Friday, September 16th, 2022 @ 10:01 AM – Good morning there is a change in the weather coming with the first Fall weather system of the season dropping into California late Sunday into early next week.

As it stands now Mammoth Mountain is just a bit too far south to see the main effects of this system. You can expect to see some snow showers late Sunday into Tuesday from 9000 feet and above.

It does look like at some point there will be a dusting on the ground that you will be able to see on the Mountains webcams.

If the low sags south a bit there could be a couple of inches of snow over the upper part of the hill. There is a fair amount of moisture being pulled in with this low that is forecast to hit the Mesquite Fire with one-half to 1 inch of rainfall.

Now that there is some real weather to talk about I will have a quick update on this incoming system again on Saturday and on Sunday. 


Mammoth Mountain Weather Forecast

For today expect hazy skies with light winds, resort level highs at 8900 feet (Main Lodge and the Mammoth Lakes Basin) will be in the upper 50s by mid-day. Expect lows in the low 40s tonight then dropping into the mid-30s through midweek.

As the low approaches late this weekend temperatures are expected to come down 5 degrees on Saturday and 5 more degrees by Sunday. Better layer up if you’re out for an adventure this weekend.

Winds will be out of the NE this morning and shift south by the evening hours if not earlier.  Expect wind speeds of 10-15 MPH with gusts in the 20-30 MPH range.

On Saturday there will be a southwest wind of 10 to 15 mph increasing to 20 to 25 MPH in the afternoon. Winds could gust as high as 35 – 45 MPH from the Resort level to the top of the Mountain.

On Sunday expect wind speeds to be in the 45-55 MPH range, brrr winds chills will be into the teens. There will also be some clouds increasing on Sunday with a 20% chance of snow or rain showers later in the day.

Mammoth Lakes Weather Forecast

For today highs will be in the mid to upper 60s with lower 60s on Saturday and then Sunday into mid-week expect the mid to upper 50s with nighttime lows in the 30s. 

There is a chance of light rain showers Sunday night into Tuesday as the snow level looks to remain high. If the low sags south a bit that could change so stay tuned in to the forecast.

If you’re venturing to Bishop expect clear skies with highs in the upper 70s to low 80s today and 70s this weekend with lows into the 40s by sunrise.

Mammoth Weather Weekend 2 Outlook – Looks dry, clear, and cool… Fall like. Read the 10-day discussion below to learn more.

Here are the links to the specific highs, lows, and wind speeds for many of the major recreation points in the Eastern Sierra: Mammoth Mountain Main Lodge, Top of Mammoth Mountain, Mammoth Lakes, June Lake, Crowley Lake, Toms Place, Rock Creek Lake, Bishop & Mill Pond, South Lake. 

Please Note: Fire Restrictions are in place on all National Forest Service and BLM Lands in the Eastern Sierra.

Current Satellite View

Mammoth Mountain Weather View

Haze & Smoke Forecast

As forecasted the haze from dissipated smoke is in the area today from Mammoth Mountain down to Bishop. The good news is the HRRR model has all the junky air out of the area by Saturday morning for Mammoth and mid-day for Bishop.

HRRR Smoke Forecast for Mammoth Mountain, Mammoth Lakes and Bishop, California
HRRR Smoke Forecast for Mammoth Mountain, Mammoth Lakes and Bishop, California
Mammoth Mountain 10 Day Weather Outlook & Long Range Discussion

Friday, September 16th, 2022, @  11:39 AM – The Weather Story for Today:

By late this weekend, the first fall trough of the early season starts to increase winds and will lower temperatures to well below normal.

As the low drops down and into California late Sunday into Monday, its track is a bit to far north for Mammoth Mountain to get the main benefits of this first system.

Looking at the EPS solution this morning that low still looks to bring in some showers to the high country with the first dusting of snow possible over the higher elevations.

Seems like there are a lot of years where that first small dusting of snow the locals can see is around 9/21 the first day of Fall most years.

The showers look to be all done on Tuesday and then the area will start to warm up under the next ridge of high pressure. Yes, it will warm up again but nothing like the last heat wave of 10 days ago.

Snowman- Pray for Snow!

Here is the EPS Ensemble Model showing the Fall equinox low coming into California.

14-km EPS Global North America 500 hPa Height Anom
14-km EPS Global North America 500 hPa Height Anom

The EPS has some moisture in the area over the next 10 days, let’s hope for that first dusting of snow and more rain for all elevations.

14-km EPS USA California 24-h Precipitation

Love to see the blue over California which means cool Fall Weather in the Eastern Sierra. Near the end of this run, you can see how the area warms up once again. Nothing major, just some nice warm Fall days.

14-km EPS Global United States 2-m Temperature Anom

Here is the EPS 45-Day Height and Anomaly E. Mean – Looking like a warm and tranquil October if this Long Range Outlook comes to reality.  This has been expected, better to have weather in November than in October.

14-km EPS 46-DAYS North America 5-day Avg 500Z Anom

Here is the EPS 45-Day Outlook on Precipitation. Looking the weakest it has for a while now, after the next low comes in that’s it for a while.

About what we expected for October. Let’s hope the EU seasonal shown down the page is right about November, we could use some snow and cold air.

14-km EPS 46-DAYS United States Accumulated Precipitation
November into March Mammoth Weather Trends

9-7-22 @ 9:12 AM – A weak La Nina will be gaining some strength into late Fall and then is forecast to start to weaken and then go neutral sometime by late December into early February.

How this all plays out for winter is still up in the air.  The good news from what we are seeing right now is the longest-range models are not day in and day out dry like we were seeing at this time last year.

An updated run of the EPS Seasonal is now out and posted below. The Mammoth Mountain area on these updates would be in for an average year if what we see below came to fruition.

Again long range data is not a forecast just an outlook, I personally like to look at all the data and see what the trends are. 


ENSO - La Nina & El Nino

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. 

Click Here to Learn More About the People Who Make a Reality

Mammoth Mountain Weather Forecast and Long Range Outlook