Weather Update — September 25, 2026

Transcript

My friends…

Today is another stunner of a day on the Eastside, and I’m Noé from eastsideweather.com, here for MammothFM in the Eastern Sierra, coming atcha with your local weather report…

We’ve had nice fall weather with some patchy smoke impacts from the Dome Fire, which is now over 4000 acres and still at 15% containment. Troughing activity will help limit the growth of the Dome Fire, but it will continue to burn for the foreseeable future.

My friends, if you’ll recall, on Wednesday’s update I was a bit doubtful of the warm fall weather being shown in models. It just hasn’t held up as troughs have constantly found a way to slip into the short range. By the way, trough is a word you’ll hear me using a lot in my discussions. A trough is basically an area of lower pressure, associated with a dip in the jet stream. Some are weak and dry, bringing just cooler, gustier weather, while stronger troughs can produce major storms and atmospheric rivers.

And now, that pattern looks set to continue. Another weak trough is likely Sunday, with yet another possible toward the end of next week. That means cooler temperatures and increasing chances for precipitation, especially as we head into next week.

The Sunday-night into Monday trough is particularly interesting because it could tap into some remnant moisture from Hurricane Polo, potentially bringing showers and a light dusting of snow to the higher elevations. That outcome is still uncertain, though, with only some models showing meaningful precipitation.

And this weekend, we’re watching closely to see where the plume of smoke ends up from the Dome Fire as Trailfest gets underway, as well as watching the string of troughs throughout next week as the Mammoth 200 miler follows. In terms of smoke impacts this weekend, it looks mostly like we will be under Southerly or Southwesterly flow, so the worst of the smoke should hopefully be lifted to our north this weekend… Fingers crossed!

And now the forecast for this weekend:

In Mammoth Lakes and surrounding areas: Friday and Saturday will be mostly sunny with highs in the upper 60s, but with gusty southwest winds both days. Sunday turns cooler, with a high near 62 and an overnight low in the upper 30s. By Monday, highs fall into the upper 50s, with a slight chance of rain and high-elevation snow showers.

Down in the Owens Valley: expect sunny and breezy weather Friday and Saturday, with highs in the mid to upper 80s. Temperatures cool into the low 80s Sunday and upper 70s Monday, with overnight lows generally in the mid to upper 40s.

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. I promise you, the weather forecasts you’ll get on eastsideweather are so much more accurate than the Apple weather app!