Powder Forecast – Friday, March 27th, 2026
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 3/28 = 0”
Sun 3/29 = 0”
Mon 3/30 = 0”
Tue 3/31 = 0 – 1”
Wed 4/1 = 0 – 3”
Thu 4/2 = 1 – 5”
Fri 4/3 = 0 – 3”
Sat – Mon 4/4 – 4/6 = 0”
March Snowfall = 1”
March Forecast = 1 – 2”
Detailed 4-day Snowfall Forecast:
Sat 3/28 through Mon 3/30 – No snowfall expected all days except for a slight chance for light snowfall late Monday night.
Tue 3/31– Chance for light snowfall to develop during the day and continue overnight. Snow levels around 8000-9000 feet. Accumulations 0 – 3” by Wednesday AM.
Forecast Summary:
Short Term (Days 1 – 4):
The current infrared satellite image (below) this afternoon shows high pressure is over the Southwest, and a weak low-pressure system just off the Central Coast is spreading clouds across the state.
The high-pressure ridge will only weaken slightly over the weekend (image below) for continued fair weather and spring conditions across most of the mountain under slightly cooler temperatures.
Dry weather will continue into Monday, with a chance of light snowfall developing late Monday night and Tuesday from an approaching weak low-pressure system (image below). The latest GFS and ECM model runs wash out the low upon landfall, but a number of ensembles keep it together, resulting in light snowfall. The current forecast calls for a chance of light snow starting late Monday night and continuing through Tuesday, with snow levels rather high, in the 8-9000-foot range. The best-case scenario would be a few inches by Wednesday morning, but confidence in that solution is low right now.
Long Range (Days 5+):
The longer-range guidance has now come into better agreement that a change back to winter temperatures will occur next week, but has backed off considerably since the last post on potential snowfall amounts. The trend upon the deterministic models has been drier almost every run with the ensemble means also trending drier. So what looked so promising early in the week is now looking like a typical spring storm.
The latest 12z run of the ECMWF moves a rather deep upper-level low pressure system into CA on Wednesday and into Thursday (image below). The models have trended farther northward with the passage of the low and also do not dig the low southward off the coast before landfall. That means little or no southwest flow out ahead of the trough passage that is usually a necessary ingredient for good snowfall events.
The 12z deterministic models are rather dry outside of the Canadian (image below) that still has over an inch liquid or a foot of snowfall. The ECM (two images below) and GFS (three images below) are showing about a tenth of an inch or mostly just dust on crust amounts.
The ensemble models are wetter with the NBM (image below), ECM EPS (two images below), and GFS (three images below) all showing around 0.65-0.75” liquid or enough for at least low-end powder conditions. Timing for best chance for snowfall would be Wednesday PM/night. Current forecast leans toward the ECM/NBM solutions for at least a few inches, although there is a lot of caution that the dry deterministic models may be right.
The ECMWF model has high pressure rebuilding over the state over the following weekend (image below) for a return to fair weather and seasonable temperatures. That model is dry for the rest of its forecast period.
The ECM EPS develops a weak longwave trough over the interior West (image below) over the following week. The main effect would only be cooler temperatures and breezy winds as that pattern supports inside slider type weather systems. The ECMWF EPS forecast for April does have about 2” of liquid for the month (image below), so hopefully there will be a late season surprise. WG
