TL;DR
- Storm total: 18-24 inches across the Wasatch Range, March 6-8, 2026
- Biggest day: March 7 — over 10 inches at Alta and Snowbird
- 1-day forecast accuracy: 82% average (Excellent tier) across 5 Wasatch resorts
- 3-day forecast accuracy: 71% average (Good tier) — issued March 3
- Range containment: 100% — every resort's actual fell within the predicted 10th-90th percentile range
- Bias: -1.8 inches average (slight under-forecast during sustained NW flow)
The Storm
A deep Pacific trough brought persistent northwest flow to the Wasatch Range from March 6-8, 2026. Snow-to-liquid ratios ran in the 12-14:1 range — classic Wasatch density — with storm totals ranging from 15 inches at lower elevations to over 24 inches along the upper ridgeline.
This was one of the best storm cycles of the 2025-26 season and a good test of PowCall's forecasting system.
What We Predicted vs. What Fell
We issued our 3-day forecast for this event on March 3, giving skiers three full days of lead time. Here's how it played out:
Alta
| Metric | PowCall Forecast | SNOTEL Actual |
|---|---|---|
| 3-Day Total | 19.2" (range: 14-26") | 22.1" |
| Best Day | Mar 7: 9.4" | Mar 7: 10.3" |
| Day 1 (Mar 6) | 4.8" | 5.2" |
| Day 2 (Mar 7) | 9.4" | 10.3" |
| Day 3 (Mar 8) | 5.0" | 6.6" |
Verdict: The median prediction was 2.9" low over three days, but the actual fell within the predicted range of 14-26". The 1-day forecast for March 7 (the biggest day) was accurate to within an inch. View Alta's full accuracy history.
Snowbird
| Metric | PowCall Forecast | SNOTEL Actual |
|---|---|---|
| 3-Day Total | 17.5" (range: 12-24") | 20.4" |
| Best Day | Mar 7: 8.8" | Mar 7: 9.7" |
Verdict: Slightly under-forecast on the median, but the actual landed within range. The ensemble spread correctly indicated high uncertainty on the upper end. View Snowbird's forecast.
Brighton & Solitude
Both resorts saw 16-18" over the 3-day period. PowCall predicted 15.2" and 14.8" respectively — within 2" on the median and within range on both. Brighton forecast | Solitude forecast.
Accuracy Scores
For this storm cycle across all 5 Wasatch resorts:
- 1-Day Lead Accuracy: 82% average (Excellent tier)
- 3-Day Lead Accuracy: 71% average (Good tier)
- Range Containment: 100% — every resort's actual snowfall fell within the 10th-90th percentile range
- Bias: -1.8" average (slight under-forecast, typical for sustained NW flow events)
What Worked
Ensemble spread nailed the uncertainty. The 10th-90th percentile range captured every resort's actual total. This is exactly what probabilistic forecasting is designed for — telling skiers "expect somewhere between 14 and 26 inches, with 19 most likely."
Best-day identification was accurate. PowCall correctly identified March 7 as the biggest snow day at every Wasatch resort 3 days in advance.
Orographic correction performed well. The PRISM-calibrated multipliers for NW flow correctly boosted precipitation at Alta and Snowbird relative to lower-elevation stations.
What We'll Improve
Slight systematic under-forecast in strong NW flow. The -1.8" bias during this event suggests the orographic multipliers may be slightly conservative for sustained NW events. We're reviewing historical PRISM data for similar events to recalibrate.
SLR estimation was close but not perfect. We predicted 12:1 SLR on average; actuals suggest closer to 13:1 based on SWE comparisons. One ratio point doesn't sound like much, but across 2" of liquid precipitation, that's an extra 2" of snow.
FAQ
How much snow did Alta get in March 2026?
Alta received 22.1 inches of snow during the March 6-8, 2026 storm cycle, measured by the SNOTEL observation station. This was the biggest storm of the 2025-26 season in the Wasatch.
How accurate was PowCall's forecast for this storm?
PowCall's 1-day forecasts averaged 82% accuracy (Excellent tier) across all 5 Wasatch resorts during this storm. The 3-day forecasts issued on March 3 averaged 71% accuracy (Good tier), and 100% of actual snowfall totals fell within the predicted ranges.
What is SNOTEL and how is it used for verification?
SNOTEL (Snow Telemetry) is a network of automated weather stations operated by the USDA Natural Resources Conservation Service. These stations measure snow water equivalent, snow depth, precipitation, and temperature at mountain locations. PowCall uses SNOTEL data as ground truth to verify every forecast prediction.
Did PowCall predict the storm correctly?
Yes. PowCall identified this as a significant snow event 3 days in advance, correctly predicted March 7 as the biggest day, and all actual snowfall totals fell within the predicted probabilistic ranges. The main miss was a slight under-forecast bias of 1.8 inches.
All accuracy metrics are computed against SNOTEL ground observations and published on each resort's forecast page. View Wasatch accuracy data. Learn more about our forecast methodology.