Data Sources & Telemetry Transparency

SnowBase is committed to 100% data provenance and algorithmic transparency. Here is how we ingest, validate, and display snow telemetry.

🕒 Static directory snapshot last rebuilt: October 5, 2026 at 10:39 AM UTC. Live telemetry fetches on page visit.

1. Primary Ingested Data Sources

USDA NRCS Air and Water Database (AWDB / SNOTEL)

Coverage: Western US Mountain States & Alaska (~900 automated stations).

Elements Ingested: SNWD (Snow Depth), WTEQ (Snow Water Equivalent), PREC (Precipitation Accumulation), and TOBS (Observed Air Temperature).

Update Frequency: Queried daily during automated pipeline builds with hourly caching.

NOAA NCEI GHCN-Daily (Global Historical Climatology Network)

Coverage: Midwest, Great Lakes, Northeast, and Eastern snowmobile networks.

Elements Ingested: SNWD (Daily Snow Depth), SNOW (Daily Snowfall), TMAX, TMIN.

Update Frequency: Daily summaries synchronized every 24 hours.

Open-Meteo High-Resolution Numerical Weather API

Coverage: Global atmospheric grid (HRRR, GFS, ECMWF ensemble models).

Elements Ingested: 7-day hourly snowfall sum, 2m air temperature, wind velocity, gust factor, and freezing level elevation.

Update Frequency: Hydrated on demand in client browser with a 30-minute local cache.

2. "Measured" vs. "Modeled" Distinction

Every snow depth metric on SnowBase is explicitly labeled:

  • Measured indicates physical observation from an ultrasonic ground sensor or official observer snow stick.
  • Modeled indicates high-resolution numerical atmospheric simulation output used when physical sensors are offline or in areas between physical stations.

Data Provenance & Attribution

SnowBase synthesizes public domain meteorological telemetry and open spatial datasets. We acknowledge and credit:

  • USDA NRCS AWDB / SNOTEL: Automated Snow Telemetry mountain stations (Western US).
  • NOAA NCEI GHCN-Daily: Global Historical Climatology Network snow reports (Midwest, Northeast).
  • Open-Meteo API: High-resolution numerical weather forecasts (Non-commercial open tier).
  • National Weather Service (NWS): Active meteorological warnings and bulletins.
  • OpenStreetMap Contributors: Geographic and trail coordinates under ODbL license.

SnowBase is an independent public tool and is not affiliated with the USDA, NOAA, or NWS.