Mammoth Mountain Snowfall Data & Powder Probability

Snowfall patterns over the last decade

Across ERA5 reanalysis snowfall records from 2015 to 2025, Mammoth Mountain's November-through-April ski season averages 657cm (259 inches) of snowfall, with another roughly 38cm spread across the shoulder months. March is the heaviest calendar month in the 10-year average at 147.0cm, effectively tied with January at 146.5cm, followed by February at 136.8cm and December at 119.5cm. November builds the base at 61.8cm and April closes the season at 45.7cm. Measured by powder probability — the chance of a week with at least 15cm of fresh snow — March leads at 52%, ahead of January at 47%, February at 43%, December at 39% and November at 32%, so any week from mid-December through late March has historically been a coin-flip or better for fresh powder.

Year-to-year variability at Mammoth is extreme even by Sierra Nevada standards. January snowfall in the 10-year record ranges from just 1.4cm in the driest winter to 510.7cm in the wettest — a roughly 360-fold spread on a single calendar month. February swings between 5.5cm and 376.0cm, March between 24.6cm and 385.8cm, and December between 8.3cm and 365.5cm. This is the signature of California's atmospheric-river-driven winters: a season is often defined by whether a handful of major storm cycles connect, and two consecutive years at the same week can deliver wildly different snow. The multi-year baseline above is much more useful for planning a trip than any single-day Mammoth snow report.

In the context of the Sierra Nevada resorts tracked here, Mammoth's 695cm (274 inches) annual average is the heaviest, just ahead of Palisades Tahoe (Squaw Valley) at 662cm and well above Heavenly's 454cm on the south shore of Lake Tahoe. The gap is concentrated in midwinter: Mammoth's January (146.5cm) and March (147.0cm) totals are both close to Squaw's, but Mammoth's higher summit elevation (3,369m vs 2,745m) tends to preserve snow quality later into spring, and its mid-March powder probability of 52% is the highest of any month at any tracked California resort. For peak powder odds the late-December through late-March window concentrates the highest hit rate; for maximum total accumulation, January and March have historically been the two biggest months in the record.

Snow & Weather Conditions

We use 10 years of historical data to help you plan — not a live snow report.

Sierra Nevada storms deliver heavy, moisture-rich "Sierra cement" snowfall. When cold fronts align, the result is deep dumps that can exceed a metre in a single storm cycle. The high elevation ensures a cold, consistent climate that favours natural snow preservation. Storms frequently deliver generous totals, and the altitude keeps the snowpack dense and skiable throughout the core winter months. Most winters deliver 6-10 metres of cumulative snow, compressing into a 2-metre-plus base by the middle of the season.

Best Time to Ski

The best time to ski at Mammoth Mountain is March and January, with 147cm average snowfall and 52% powder probability. Based on 10 years of historical snowfall data from PowderDays. The season stretches from late November to April, though Mammoth Mountain often stays open into June or even July. PowderDays' historical tool lets you compare precipitation patterns and find the best travel windows.

Powder Probability by Month

Chance of 15cm+ fresh snow in any given week (10 years of data):

• Nov32%
• Dec39%
• Jan47%
• Feb43%
• Mar52%
• Apr23%

10-Year Snow History

What Makes It Special

Diverse terrain from gentle groomers to gnarly cliffs and wind-loaded chutes, plus some of North America's best terrain parks. California ski culture combines outdoor athleticism with West Coast style — expect craft coffee, farm-to-table dining, and stunning Lake Tahoe views.