Page developed via a collaboration between CW3E and CNAP by David Pierce, CW3E Director Marty Ralph, and CNAP PI Dan Cayan.
This page shows the accumulated water year-to-date precipitation for various locations in California and Nevada. Currently included locations are: San Diego county; the state of California; the Northern Sierra eight-station index; the Las Vegas region (Clark County, Nevada); and the Reno/Carson City/Lake Tahoe area straddling the California-Nevada border. Water years start on October 1st and extend through the following September 30th and are numbered by the year of the January of the water year. For example, the period October 1, 2015 to September 30, 2016 is water year "2016", since the January in that period is January 2016.
Values are shown as a percent of normal (mean) accumulation found on the last day of the water year. So, values always start at zero on October 1st and increase gradually over the year (never declining). For example, if the "Current" value is 15% and the "1-day delta" (change) is 1.0%, that means that currently we have accumulated 15% of the total precipitation we usually accumulate over an entire water year, and that yesterday that number was 14%. For a normal year, the "Current" value will end up at 100% at the end of the water year. A dry year will end up below 100%, and a wet year will end above 100%.
Note: Percentile values for the 1-, 2-, and 3-day changes are in percentage points of the mean accumulation in a water year, and are calculated excluding any values of zero (i.e., dry periods are not counted).
Data updated 2023/01/25 23:54 Pacific time
San Diego County (station list) (archive of past tables)
| Current: | 96.7% | 1‑day Δ: | 0.00% | 2‑day Δ: | 0.00% | 3‑day Δ: | 0.00% |
| -------- | -------- | -------- | -------- | -------- | -------- | -------- | -------- |
| (1963/01/25) | |||||||
| Rec_low: | 4.6% | 50‑ptile: | 0.63% | 50‑ptile: | 1.04% | 50‑ptile: | 1.38% |
| Typ_low: | 19.3% | 90‑ptile: | 4.35% | 90‑ptile: | 6.62% | 90‑ptile: | 8.46% |
| Mean: | 42.5% | 95‑ptile: | 6.30% | 95‑ptile: | 9.69% | 95‑ptile: | 11.91% |
| Typ_high: | 63.6% | 99‑ptile: | 10.69% | 99‑ptile: | 17.30% | 99‑ptile: | 21.44% |
| Rec_high: | 127.0% | Record: | 31.91% | Record: | 45.37% | Record: | 58.63% |
| (1993/01/25) | (1927/02/16) | (1927/02/17) | (1927/02/17) |
Greater Los Angeles Region (station list) (archive of past tables)
| Current: | 84.2% | 1‑day Δ: | 0.00% | 2‑day Δ: | 0.00% | 3‑day Δ: | 0.00% |
| -------- | -------- | -------- | -------- | -------- | -------- | -------- | -------- |
| (1963/01/25) | |||||||
| Rec_low: | 1.7% | 50‑ptile: | 0.36% | 50‑ptile: | 0.59% | 50‑ptile: | 0.86% |
| Typ_low: | 19.1% | 90‑ptile: | 4.92% | 90‑ptile: | 7.77% | 90‑ptile: | 9.69% |
| Mean: | 46.9% | 95‑ptile: | 7.33% | 95‑ptile: | 11.51% | 95‑ptile: | 14.64% |
| Typ_high: | 70.8% | 99‑ptile: | 13.08% | 99‑ptile: | 20.39% | 99‑ptile: | 26.88% |
| Rec_high: | 131.8% | Record: | 25.28% | Record: | 45.44% | Record: | 52.14% |
| (2005/01/25) | (1938/03/02) | (1943/01/23) | (1943/01/24) |
All California (station list) (archive of past tables)
| Current: | 72.3% | 1‑day Δ: | 0.04% | 2‑day Δ: | 0.10% | 3‑day Δ: | 0.10% |
| -------- | -------- | -------- | -------- | -------- | -------- | -------- | -------- |
| (2014/01/25) | |||||||
| Rec_low: | 7.2% | 50‑ptile: | 0.22% | 50‑ptile: | 0.48% | 50‑ptile: | 0.76% |
| Typ_low: | 29.4% | 90‑ptile: | 2.27% | 90‑ptile: | 3.96% | 90‑ptile: | 5.47% |
| Mean: | 50.3% | 95‑ptile: | 3.18% | 95‑ptile: | 5.47% | 95‑ptile: | 7.47% |
| Typ_high: | 72.3% | 99‑ptile: | 4.88% | 99‑ptile: | 8.69% | 99‑ptile: | 11.71% |
| Rec_high: | 97.5% | Record: | 9.05% | Record: | 15.67% | Record: | 21.00% |
| (2017/01/25) | (1943/01/21) | (1955/12/23) | (1943/01/23) |
Northern Sierra Nevada 8-Station Index (station list; a traditional indicator of CA water supply) (archive of past tables)
| Current: | 77.3% | 1‑day Δ: | 0.01% | 2‑day Δ: | 0.03% | 3‑day Δ: | 0.03% |
| -------- | -------- | -------- | -------- | -------- | -------- | -------- | -------- |
| (2014/01/25) | |||||||
| Rec_low: | 7.4% | 50‑ptile: | 0.35% | 50‑ptile: | 0.66% | 50‑ptile: | 0.99% |
| Typ_low: | 29.4% | 90‑ptile: | 2.57% | 90‑ptile: | 4.31% | 90‑ptile: | 5.91% |
| Mean: | 51.9% | 95‑ptile: | 3.55% | 95‑ptile: | 6.09% | 95‑ptile: | 8.20% |