Mammoth Mountain Weather Forecast & Discussion

Monday, April 3rd, 2023 @ 10 AM – Good morning, an inside slider-type low-pressure system is moving down the east side of the Sierra Crest today. These types of systems have limited moisture with lots of cold air along with very windy conditions.

Snowfall amounts so far have been in the 2-3 inch range and there could be an inch or two of additional snowfall today. This will be the last of the snowfall for about a week to 10 days.

Once this low-pressure system moves to the south and east of the area there will be a ridge of high pressure that will set up to the north and east of Mammoth Mountain.

The position of the ridge has changed since the update I did on Saturday with the high a bit more to the east than it was forecasted before. The result of that change will mean that instead of a North to NE flow it looks like Mammoth will come under a South to SW flow.

That type of pattern will allow a spring thaw in sun-exposed locations all the way up to MC Coy Station by next weekend.

Temperatures in the area today have dropped 20-30 degrees and will slowly start to rebound this Tuesday and Wednesday. Temperatures at the 9000-foot level by Friday will be into the upper 30s to low 40s and by Sunday temperatures will have climbed into the upper 40s to low 50s at Main Lodge.

In the Extended Outlook period, this taste of spring will come to a quick end at day 10 as the ensemble models have troughing starting to set up again for California and the Eastern Sierra. That would mean colder wintery weather and a chance for some additional light to moderate snowfall.

I will update the extended data down the page today, so check back in a couple of hours if you happen to be reading this line…

If you’re going to be out on Mammoth Mountain on Tuesday expect pt cloudy skies with breezy conditions. Temperatures will be in the low to mid-20s by mid-morning with West winds in the 15-30 MPH range with gusts @ 35-40 MPH over the higher elevations and in wind-prone locations.

By Wednesday skies will be mostly sunny with highs in the upper 20s to lower 30s. Winds will be out of the west in the 15-30 MPH range with gusts @ 35-40 MPH over the higher elevations and in wind-prone locations. 

For Thursday and Friday, the slow warming trend will continue along with decreasing winds. It will really start to feel like spring at this point with the warmer air temperatures and the snow over the lower 1/3 of the hill converting over to spring conditions in the sun-exposed spots.

For the weekend, the weather out on Mammoth Mountain looks to be great with highs in the Main Lodge area expected in the upper 40s to low 50s under sunny skies with light winds in the forecast.

Mammoth Lakes will also thaw out with temperatures into the mid to upper 50s. The Bishop area by next week should see the upper 60s to lower 70s.

Ski Ya Later, Snowman

NWS Mammoth Weather Forecast Photo
NWS Mammoth Weather Forecast Photo
West Coast and Eastern Pacific Satellite View
West Coast and Eastern Pacific Satellite View

4-3-23 @ 1 PM – Now that April is here you can expect the endless storm train to wind down giving Mammoth locals a chance to finally dig out and recuperate from the biggest winter in the last 100+ years. 

Once this weak system in the area today moves to the S and East high pressure will move in a dominate the weather for the next week to 10 days.

Around day 10 you can see on the EPS model below that more troughing looks to affect the west coast out to day 16. The weak troughing setup would be good as the result would be a slow snow melt.

Overall I think that the spring and especially the summer will end up being cooler than normal… why you ask? A moderate to strong Eastern-based El Nino will be growing and in play possibly by July and that tends to bring cooler summers. If that does not verify I am sure the area will heat up by July 4th.

By the Fall, the developing El Nino, according to the CFSv2, will be in the 1.5+ range, and with it being eastern-based California could be headed for back-to-back well above-normal winters.

Some of the models have the event in Super El Nino Strength. And before you call foul on El Nino, the last super El Nino was centrally based and for those who read my weather stuff, I stated that the 2016 season would be a total bust the summer before.

This El Nino pattern would be eastern-based, so watch out and be ready for a possible second extremely wet winter in 23/2024.

For those who have been around a while, this setup for El Nino reminds me of 1983 and 1998. And for those who don’t know 1983 had around 85 inches of precipitation up on Mammoth Pass, this year the pass is at 94 inches and growing.


PS: Yes this is all in the fantasy outlook period so things could change, until they do this is my story and I am sticking to it. 🙂

0- 16 Day - EPS 500 Height Anomaly
Jet Stream Wind Speeds at 300 hPa

Long Range Seasonal ECM Model from Early March – Next run on this Model is April 3rd

ENSO Outlook – Updated on April 3rd
El Nino Forecast - Mammoth Weather

Mammoth Mountain and Eastern Sierra Weather Posts