Powder Forecast – Friday, February 7th, 2025
Ted Schlaepfer CCM —- Mammoth Mountain WeatherGuy
Snowfall forecasts are valid at the Sesame snow course (Main Lodge) for the prior 24 hours as reported in the 6-7 AM morning snow report.
**Snowfall forecast confidence ranges from very low (1) to very high (5)
Sat 2/8 = ~1”
Sun 2/9 = 0”
Mon 2/10 = 0”
Tue 2/11 = 0”
Wed 2/12 = 0”
Thu 2/13 = 6 – 9”
Fri 2/14 = 24 – 36”
Sat – Mon 2/15 – 2/18 = 3 – 6”
February Snowfall = 21”
February Forecast = 75 – 95”
Detailed 4-day Snowfall Forecast:
Sat 2/8 through Mon 2/10 – No snowfall expected all days
Tue 2/11 – No snowfall expected during the day, slight chance for light snow showers overnight, no accumulation expected.
Forecast Summary:
Short Term (Days 1 – 4):
The current infrared satellite image (below) this afternoon shows that the storm system that produced the snowfall yesterday and last night has now mostly moved eastward out of CA with just some lingering snow showers that will end this evening.
A weak trough of low pressure will remain across the interior West through the weekend and into early next week. Mammoth will see weak northerly jet stream flow that will keep temperatures seasonably cold.
An upper-level short-wave trough will move into CA from the North on Tuesday (image below) and that will produce even colder temperatures and some gusty winds. It could also produce some light snow showers Tuesday night and into Wednesday, but no accumulation is currently expected. Otherwise, dry weather is forecast through early next week.
Long Range (Days 5+):
The longer-range guidance is still favoring a good storm pattern for Mammoth toward the end of next week, although just how good it will end up is still questionable. There could be another weak storm early the following week with the longer-range guidance trending drier for the third week of the month before suggesting the pattern could get active again end of February and into March.
The next storm system is expected to move into the state around Thursday per the 12z ECM (image below) with the trough passage occurring on Friday (two images below). The ECM model is deeper versus the GFS and Canadian that are portraying a slightly weaker version or slightly different orientation. The 12z ECM is also deeper than the ECM EPS mean, so it may be a bit too strong, hopefully not.
That is because the model is forecasting around 7”+ liquid for the event that would easily equate to 4-5 feet of snowfall at Main. The Canadian is showing similar amounts west of the crest (two images below) while the GFS model is the “driest” at around 4” liquid (three images below).
Overall, the models seem to phase an atmospheric river into the jet stream while the trough deepens simultaneously just off the CA coast. Right now, snow levels are forecast to stay in the 7000-7500 range or lower which makes sense with the dynamic cooling counteracting the strong warm advection from a possible AR.
The current forecast follows the ECM EPS mean (image below) that is closer in line with the GFS forecast of around 4”. The GFS ensemble mean (two images below) is showing slightly less and around 3” liquid. Regardless, a couple feet looks probable with a good chance for 3-4 feet at Main over a 2-3 day period. On the upper end, if the ECM has its way, 55” will fall in town (three images below) and 6-7” feet on the mountain, don’t think that will happen though. All the details should be sorted out by the Tuesday posting.
The longer-range guidance is forecast a break over the following weekend before another trough is favored to move into CA early the following weekend. It is currently forecast to affect NorCal and Mammoth may just see the tail end of a cold front for mostly light snowfall. Hopefully that will trend snowier.
The fantasy range guidance is now favoring a dry period for the middle and latter part of that next week. The latest ECM 45-day forecast keeps the mostly dry weather in place for the rest of February, but the GFS and CFS (image below) models suggest some precipitation may move back into CA with normal precipitation for Mammoth. More the reason for it to dump bigtime next week. WG
