Mammoth Mountain Weather Forecast & Discussion

February 8th, 2023 @ 6 PM –  A ridge of high pressure will continue to influence the weather into Friday with dry conditions and mostly clear skies.

By later Friday there will be a cut-off low that will start to change up the weather. The track of that low is just offshore with the system dropping south all the way past the US border and then tracking eastward.

The weather effects on Mammoth Mountain will be increasing SW winds on Friday with snow showers on Saturday with 1-2 inches of snow possible at this time. The low will be far enough to the south of the area by Sunday resulting in clear skies over the area.

If you’re going to be out on the hill on Thursday expect sunny skies, with temperatures in the upper 30s to lower 40s by mid-day. Light winds should be switching over the E / NE to the SW with winds speeds in the 5-15 MPH range with a bit stronger gusts up top.

On Friday expect sunny skies once again with temperatures in the low to mid-30s. The SW wind flow will be back at 15 to 25 mph, then increasing to 25 to 35 mph in the afternoon. Winds could gust as high as 45-55 mph over higher elevations.

For Saturday expect snow showers and cold temperatures with highs in the upper teens to mid-twenties. There will be more windy conditions with a northeast wind of 10 to 20 mph increasing to 15 to 25 mph in the afternoon. Winds could gust as high as 30-40+ mph over the mid and upper mountain.

Snowfall amounts look to be in the 1-3 inch range. However a change in the track of the cut-off low could quickly change that amount to zero or possibly more snowfall.

By Sunday skies should clear out and temperatures will be in the upper 20s to low 30s across the hill.

The next chance for a series of wet storms is slated for President’s Holiday week according to the GEFS / GFS US Models. However, the EPS / ECM Models don’t agree so we will have to wait and see what might be coming our way.

I will update the long-range forecast information down the page again on Saturday.

Snowman

Mammoth Mountain 10-Day Outlook

2-5-23 – By Monday the area of low pressure that is in the area today will be to the SSE of Mammoth. That will result in a chilly day with gusty North winds over the Mountain.

By Tuesday a ridge of high pressure will start to rapidly build into the area bringing with it a quick warming trend during the day. Winds will turn to the NW at light to moderate speeds.

For Wednesday the wind flow will be out of the west with light wind speeds, and temperatures will be into the upper 30s to mid-40s out on the hill.

Temperatures in that range will create some mid-day melting snow on the lower Little Eagle runs that get direct sun.

Most of the terrain on the mountain will stay in a winter snowpack form as the sun is still at mid-winter heights.

On Thursday the ridge is slowing progressing with the ridge peaking over the Mammoth area on this day. Winds at this point look to move back to the NW helping to keep temperatures from increasing anymore.

By Friday Mammoth will still be under the influence of the ridge but the ridge axis will now be to the east of the area. You can see the approaching cut-off low off the pacific northwest coast in this image

For Saturday the Cut Off Low will be just off the coast and should be kicking up some SW winds for a possible sugary wind buff session. However, this is a cut-off low the track it takes by next Saturday is in question.

Fantasy Period Outlook for Days 7-10 – The weather during these days will be influenced by the unknown path of the cut off low and then the inside slider that is forecast to follow the cut off low. You can see how the EPS ensembles handles the 2 lows below.

11-16 Day Super Fantasy Long-Range Discussion

2-5-23 The EPS Ensemble below shows the inside slider from day 8 dropping to the SE. A second low would be off the west coast by day 12/13 so maybe there could be a better chance of getting some moderate snowfall out on Mammoth Mountain.

Longer Range Weather Data

FYI (Long Range Weather Data is not a forecast)  – Looking at the latest run of the EPS 45 day Ensemble Mean the models have backed off on bringing in the next AR set up for later February into March.

ENSO Outlook

Mammoth Mountain and Eastern Sierra Weather Posts

Mammoth Mountain Weather Forecast & Discussion

February 1st, 2023 @ 3:34 PM

Mammoth Weather Summary:  On Thursday there will be increasing clouds during the day as a very weak system is moving to our north. By Friday morning expect some cloudy skies with a few possible light snow showers early on.

The next system will be more moderate in strength and have some decent moisture. As of now it appears there could be in the area of 6-12 inches of snow from the Sunday system.

By Monday the low has moved to the SE of the area and skies will clear out fast for what looks like a possible bluebird powder day up top.

This does look like the snow producer that is needed to clean up the rest of the NE wind snow sculptures you see up top in spots right now.

If you’re going to be out on the hill on Thursday expect pt cloudy skies with increasing clouds during the afternoon hours with temperatures in the mid to upper 30s. The wind will be out of the SW in the 5-10 MPH range with gusts into the 15-20 MPH range over the higher elevations. 

On Friday expect cloudy skies with a few possible snow showers early then clearing to pt cloudy skies with highs in the upper 20s to low 30s in the Main Lodge area. Winds will be southwest @ 20-25 mph, with gusts as high as 45-55 mph over the mid and upper mountain. 

For you Weekend Warriors, expect sunny skies to start the day on Saturday with increasing clouds during the PM hours with temperatures in the low to mid 30s. Wind will be moderate out of the SW.

Sunday looks to offer up snow Moderate to Heavy at times with day times highs in the mid to upper 20s. Snowfall accumulations during the day look to be in the 3-6+ inch range.

Snowman

PS: Scroll down the page for the full Mammoth Mountain Weather Discussion & Long Range Outlook

NWS Mammoth Mountain Forecast Photo
NWS Mammoth Mountain Forecast Photo

Mammoth Mountain 10 Day Outlook

Below is the EPS Ensemble for the next 10 days. You can see the next weak low that is coming on Friday followed by a moderate system Saturday night into Sunday night. Those two systems will be followed more ridging that lasts right out to Day 10.

ECM 10 Day Outlook

Below is the EPS 24 hour Precipitation Forecast for the next 10 days. The gif shows a very weak system for Friday followed by the moderate system on Sunday that could result in a riders of the storm day on Sunday with a blue bird powder day possible for next Monday.

ECMWF 24 Hour Snowfall Outlook

11-16 Day Fantasy Long-Range Discussion

Beyond the 10-day outlook models are in agreement that there will be some troughing starting to set up out west. How it all develops is in question as the GEFS and EPS Ensembles are not all in agreement at this time. This pattern would bring some snowfall, let’s hope that the pattern west of the Sierra as that would bring much more snowfall.

Longer Range Weather Data

FYI (Long Range Weather Data is not a forecast)  Both the EPS 45 Day Control and the GEFS Ensembles have the area getting wetter the last week of February and into the first week part of March. The GEFS has about 8-10 inches of water with the EPS showing 15-20 inches of water.

Like I have said many times over the years, patterns tend to repeat themselves so maybe there will a mini AR repeat. That far out of course is unreliable at this point in time, but it sure is worth noting seeing that wet of a pattern on the EPS 45.

EPS 45 Day Ensemble Control
GEFS Ensemble Mean
ENSO Outlook

Mammoth Mountain and Eastern Sierra Weather Posts