Powder Forecast – Tuesday March 18th, 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)
Wed 3/19 = 0”
Thu 3/20 = 0”
Fri 3/21 = 0”
Sat 3/22 = 0”
Sun 3/23 = 0”
Mon 3/24 = 0”
Tue 3/25 = 0”
Wed – Fri 3/26 – 3/28 = 3 – 6”
March Snowfall = 60”
March Forecast = 80 – 90”
Detailed 4-day Snowfall Forecast:
Wed 3/19 through Sat 3/22– No snowfall expected all days.
Forecast Summary:
Short Term (Days 1 – 4):
The current infrared satellite image (below) this afternoon shows high pressure is building into the state today with the low pressure system that produced the snowfall yesterday having moved into Arizona. A weather system off the coast will move toward the coast over the next 36 hours.
The models move that weather system through NorCal on early Thursday and too far northward for any snowfall in Mammoth. It will increase the winds for good wind buff conditions up top Wednesday afternoon and again Thursday. Another weak wave will move through NorCal on late Friday or early Saturday, otherwise it will be a fair and breezy week with that low passage also increasing the wind buff conditions up top.
Long Range (Days 5+):
The longer-range guidance has flipped back a bit to a better scenario for the last part of the month with any dry period now looking short-lived. The models have trended a bit more favorably with the chances for precipitation and powder days extending into early April.
The high-pressure ridge will build into the state more strongly early next week (image below) and it will probably be strong enough for temperatures to get warm enough for spring conditions on most of the mountain.
Changes in the weather pattern back to winter are then favored by the end of the week with the latest ECM run (image below) developing a deep long-wave trough along the West Coast and the jet stream into California. It is not showing a lot of precipitation yet, but that will probably be the first wave of snowfall. The other models are similar, although the GFS is slightly slower with the development of the wet pattern by a day or so.
The models keep the longwave trough set-up along the West Coast through the end of the month (image below) and into the first week of April. The ECM EPS (two images below) is showing enough precipitation at around an inch liquid for powder conditions. Exactly when and how much snowfall will occur is yet to be determined.
The guidance is saying that slightly above normal precipitation will continue through the first week of April (image below) for additional chances for powder conditions. Powder days during April happen almost every year, especially the first half of the month. And let’s hope they happen before Canyon/Ch. 22 closes mid-month. WG
