California Snowpack: Water in the Snow, Station by Station
California is the biggest snowpack audience in the country and the one place where our number and the state’s own may disagree. It is served here through the federal network, including the cooperator snow sensors that mirror the state pillows, and this page says plainly where the two records diverge.
Where California snowpack stands
California snow stations on the map
The California stations, lowest first
A station is one clearing. It reads the snow lying on its own pillow, and that can differ sharply from a slope a mile away and a thousand feet higher. Reading one station against its own past is far more informative than reading two stations against each other, which is why the last column gives each one its own percentile rather than a rank against its neighbours.
Which California basins are carrying the water
The Sierra Nevada is one long ridge intercepting Pacific storms, so California’s water year is decided by a handful of storms rather than by a steady season. A few missing atmospheric rivers is the difference between a full snowpack and an empty one, which is why California numbers swing further year to year than the Rockies do.
The basin names below are the six digit hydrologic units the station records carry, named from the United States Geological Survey boundary dataset. California covers 11 of them across 20 counties. A basin appears once three or more of its stations are reporting.
This day, across the California record
A single percentage tells you where today sits against a thirty year median. It does not tell you whether that is unusual, and the two questions have genuinely different answers: a state can be at 70 percent of median in a year that is nowhere near its worst.
The federal and state California numbers
For station ALP in the American River basin, the federal database and California’s own Data Exchange Center report materially different snow water equivalent for the same day at the same confirmed coordinates: 11.2 inches against 13.92 inches for March 1, 2026, a gap of about 24 percent. It is not a start of day against end of day artefact, because the state figure is above both of the federal ones. We could not explain it and we are not going to split the difference. Separately, some California cooperator stations that exist in the federal station list return no data through it at all while the state serves them normally, so the federal mirror of California is incomplete as well as divergent. Everything on this page is read from the federal network and labelled as such. For the number California itself publishes, go to the Department of Water Resources.
California Department of Water Resources, California Data Exchange Center. Link checked 2026-09-04.
What the agency forecast for California in 2026
This is the completed record of a finished season. The Natural Resources Conservation Service issues seasonal runoff volume forecasts for 14 points in California, monthly through the winter and spring, and each issue supersedes the last. Below are the biggest of those points and how each forecast moved as the snow year revealed itself.
The current runoff forecast is published by the agency; the most recent issue shown here is months old by definition, because the series closes in early summer. For the forecast that applies now, go to the agency, or to NOAA California Nevada River Forecast Center for river stage.
Truckee R at Farad
April 1 to July 31 runoff volume, thousands of acre feet. Normal for that period 225. 8 issues on file for water year 2026.
The bar is the range the agency published at each issue, from the ninety percent exceedence value at the bottom to the ten percent value at the top, with the fifty percent value marked. An exceedence probability is the chance the actual volume exceeds that number, so ninety is the low end and ten is the high end. The fifty percent figure moved from 230 on the January 1 issue to 150 on the April 13 issue, or 102 percent of normal down to 67 percent. Those are the agency’s numbers for a season that has finished; the current forecast is on the agency’s own site.
W Walker R bl L Walker R nr Coleville
April 1 to July 31 runoff volume, thousands of acre feet. Normal for that period 153. 4 issues on file for water year 2026.
The bar is the range the agency published at each issue, from the ninety percent exceedence value at the bottom to the ten percent value at the top, with the fifty percent value marked. An exceedence probability is the chance the actual volume exceeds that number, so ninety is the low end and ten is the high end. The fifty percent figure moved from 150 on the January 1 issue to 86 on the April 1 issue, or 98 percent of normal down to 56 percent. Those are the agency’s numbers for a season that has finished; the current forecast is on the agency’s own site.
W Walker R nr Coleville
April 1 to July 31 runoff volume, thousands of acre feet. Normal for that period 147. 4 issues on file for water year 2026.
The bar is the range the agency published at each issue, from the ninety percent exceedence value at the bottom to the ten percent value at the top, with the fifty percent value marked. An exceedence probability is the chance the actual volume exceeds that number, so ninety is the low end and ten is the high end. The fifty percent figure moved from 144 on the January 1 issue to 91 on the April 1 issue, or 98 percent of normal down to 62 percent. Those are the agency’s numbers for a season that has finished; the current forecast is on the agency’s own site.
Truckee R ab Farad Sidewater
April 1 to July 31 runoff volume, thousands of acre feet. Normal for that period 90. 4 issues on file for water year 2026.
The bar is the range the agency published at each issue, from the ninety percent exceedence value at the bottom to the ten percent value at the top, with the fifty percent value marked. An exceedence probability is the chance the actual volume exceeds that number, so ninety is the low end and ten is the high end. The fifty percent figure moved from 100 on the January 1 issue to 54 on the April 1 issue, or 111 percent of normal down to 60 percent. Those are the agency’s numbers for a season that has finished; the current forecast is on the agency’s own site.
Little Truckee R bl Boca Dam
April 1 to July 31 runoff volume, thousands of acre feet. Normal for that period 72. 8 issues on file for water year 2026.
The bar is the range the agency published at each issue, from the ninety percent exceedence value at the bottom to the ten percent value at the top, with the fifty percent value marked. An exceedence probability is the chance the actual volume exceeds that number, so ninety is the low end and ten is the high end. The fifty percent figure moved from 80 on the January 1 issue to 45 on the April 13 issue, or 111 percent of normal down to 63 percent. Those are the agency’s numbers for a season that has finished; the current forecast is on the agency’s own site.
Little Truckee R bl Stampede Dam
April 1 to July 31 runoff volume, thousands of acre feet. Normal for that period 69. 4 issues on file for water year 2026.
The bar is the range the agency published at each issue, from the ninety percent exceedence value at the bottom to the ten percent value at the top, with the fifty percent value marked. An exceedence probability is the chance the actual volume exceeds that number, so ninety is the low end and ten is the high end. The fifty percent figure moved from 75 on the January 1 issue to 28 on the April 1 issue, or 109 percent of normal down to 41 percent. Those are the agency’s numbers for a season that has finished; the current forecast is on the agency’s own site.
Volumes are in thousands of acre feet, in the units the agency publishes. Each point’s forecast period is printed above its chart, because the period is not the same everywhere: the Southwest runs off earlier and its forecasts are issued for an earlier window. Volumes from different periods are not comparable.
What the California snowpack number shows
The peak date on this page is a median of medians. Across the 111 California stations that publish one, the individual median peak dates span 54 days, from March 2 to April 25. A low station on a south face and a high one in a north facing cirque are in different climates, and averaging them produces a date that describes neither.
9 of the 126 California stations have no 1991 to 2020 median at all, nearly always because they were installed too recently to have thirty years behind them. A station with no normal cannot be a percentage of one, so it appears on the map and in the table with its measurement and no percentage, and it is left out of the state total. The panel at the top of this page prints both counts.
California has 36 federal snow telemetry stations and about ninety cooperator snow sensors mirrored into the same database, which is why its station count looks unlike its neighbours.
How California sits against the rest of the network. Its middle station is at 7,585 ft, against 10,275 ft in Colorado and 1,345 ft in Alaska. Elevation is not a proxy for depth: the deepest packs in the country sit on some of the lowest stations, because a maritime climate delivers far more water per storm than a continental one.
California snowpack FAQ
Snow, melt and what happens after
Avalanche forecasts for the layers inside this same snowpack are issued by named forecasters at the avalanche centres: avalanche forecasts by state.
Sources for this page
- USDA NRCS Air and Water Database, daily snow water equivalent filesfederal, public domain Read 2026-09-04.
One file per calendar day carrying every station’s entire period of record for that day. Measured at 102,474 bytes and 0.17 seconds for September 3 and 192,640 bytes for March 15, keyless and open to any origin. This is the source of every reading on these pages.
- USDA NRCS Air and Water Database REST APIfederal, public domain Read 2026-09-04.
The documented API behind the same database. Used to build the station inventory, to verify that the daily files decode correctly, and as the fallback when the daily files cannot be reached.
- USDA NRCS report generatorfederal, public domain Read 2026-09-04.
The one source that emits NRCS’s own labelled percent of median. Used to prove our figures reproduce the agency’s: all 118 Colorado stations matched exactly on value, median and percentage for March 15, 2026. Too slow to read live, at 8.9 seconds for one state.
- USDA NRCS interactive station mapfederal, public domain Read 2026-09-04.
The agency’s own live map of every station it operates. This is where a reader goes for the official current picture, and every page in this vertical links it.
- USGS Watershed Boundary Datasetfederal, public domain Read 2026-09-04.
NRCS station records carry a bare twelve digit hydrologic unit code and no name. The basin names on these pages come from the USGS boundary dataset, which named all 96 six digit basins in the station inventory.
- California Department of Water Resources, California Data Exchange Centerstate agency, linked not reproduced Read 2026-09-04.
California’s own snow survey and the authority for California snowpack. Its data cannot be read from a browser on this site because it sends no cross origin header on any endpoint tested, including the preflight. It is linked rather than reproduced, and the California page explains where the two networks disagree.
Snow water equivalent measurements on this page are federal records collected by the USDA Natural Resources Conservation Service and are in the public domain. Percentages use the 1991 to 2020 normals period. The California and basin totals are our arithmetic on those measurements and are not agency published indices. Water supply forecasts and runoff projections come from the agencies named above. Every state with a snowpack page →
Hero image: “Boats on Lake Oroville during the 2021 drought” by Frank Schulenburg, CC BY-SA 4.0