National Weather Service California Nevada River Forecast Center Department of Commerce National Oceanic and Atmospheric Administration National Weather Service

*** IMPORTANT ***  Week of June 16 - Website Data Outage - Due to a major computer upgrade the week of June 16, nearly all data on the CNRFC web site will not be updated. We anticipate the down time to be approximately 4 days. The latest deterministic hydrologic forecasts for official forecast points will continue to be available at the National Water Prediction Service during this time.
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SAN JOAQUIN RIVER - MOSSDALE (MOSC1)
Latitude: 37.79º NLongitude: 121.31º WElevation: 32 Feet
Location: San Joaquin County in CaliforniaBulletin Group: San JoaquinRiver Group: San Joaquin
Issuance Time: Jun 20 2025 at 11:22 AM PDTNext Issuance: Jun 21 2025 at 9:00 AM PDT
Action/Monitor: 19.5 FeetMinor Flood: 28.5 FeetModerate Flood: 32.1 FeetMajor Flood: 33.1 Feet

Please Note:
1) Each individual timeseries plotted on the graphical river forecast can be toggled on and off by clicking the legend entry above. If the "Observed (Raw Data)" contains bad data and is toggled off, the plot will scale to the remaining timeseries.

2) At extremely low river flows, the "Observed (Raw Data)" may show readings below the lower end of the available rating table, while the "Observed (Simulated)" will only show values at the bottom of the rating table, creating a potential discrepancy between the two readings.
Observed Data Credit
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Raw streamflow data is provided by the California Department of Water Resources.
View California Department of Water Resources Data for this station location.

Verification - Historical Graphical RVF
Month:  
Day:  
Year:  
Cycle:  
To view other verification locations, use our Historical Graphical River Forecast Interface.
Historical Stage/Flow Data
Water Year
Peak Discharge (cfs)
Stage (feet)
Date
 Most Recent 5 Years
2024
--
11.32
Mar 6, 2024
2023
--
20.52
Mar 24, 2023
2022
-- 7.51 Oct 24, 2021
2021
--
6.74
Jun 27, 2021
2020
--
7.93
Dec 13, 2019
 Historical High Stage/Flow Events (Period of Record - Jan 1920 to Present)* - Ranked by Stage
1951
--
24.40**
Dec 10, 1950
1997
--
23.24**
Jan 9, 1997
2017
-- 21.70 Feb 23, 2017
1969
--
20.31**

Jan 27, 1969

1967 -- 18.10** Jan 24, 1967
2006 -- 17.19** Apr 13, 2006
 * No data was available Sep 2006 to Apr 2007
 ** Datum changed from NGVD29 to NAVD88 on 10/01/2006. The difference is +2.38 ft and must be applied to all data before date to convert to NAVD88
Location Photographs
ESRI™ Locator Map
Flood Impacts
33.1 FeetStages above 33.1 feet result in flooding outside of the levees. Top of levee.
16.39 FeetHistorically Mossdale Trailer Park evacuates.
15.4 FeetMossdale Trailer Park is threatened by the high water. Mossdale Trailer Park is on the south side of the river inside the levee both upstream and downstream of the gage.
Official 7 Day National Weather Service Forecast   (CAZ019)
Today: Sunny, breezy. Highs 74 to 84. Northwest winds 10 to 15 mph increasing to 15 to 25 mph in the afternoon. Gusts up to 35 mph.

Tonight: Clear. Lows 51 to 61. Northwest winds 10 to 20 mph with gusts to around 30 mph.

Sunday: Sunny. Highs 80 to 88. Northwest winds 10 to 15 mph with gusts to around 25 mph.

Sunday Night: Clear. Lows 53 to 59. Northwest winds up to 15 mph.

Monday: Sunny. Highs 85 to 93. Northwest winds up to 10 mph.

Monday Night: Clear. Lows 56 to 62.

Tuesday: Sunny. Highs 87 to 94.

Tuesday Night through Friday: Clear. Lows 54 to 64. Highs 87 to 97.
Product Disclaimer

This river graphic is not intended to serve as a substitute for official flood watches, warnings, advisories, or statements issued by the NWS Sacramento Weather Forecast Office. Observations are preliminary and subject to change. River levels identified as "forecast" should be consistent with those contained in official NWS products. River levels identified as "guidance" have significant uncertainty due to future weather or reservoir regulation and are provided for planning purposes only.