’m Noé from eastsideweather.com, here for MammothFM in the Eastern Sierra, coming atcha with your local weather report…
There’s no better indication that winter is fast approaching than a dusting of snow at the highest peaks. And that’s what’s in store for us this afternoon. That trough I mentioned last Friday is bringing in just enough cold air for light snowfall at higher elevations. This afternoon will feature increasing thunderstorm coverage and snow above 11 thousand feet. Areas below that could see light rain. Storm coverage will be scattered, but the highest totals could reach half an inch of liquid or up to 5” of snow along isolated peaks, with most areas seeing far less than that. While the majority of the precipitation is concentrated along the Sierra Crest and to the south of Mammoth, areas north will also see scattered thunderstorms, as well as the White Mountains and Inyo Mountains. Precipitation starts up around 2pm and scattered showers will linger until later tonight.
After this, we return to our regularly scheduled beautiful fall weather for the foreseeable future.
In other news, the recent and current weather have moderated the growth of the Dome Fire in Yosemite, and crews are making meaningful containment advances. The Dome Fire is burning 30 miles west of Mammoth Lakes in Yosemite National Park and is 2667 acres and 15% contained. It continues to burn in rugged and remote terrain, and poses no immediate threat to infrastructure. On the Eastside, we’re primarily watching to see where the plume of smoke ends up, but returning high pressure could bring increasing fire activity later this week.
And now the weather for this week:
In Mammoth Lakes and surrounding areas:
- Monday: A 40 percent chance of showers after 11am. Patchy smoke is possible in the morning. Snow level 10,400 feet rising to 11,000 feet. Mostly cloudy with a high of 64 and an overnight low of 46
- Tuesday: Sunny, with a high of 66 and an overnight low of 48
- Wednesday: Sunny, with a high of 71 and an overnight low of 50
Now over to our friends in the Owens Valley:
- Monday: A 30 percent chance of showers, mainly after 3pm. Sunny in the morning, cloudy in the afternoon. A high of 81 and an overnight low of 48
- Tuesday: Sunny, with a high of 84 and an overnight low of 51
- Wednesday: Sunny, with a high of 83 and an overnight low of 53
This has been Noé for MammothFM in the eastern sierra. Join me over on eastsideweather.com where you can get a detailed weather forecast for anywhere in the eastern sierra, and read my longer range weather outlooks
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