Snow Briefing · Ski area
Mammoth Mountain Ski Area, CA
Ski area • base 8,546 ft • summit 10,378 ft • NBM 18Z 15 Nov 2026 • issued 19:39Z
The blend has 4.2″ of snow for Mammoth Mountain Ski Area over the next three days, 0.1″ of it in the first 24 hours, and 44.0″ over its ten days. Verdict: plow it.
The next ten days
Plow verdict on the 72-hour total: Plow it
| Horizon | Snow | Range 10–90% | Ice | Chance ≥1″ | Chance ≥6″ |
|---|---|---|---|---|---|
| Next 24 h | 0.1″ | 0.0–0.2″ | 0.00″ | 0% | 0% |
| Next 48 h | 3.8″ | 0.4–6.9″ | 0.00″ | 78% | 18% |
| Next 72 h | 4.2″ | — | 0.00″ | — | — |
| 5 days | 34.8″ | — | — | — | — |
| 7 days | 36.6″ | — | — | — | — |
| 10 days | 44.0″ | — | — | — | — |
Snow is the blend's deterministic forecast; the range is its 10th to 90th percentile and the chances are its own exceedance probabilities. Ice is freezing-rain accretion.
Day by day
| Climate day (12Z–12Z) | Snow | 90th pct | Chance ≥1″ | Chance ≥6″ |
|---|---|---|---|---|
| Tue 17 Nov | 3.7″ | 6.9″ | 78% | 18% |
| Wed 18 Nov | 0.0″ | — | — | — |
| Thu 19 Nov | 16.2″ | — | — | — |
| Fri 20 Nov | 14.2″ | — | — | — |
| Sat 21 Nov | 0.7″ | — | — | — |
| Sun 22 Nov | 1.0″ | — | — | — |
| Mon 23 Nov | 1.8″ | — | — | — |
| Tue 24 Nov | 0.7″ | — | — | — |
| Wed 25 Nov | 4.3″ | — | — | — |
Climate days run 12Z to 12Z, the window the NWS national snowfall analysis scores. Percentiles and chances are available for the first two days.
Two weeks out · ECMWF ensemble
| By | p10 | Median | p90 | Members ≥1″ | Members ≥6″ |
|---|---|---|---|---|---|
| Day 3 | 1.0″ | 1.7″ | 3.3″ | 88% | 0% |
| Day 5 | 9.7″ | 17.8″ | 33.0″ | 100% | 98% |
| Day 7 | 10.1″ | 19.7″ | 34.9″ | 100% | 98% |
| Day 10 | 12.1″ | 23.1″ | 40.1″ | 100% | 100% |
| Day 15 | 17.1″ | 30.2″ | 51.6″ | 100% | 100% |
ECMWF open data, 50 perturbed members at 0.25°, snow at a fixed 10:1 ratio, run 00Z 15 Nov. Cumulative from the run.
Density, level and trend
| Density at 48 h | 4.4 lb/ft³ |
| Load at 48 h | 1.4 lb/ft² |
| Snow-to-liquid ratio at 48 h | 14:1 |
| Snow level at 24 h / 48 h | — / 3,957 ft |
| Freezing rain chance, 48 h | 0% |
| Trend | up 1.1″ vs the previous run (48 h) |
How good is this forecast?
The blend's day-1 snowfall this season, scored against the NWS national snowfall analysis: mean absolute error 1.12″, bias −0.21″, critical success index at 6″ 0.06 over 71 scored days. Last scored day: 14 Nov 2026.
Nearby briefings
forecastflakes.com/products/mammoth-mountain-ski-area-ca · NWS National Blend of Models · ECMWF open data · © 2026 Forecast Flakes · not an official warning source