Mammoth Mountain & Eastern Sierra Weather Forecast

Mammoth Mountain & Eastern Sierra Weather Forecast

Footloose Sports Bike Shop - 760-934-2400
Footloose Sports Bike Shop – 760-934-2400

Mammoth Lakes and Eastern Sierra Weather for Friday, September 10th, 2021 @ 9:37 AM

Good morning everyone, checking the window-cast via area webcams, we have pt cloudy skies and a few scattered very light rain showers falling.

Up top, there is a temperature of 43 with a west southwest wind to 44 MPH with gusts to 51 MPH. Down at Main Lodge, the temperature is 51 with a WSW wind @ 4 MPH gusting to 21 MPH. 

In Mammoth Lakes, the temperature this morning is 57 with calm winds. Down in Bishop, the temperature is sitting at 60 with calm winds. The air quality at this time is great in all areas.

Here are some details from Thursday’s light rainfall: The rain gauge at the snow study site showed .03 for the last 24 hours. Mammoth Airport received around .25 of an inch of rain.

Most areas from Mammoth to Bishop picked up at least a trace of rain on Thursday. I did not see any lightning strikes in the area, but I could see flashes off in the distance over the central sierra yesterday evening just after dark.

Rainbow on the Mammoth Airport Webcam
Rainbow on the Mammoth Airport Webcam

Temperatures: Mammoth Lakes will be in the low to mid-70s today with overnight lows in the 40s. Down in Bishop highs are now expected in the lowers 90s during the afternoon hours with overnight lows in the 50s.

Wind Forecast: For elevations above 8800 feet expect it to be windy, with a west wind of 15 to 20 mph increasing to 25 to 30 mph in the afternoon. Winds could gust as high as 45 mph.

For Mammoth Lakes, there will be a west wind of 10 to 15 mph increasing to 15 to 20 mph in the afternoon. Winds could gust to as high as the 35 mph level.

For Bishop and the Round Valley areas there will be a Southeast wind of 5 to 14 mph and winds could gust as high as 21 mph.

Here are the links to the local NWS Forecasts for Main Lodge & the Mammoth Lakes Basin, Mammoth Lakes, June Lake, Crowley Lake, and Bishop.

Fire Weather and Air Quality: We have Extreme Fire Danger in the area at this time. We need several inches of rain or several inches of snow on the ground before all the fire hazard-related closures and restrictions are lifted.

The Air Quality is great today. We will be watching to see if there are any new fires starts due to all the lighting that hit to the west of the Eastern Sierra.

Forecasted Air Quality on Sunday looks Good!
Air Quality on Sunday looks Good!

Today's Weather Story

Weather Synopsis… A trough of low pressure is moving into Northern California and continues to combine with the weak monsoonal flow to bring in a few showers and thunderstorms.

Temperatures have cooled off by 10 degrees as forecasted earlier this week.

By Saturday heights will begin to rise again. The result will be drying with a warming trend for the Eastern Sierra into the middle of next week.

Fantasy Land Long Range Outlook: We are watching for the first dusting of snow. Been seeing off and on chances but nothing to get your hopes up on yet.

The New ECMWF Long range charts got released on the 5th, I have posted the outlooks for the October – January time frame down the page.

ENSO outlook, it’s back to a majority of models showing a weak La Nina once again.

“The strength of La Niña is determined by the extent that the sea surface temperature anomalies fall at or below the -0.5°C threshold. A La Niña is classified as weak when the anomalies range from -0.5°C to -0.9°C, moderate when the anomalies range from -1.0°C to -1.4°C, and strong when the anomalies are -1.5°C or less. The table below lists all thirteen of the La Niña episodes, including their maximum intensities, since the winter of 1949-50”

HRRR Temperature Forecast

HRRR Precipitation Forecast

HRRR Current Dew Point

HRRR Current Humidity Levels

ECMWF EPS Ensemble 500 HA (360 HR)

EPS Temperature Anomaly (360 HR)

ECMWF EPS Accumulated Precipitation (360 HR)

ECMWF EPS Total Snowfall (360 HR)ECMWF EPS Total Snowfall

GFS Total Snowfall (384 HR)


EPS Precipitation Anomaly  Long Range Outlooks from the ECMWF


Mammoth Mountain and Eastern Sierra Weather Posts

Who Are We?

Steve Taylor – Mammoth Snowman Over the last 30+ years, Snowman has spent countless hours studying and learning about Mammoth Mountain Weather and Snow Conditions first hand. He has been skiing around the hill with marked ski poles since March of 1991 so he can measure the fresh snowfall amounts out on the hill. 

Snowman started blogging this information back in 1990 on the old Mammoth BBS system, then the RSN Forums and then on to in 2004 with Video & Photo Blog report. (No YouTube back then). Facebook got added to the fold back in 2008 and then the Facebook Group in 2016. 

Reports, videos, and photos from the website have been featured on both local TV Stations here in Mammoth, along with AP, Fox, ABC, CBS, and NBC News.

Ted Schlaepfer – Mammoth WeatherGuy – The Powder Forecast – Posted Tuesday and Fridays at 5 PM November into Mid May. These forecasts are now responsible for many people getting multiple powder days on Mammoth Mountain over the years.  

Ted’s Bio: Ted has been a full-time Meteorologist (CCM) for the past 25+ years. He has always been fascinated with the weather,” skiing was just a natural extension of my love for snow and rain. I started skiing at age 5,  first discovered Mammoth in 1979 as a youth, and have been a regular visitor since the late ’80s.”.

Here is the link to The WeatherGuys Powder Forecast Page. 

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