San Joaquin River at Vernalis
Critical Stages
24.5' - Action
29' - Flood
32' - Moderate
37.3' - Major
Latest Observation
Updated: 12:45 AM PST 12/18/25
Status: No Flooding
Stage: 8.09 ft
Flow: 1.07 kcfs
Forecast
| Time | Stage (ft) | Flow (kcfs) |
|---|---|---|
| 2 AM 12/18 | 8.14 | 1.1 |
| 3 AM 12/18 | 8.15 | 1.11 |
| 4 AM 12/18 | 8.16 | 1.11 |
| 5 AM 12/18 | 8.18 | 1.12 |
| 6 AM 12/18 | 8.2 | 1.14 |
| 7 AM 12/18 | 8.21 | 1.14 |
| 8 AM 12/18 | 8.23 | 1.15 |
| 9 AM 12/18 | 8.25 | 1.16 |
| 10 AM 12/18 | 8.27 | 1.18 |
| 11 AM 12/18 | 8.29 | 1.19 |
| 12 PM 12/18 | 8.3 | 1.19 |
| 1 PM 12/18 | 8.32 | 1.2 |
| 2 PM 12/18 | 8.34 | 1.22 |
| 3 PM 12/18 | 8.36 | 1.23 |
| 4 PM 12/18 | 8.37 | 1.24 |
| 5 PM 12/18 | 8.39 | 1.25 |
| 6 PM 12/18 | 8.4 | 1.25 |
| 7 PM 12/18 | 8.42 | 1.27 |
| 8 PM 12/18 | 8.43 | 1.27 |
| 9 PM 12/18 | 8.45 | 1.28 |
| 10 PM 12/18 | 8.46 | 1.29 |
| 11 PM 12/18 | 8.47 | 1.29 |
| 12 AM 12/19 | 8.48 | 1.3 |
| 1 AM 12/19 | 8.5 | 1.31 |
| 2 AM 12/19 | 8.51 | 1.32 |
| 3 AM 12/19 | 8.52 | 1.32 |
| 4 AM 12/19 | 8.53 | 1.33 |
| 5 AM 12/19 | 8.54 | 1.34 |
| 6 AM 12/19 | 8.55 | 1.34 |
| 7 AM 12/19 | 8.56 | 1.35 |
| 8 AM 12/19 | 8.56 | 1.35 |
| 9 AM 12/19 | 8.57 | 1.36 |
| 10 AM 12/19 | 8.58 | 1.36 |
| 11 AM 12/19 | 8.59 | 1.37 |
| 12 PM 12/19 | 8.59 | 1.37 |
| 1 PM 12/19 | 8.6 | 1.37 |
| 2 PM 12/19 | 8.61 | 1.38 |
| 3 PM 12/19 | 8.61 | 1.38 |
| 4 PM 12/19 | 8.62 | 1.39 |
| 5 PM 12/19 | 8.62 | 1.39 |
| 6 PM 12/19 | 8.63 | 1.39 |
| 7 PM 12/19 | 8.63 | 1.39 |
| 8 PM 12/19 | 8.64 | 1.4 |
| 9 PM 12/19 | 8.64 | 1.4 |
| 10 PM 12/19 | 8.64 | 1.4 |
| 11 PM 12/19 | 8.65 | 1.41 |
| 12 AM 12/20 | 8.65 | 1.41 |
| 1 AM 12/20 | 8.65 | 1.41 |
| 2 AM 12/20 | 8.66 | 1.41 |
| 3 AM 12/20 | 8.66 | 1.41 |
| 4 AM 12/20 | 8.66 | 1.41 |
| 5 AM 12/20 | 8.67 | 1.42 |
| 6 AM 12/20 | 8.67 | 1.42 |
| 7 AM 12/20 | 8.67 | 1.42 |
| 8 AM 12/20 | 8.67 | 1.42 |
| 9 AM 12/20 | 8.67 | 1.42 |
| 10 AM 12/20 | 8.68 | 1.43 |
| 11 AM 12/20 | 8.68 | 1.43 |
| 12 PM 12/20 | 8.68 | 1.43 |
| 1 PM 12/20 | 8.68 | 1.43 |
| 2 PM 12/20 | 8.68 | 1.43 |
| 3 PM 12/20 | 8.68 | 1.43 |
| 4 PM 12/20 | 8.69 | 1.43 |
| 5 PM 12/20 | 8.69 | 1.43 |
| 6 PM 12/20 | 8.69 | 1.43 |
| 7 PM 12/20 | 8.69 | 1.43 |
| 8 PM 12/20 | 8.69 | 1.43 |
| 9 PM 12/20 | 8.69 | 1.43 |
| 10 PM 12/20 | 8.69 | 1.43 |
| 11 PM 12/20 | 8.69 | 1.43 |
| 12 AM 12/21 | 8.69 | 1.43 |
| 1 AM 12/21 | 8.69 | 1.43 |
| 2 AM 12/21 | 8.69 | 1.43 |
| 3 AM 12/21 | 8.69 | 1.43 |
| 4 AM 12/21 | 8.69 | 1.43 |
| 5 AM 12/21 | 8.7 | 1.44 |
| 6 AM 12/21 | 8.7 | 1.44 |
| 7 AM 12/21 | 8.7 | 1.44 |
| 8 AM 12/21 | 8.7 | 1.44 |
| 9 AM 12/21 | 8.7 | 1.44 |
| 10 AM 12/21 | 8.7 | 1.44 |
| 11 AM 12/21 | 8.7 | 1.44 |
| 12 PM 12/21 | 8.7 | 1.44 |
| 1 PM 12/21 | 8.7 | 1.44 |
| 2 PM 12/21 | 8.7 | 1.44 |
| 3 PM 12/21 | 8.71 | 1.44 |
| 4 PM 12/21 | 8.71 | 1.44 |
| 5 PM 12/21 | 8.71 | 1.44 |
| 6 PM 12/21 | 8.71 | 1.44 |
| 7 PM 12/21 | 8.71 | 1.44 |
| 8 PM 12/21 | 8.71 | 1.44 |
| 9 PM 12/21 | 8.71 | 1.44 |
| 10 PM 12/21 | 8.71 | 1.44 |
| 11 PM 12/21 | 8.71 | 1.44 |
| 12 AM 12/22 | 8.71 | 1.44 |
| 1 AM 12/22 | 8.71 | 1.44 |
| 2 AM 12/22 | 8.71 | 1.44 |
| 3 AM 12/22 | 8.72 | 1.45 |
| 4 AM 12/22 | 8.72 | 1.45 |
| Time | Stage (ft) | Flow (kcfs) |
|---|---|---|
| 12:45 AM 12/18 | 8.09 | 1.07 |
| 12:30 AM 12/18 | 8.09 | 1.07 |
| 12:15 AM 12/18 | 8.09 | 1.07 |
| 12:00 AM 12/18 | 8.09 | 1.07 |
| 11:45 PM 12/17 | 8.09 | 1.07 |
| 11:30 PM 12/17 | 8.09 | 1.07 |
| 11:15 PM 12/17 | 8.09 | 1.07 |
| 11:00 PM 12/17 | 8.08 | 1.07 |
| 10:45 PM 12/17 | 8.08 | 1.07 |
| 10:30 PM 12/17 | 8.09 | 1.07 |
| 10:15 PM 12/17 | 8.08 | 1.07 |
| 10:00 PM 12/17 | 8.07 | 1.06 |
| 9:45 PM 12/17 | 8.07 | 1.06 |
| 9:30 PM 12/17 | 8.06 | 1.06 |
| 9:15 PM 12/17 | 8.06 | 1.06 |
| 9:00 PM 12/17 | 8.07 | 1.06 |
| 8:45 PM 12/17 | 8.07 | 1.06 |
| 8:30 PM 12/17 | 8.08 | 1.07 |
| 8:15 PM 12/17 | 8.09 | 1.07 |
| 8:00 PM 12/17 | 8.09 | 1.07 |
| 7:45 PM 12/17 | 8.09 | 1.07 |
| 7:30 PM 12/17 | 8.09 | 1.07 |
| 7:15 PM 12/17 | 8.09 | 1.07 |
| 7:00 PM 12/17 | 8.09 | 1.07 |
| 6:45 PM 12/17 | 8.09 | 1.07 |
| 6:30 PM 12/17 | 8.09 | 1.07 |
| 6:15 PM 12/17 | 8.09 | 1.07 |
| 6:00 PM 12/17 | 8.09 | 1.07 |
| 5:45 PM 12/17 | 8.09 | 1.07 |
| 5:30 PM 12/17 | 8.09 | 1.07 |
37.29' -
Stages above 37.3 feet results in flooding outside the levees. Top of levee.
29.6' -
Homes along east bank of river on Airport Court in Manteca experience flooding.
26' -
Severe seepage occurs outside the levees. The area covered by seepage will increase as the river stage rises.
24.5' -
Monitor Stage - water reaches the toe of levee.
21' -
Seepage begins into crop area outside of levees.
| Date | Stage (ft) |
|---|---|
| Jan 5, 1997 | 34.88 |
| Jan 27, 1969 | 34.55 |
| Dec 9, 1950 | 32.81 |
| Mar 16, 1938 | 32.71 |
| Feb 12, 1938 | 32.11 |
| Feb 23, 2017 | 30.72 |
| Apr 2, 1940 | 30.43 |
| Mar 19, 2023 | 29.83 |
| Mar 18, 1986 | 29.8 |
| Apr 13, 2006 | 29.25 |
| Apr 18, 1982 | 29.12 |
| Jan 6, 1984 | 29 |
| Feb 13, 1998 | 28.66 |
| Apr 2, 2011 | 27.17 |
| May 4, 1978 | 26.9 |
| Apr 30, 1967 | 26.8 |
| Mar 20, 1995 | 26.77 |
| Jan 18, 2023 | 25.7 |
| Jan 12, 1965 | 25.5 |
| Mar 4, 2019 | 21.84 |
Data provided by the National Weather Service.
