Snow Water Equivalent Dataset

376,964

Observations

851

Series

851

Subjects

1963–2026

Period covered

What this looks like

One real series from the dataset, and real rows from the head of its published extract. Neither is a mock-up: the rows below are the same rows, unchanged, that are in the file you would download.

Snow water equivalent at Lick Creek

The longest single series this dataset holds — 756 monthly values, one of 851. Drawn from 600 of them, evenly spaced across the record. The dataset is not this chart.

Drawn to show the shape and resolution of what the dataset contains, not to make a point about Lick Creek. Gaps are breaks, never interpolated.

View the data behind this chart

240 of 600 periods, evenly spaced across the record. Every value is in the download and the API; a table of all 600 would be longer than this page and unusable with a screen reader.
Period	Lick Creek (mm)
1963.75	0
1964.0833333333333	251
1964.25	486
1964.5833333333333	0
1964.8333333333333	46.8
1965.0833333333333	350
1965.3333333333333	200
1965.6666666666667	0
1965.8333333333333	18.8
1966.1666666666667	227
1966.4166666666667	0
1966.6666666666667	0
1966.9166666666667	89.3
1967.25	479
1967.4166666666667	0
1967.75	5.49
1967.9166666666667	164
1968.25	451
1968.5	0
1968.8333333333333	54.2
1969	170
1969.3333333333333	11.6
1969.5	0
1969.8333333333333	93.6
1970.0833333333333	298
1970.3333333333333	429
1970.5833333333333	0.492
1970.9166666666667	183
1971.0833333333333	335
1971.4166666666667	0
1971.6666666666667	0.593
1971.9166666666667	123
1972.1666666666667	261
1972.5	0
1972.6666666666667	0.169
1973	166
1973.1666666666667	285
1973.5	0
1973.75	6.39
1974.0833333333333	179
1974.25	426
1974.5833333333333	0
1974.75	4.18
1975.0833333333333	333
1975.3333333333333	577
1975.5833333333333	0
1975.8333333333333	79.4
1976.1666666666667	428
1976.3333333333333	140
1976.6666666666667	0
1976.9166666666667	105
1977.1666666666667	396
1977.4166666666667	0
1977.75	10.00
1977.9166666666667	94.1
1978.25	126
1978.4166666666667	0
1978.75	4.92
1979	167
1979.3333333333333	61.4
1979.5	0
1979.8333333333333	37.8
1980	160
1980.3333333333333	10.3
1980.5833333333333	0
1980.8333333333333	65.6
1981.0833333333333	213
1981.4166666666667	0
1981.5833333333333	0
1981.9166666666667	126
1982.1666666666667	317
1982.4166666666667	1.86
1982.6666666666667	0.593
1983	133
1983.1666666666667	239
1983.5	0
1983.6666666666667	2.03
1984	143
1984.25	342
1984.5833333333333	0
1984.8333333333333	51.9
1985.0833333333333	233
1985.4166666666667	0
1985.5833333333333	0
1985.9166666666667	96.7
1986.0833333333333	200
1986.4166666666667	0
1986.6666666666667	0
1987	147
1987.1666666666667	208
1987.5	0
1987.6666666666667	0
1988	129
1988.25	317
1988.5	0
1988.75	0.082
1989.0833333333333	186
1989.25	266
1989.5833333333333	0
1989.8333333333333	55.5
1990.0833333333333	226
1990.3333333333333	84.4
1990.6666666666667	0
1990.8333333333333	56.5
1991.1666666666667	274
1991.3333333333333	224
1991.6666666666667	1.52
1991.9166666666667	114
1992.25	219
1992.4166666666667	0.085
1992.75	14.3
1992.9166666666667	103
1993.25	258
1993.5	0
1993.75	4.10
1994	128
1994.3333333333333	13.3
1994.5	0.082
1994.8333333333333	73.5
1995.0833333333333	208
1995.3333333333333	234
1995.5833333333333	0
1995.9166666666667	97.3
1996.0833333333333	168
1996.4166666666667	0
1996.6666666666667	0.508
1996.9166666666667	163
1997.1666666666667	385
1997.5	0
1997.6666666666667	0.254
1998	109
1998.1666666666667	214
1998.5	0
1998.75	3.69
1999.0833333333333	179
1999.25	294
1999.5833333333333	0
1999.75	0
2000.0833333333333	149
2000.3333333333333	43.3
2000.5833333333333	0
2000.8333333333333	32.3
2001.1666666666667	178
2001.3333333333333	41.4
2001.6666666666667	0.339
2001.9166666666667	40.6
2002.1666666666667	211
2002.4166666666667	0
2002.75	3.20
2002.9166666666667	61.4
2003.25	316
2003.4166666666667	0
2003.75	1.72
2004	151
2004.3333333333333	10.3
2004.5	0
2004.8333333333333	41.7
2005	104
2005.3333333333333	83.0
2005.5833333333333	0
2005.8333333333333	57.6
2006.1666666666667	225
2006.4166666666667	0
2006.75	25.0
2006.9166666666667	76.9
2007.25	285
2007.4166666666667	1.86
2007.75	4.67
2008	109
2008.25	327
2008.5	0
2008.8333333333333	8.55
2009	128
2009.3333333333333	218
2009.5833333333333	0
2009.8333333333333	50.9
2010.0833333333333	145
2010.4166666666667	0.508
2010.5833333333333	0
2010.9166666666667	115
2011.0833333333333	202
2011.4166666666667	36.2
2011.6666666666667	0
2012	170
2012.1666666666667	261
2012.5	0
2012.6666666666667	0
2013	106
2013.25	270
2013.5	0
2013.75	11.7
2014.0833333333333	205
2014.25	441
2014.5833333333333	0
2014.8333333333333	21.1
2015.0833333333333	176
2015.3333333333333	28.8
2015.6666666666667	0
2015.8333333333333	31.9
2016.1666666666667	205
2016.3333333333333	55.8
2016.6666666666667	0
2016.9166666666667	68.3
2017.25	161
2017.4166666666667	0
2017.75	5.98
2017.9166666666667	112
2018.25	365
2018.5	0
2018.75	9.26
2019	136
2019.3333333333333	103
2019.5	0
2019.8333333333333	72.1
2020.0833333333333	223
2020.3333333333333	150
2020.5833333333333	0
2020.9166666666667	49.4
2021.0833333333333	185
2021.4166666666667	0
2021.5833333333333	0
2021.9166666666667	58.1
2022.1666666666667	173
2022.5	0
2022.6666666666667	0
2023	157
2023.1666666666667	292
2023.5	0
2023.75	2.79
2024	70.1
2024.25	184
2024.5833333333333	0
2024.75	4.01
2025.0833333333333	227
2025.3333333333333	127
2025.5833333333333	0
2025.8333333333333	3.22
2026.1666666666667	123
2026.3333333333333	1.88
2026.6666666666667	0.254

Sample rows

12 of 470,842 rows Taken from the start of observations-snow-ice-us-nrcs-snotel.csv. These are sample rows, not the dataset.

Sample rows from the Snow Water Equivalent Dataset extract
`metric_id`	`subject_id`	`subject_kind`	`value`	`censored`	`censor_operator`	`censor_threshold`	`censor_limit`	`censor_reported`	`unit`	`period_start`	`period_end`	`period_kind`	`basis`	`confidence`	`source_id`	`source_ref`	`qualifier`	`superseded`	`retrieved`
snow-water-equivalent	snotel-1000-or	geography	4.424516	—	—	—	—	—	mm	2000-10-01	2000-10-31	month	aggregated	high	us-nrcs-snotel	SNOTEL station 1000:OR:SNTL, snow water equivalent	—	—	2026-10-01
snow-water-equivalent	snotel-1000-or	geography	32.596667	—	—	—	—	—	mm	2000-11-01	2000-11-30	month	aggregated	high	us-nrcs-snotel	SNOTEL station 1000:OR:SNTL, snow water equivalent	—	—	2026-10-01
snow-water-equivalent	snotel-1000-or	geography	153.710968	—	—	—	—	—	mm	2000-12-01	2000-12-31	month	aggregated	high	us-nrcs-snotel	SNOTEL station 1000:OR:SNTL, snow water equivalent	—	—	2026-10-01
snow-water-equivalent	snotel-1000-or	geography	267.355484	—	—	—	—	—	mm	2001-01-01	2001-01-31	month	aggregated	high	us-nrcs-snotel	SNOTEL station 1000:OR:SNTL, snow water equivalent	—	—	2026-10-01
snow-water-equivalent	snotel-1000-or	geography	366.757857	—	—	—	—	—	mm	2001-02-01	2001-02-28	month	aggregated	high	us-nrcs-snotel	SNOTEL station 1000:OR:SNTL, snow water equivalent	—	—	2026-10-01
snow-water-equivalent	snotel-1000-or	geography	448.187097	—	—	—	—	—	mm	2001-03-01	2001-03-31	month	aggregated	high	us-nrcs-snotel	SNOTEL station 1000:OR:SNTL, snow water equivalent	—	—	2026-10-01
snow-water-equivalent	snotel-1000-or	geography	448.902667	—	—	—	—	—	mm	2001-04-01	2001-04-30	month	aggregated	high	us-nrcs-snotel	SNOTEL station 1000:OR:SNTL, snow water equivalent	—	—	2026-10-01
snow-water-equivalent	snotel-1000-or	geography	139.863871	—	—	—	—	—	mm	2001-05-01	2001-05-31	month	aggregated	high	us-nrcs-snotel	SNOTEL station 1000:OR:SNTL, snow water equivalent	—	—	2026-10-01
snow-water-equivalent	snotel-1000-or	geography	0	—	—	—	—	—	mm	2001-06-01	2001-06-30	month	aggregated	high	us-nrcs-snotel	SNOTEL station 1000:OR:SNTL, snow water equivalent	—	—	2026-10-01
snow-water-equivalent	snotel-1000-or	geography	0	—	—	—	—	—	mm	2001-07-01	2001-07-31	month	aggregated	high	us-nrcs-snotel	SNOTEL station 1000:OR:SNTL, snow water equivalent	—	—	2026-10-01
snow-water-equivalent	snotel-1000-or	geography	0	—	—	—	—	—	mm	2001-08-01	2001-08-31	month	aggregated	high	us-nrcs-snotel	SNOTEL station 1000:OR:SNTL, snow water equivalent	—	—	2026-10-01
snow-water-equivalent	snotel-1000-or	geography	0	—	—	—	—	—	mm	2001-09-01	2001-09-30	month	aggregated	high	us-nrcs-snotel	SNOTEL station 1000:OR:SNTL, snow water equivalent	—	—	2026-10-01

Download these rows as CSV — the same twelve, with the column header, for testing a loader before committing to the full file.

Methodology

Collected from the automated SNOTEL network, where each station weighs the snowpack on a pressure pillow every day. Hydrionis reduces the daily record to monthly means, as it does reservoir storage and for the same reason: snow water equivalent is a storage quantity, and what is held in the snowpack this month is the same kind of fact as what is held in the reservoir this month. A month is published only where the station reported on at least twenty of its days. Inches are converted to millimetres and the publisher unit is recorded alongside. The same service publishes a second network of manual snow courses whose records reach back to 1910; those are a different measurement — a person taking cores near the first of the month — and are deliberately not mixed into this record.

What this dataset cannot tell you

Read before relying on these figures

A value of zero is a measurement, not a gap: for most of these stations the snowpack is gone by July and the instrument reports that it is. Reading those months as absence would remove the very values that show when the melt finished.
This is a point measurement on a mountain, not a catchment average. A single pressure pillow can miss drifting and wind scour, and a station is not the snowpack of the basin around it.
Stations sit where snow reliably accumulates, which is high and often north-facing. The network describes mountain snowpack and not the lowlands the meltwater runs into.
Monthly means smooth a quantity that can change sharply in a warm week. The peak of a snowpack, and the date it melted out, are not recoverable from a monthly mean alone.
Coverage is the western United States and Alaska. There is no equivalent record here for the Alps or Fennoscandia, where Hydrionis holds its deepest river records.

Coverage

Subjects	Automated snow monitoring stations in the western United States and Alaska — 851 held
Period	1963–2026
Units	mm
Update cadence	Monthly
Identifier	`snow-water-equivalent` v1.0.0

Fields

Data dictionary →

Every metric this dataset carries, with the unit it is stored in and the geography level it is reported at. Full definitions are in the data dictionary.

Identifier	Field	Unit	Reported at
`snow-water-equivalent`	Snow water equivalent The depth of water that would result if a snowpack melted completely — the water actually stored as snow.	mm	monitoring-station, grid-cell

Rights and access

Licence position

Open. Derivative use true; redistribution true; commercial reuse true.

Applies to material authored by US federal agencies. Third-party material carried within a federal product may be separately protected.

Permitted uses

Public display
Derived analysis
API delivery
Bulk download
Commercial use

Available to: Public, Developer, Research, Professional, Enterprise. These follow from the rights of the contributing publishers, not from a Hydrionis pricing decision — no access tier can widen what a publisher withheld.

Contributing sources

United States Department of Agriculture, Natural Resources Conservation Service — SNOTEL and snow course network — snow water equivalent (US Government work — public domain)

Attribution and citation

Cite and reuse →

Two different obligations, deliberately kept apart. One is a condition of somebody else's licence; the other is a request Hydrionis has no standing to enforce.

Suggested citation for Hydrionis

Hydrionis (2026), Snow Water Equivalent Dataset, version 1.0.0, accessed 2026-10-05, hydrionis.com/data/datasets/snow-water-equivalent/

Cite Hydrionis where you rely on the compilation, the normalisation, the eligibility judgements or a chart. Where you use an unmodified published value, the publisher’s attribution is the one that is required; crediting Hydrionis as well is welcome and is not something Hydrionis can require of you.

Recommended, not required. Hydrionis does not claim rights over unmodified public data it relayed, and doing arithmetic on somebody else’s measurements does not make them Hydrionis’s. Cite the version and the access date: Snow Water Equivalent Dataset changes as publishers release and as methods are revised, and a citation without both cannot be checked later. Full guidance is on cite and reuse.

None of the contributing licences requires attribution. Crediting the publishers is still good practice and they are listed above.

Changelog

Version 1.0.0 — 2026-08-31

First release: the water in the snowpack, where Hydrionis previously held only its depth.

Additions

Monthly snow water equivalent for 847 stations, the earliest from 1963.

Use this data

Download snow-ice observations from NRCS (470,842 rows) (CSV)
Machine-readable JSON /api/v1/datasets/snow-water-equivalent.json
How to cite this, and who you must credit
How these figures were produced
Request this at a different scale, format or geography

Every bulk extract ships with a companion metadata file carrying this dataset’s version, its sources, their licences, the attribution you are required to give and the suggested citation — so the terms travel with the file rather than staying on this page.

About this data

The fields a professional user needs to judge whether this is fit for a particular purpose. Deliberately not a score.

About this data

Everything below is a property of the data rather than a rating of it. There is deliberately no single confidence score: how much a gap matters depends on what you are about to do with the series, and only you know that.

Source	United States Department of Agriculture, Natural Resources Conservation Service — SNOTEL and snow course network — snow water equivalent · US Government work — public domain
How the values came to exist	Mixed across the series — the basis is recorded on every individual value.
Period held	1963–2026
Known gaps	A value of zero is a measurement, not a gap: for most of these stations the snowpack is gone by July and the instrument reports that it is. Reading those months as absence would remove the very values that show when the melt finished. This is a point measurement on a mountain, not a catchment average. A single pressure pillow can miss drifting and wind scour, and a station is not the snowpack of the basin around it. Stations sit where snow reliably accumulates, which is high and often north-facing. The network describes mountain snowpack and not the lowlands the meltwater runs into.
Continuity	Version 1.0.0, released 2026-08-31. 1 recorded version; breaking changes and corrections are listed in the changelog above.
Last read from the publisher	2026-10-01 · publisher updates monthly
Redistribution	Permitted by the upstream licences
Commercial reuse	Permitted by the upstream licences. No Hydrionis access tier can widen this.
Methodology	How this was produced