Precipitation, water-year to date (SNOTEL): methodology
Provenance for the series on Precipitation, water-year to date (SNOTEL). This page has its own URL so it can be cited alongside a figure.
- Source
- USDA NRCS SNOTEL
- Dataset identifier
- snotel_precipitation
- Update cadence
- Monthly, updated daily upstream
- Unit
- inches
- Coverage
- 58 series · 1978-10-01 to 2026-09-01
- Vintage published here
- 2026-10-30
Accumulated precipitation in inches at USDA NRCS SNOTEL stations, from the Air and Water Database (AWDB).
This series accumulates through the water year and resets on 1 October. It is
not monthly precipitation. At Bear Creek the September 2025 value is 31.7 inches
and the October 2025 value is 3.6, because October starts water year 2026 from
zero. Differencing consecutive months within a water year gives that month's
precipitation; differencing across the October boundary gives nonsense. If you
want monthly totals, use our noaa_precipitation series instead, which is
monthly by construction.
One station, not a county, and the end-of-month value rather than a monthly average — the same caveats as snow water equivalent, which documents them at length.
Flags are carried through from AWDB as preliminary, estimated and
suspect.
Revisions and vintages
Every observation we store carries the date it was published, and a revision lands as a new vintage rather than overwriting the old one. The figures on this site are the most recent vintage, stamped above; a figure you cited earlier stays retrievable even after the source restates it.
The full series, including the flag and vintage of every value, is in the CSV.