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Hydrograph River at a Glance Download
San Joaquin River at Vernalis Stage (ft)Flow (kcfs)Observed: 8.01 ft at 8:00AM May 09, 2021Observed: 8.01 ft at 8:15AM May 09, 2021Observed: 8 ft at 8:30AM May 09, 2021Observed: 8.01 ft at 8:45AM May 09, 2021Observed: 8.01 ft at 9:00AM May 09, 2021Observed: 8 ft at 9:15AM May 09, 2021Observed: 8.01 ft at 9:30AM May 09, 2021Observed: 8.01 ft at 9:45AM May 09, 2021Observed: 8 ft at 10:00AM May 09, 2021Observed: 8.01 ft at 10:15AM May 09, 2021Observed: 8.01 ft at 10:30AM May 09, 2021Observed: 8.01 ft at 10:45AM May 09, 2021Observed: 8 ft at 11:00AM May 09, 2021Observed: 8.01 ft at 11:15AM May 09, 2021Observed: 8.02 ft at 11:30AM May 09, 2021Observed: 8.02 ft at 11:45AM May 09, 2021Observed: 8.01 ft at 12:00PM May 09, 2021Observed: 8.02 ft at 12:15PM May 09, 2021Observed: 8.03 ft at 12:30PM May 09, 2021Observed: 8.03 ft at 12:45PM May 09, 2021Observed: 8.03 ft at 1:00PM May 09, 2021Observed: 8.04 ft at 1:15PM May 09, 2021Observed: 8.04 ft at 1:30PM May 09, 2021Observed: 8.04 ft at 1:45PM May 09, 2021Observed: 8.04 ft at 2:00PM May 09, 2021Observed: 8.05 ft at 2:15PM May 09, 2021Observed: 8.06 ft at 2:30PM May 09, 2021Observed: 8.06 ft at 2:45PM May 09, 2021Observed: 8.06 ft at 3:00PM May 09, 2021Observed: 8.05 ft at 3:15PM May 09, 2021Observed: 8.06 ft at 3:30PM May 09, 2021Observed: 8.06 ft at 3:45PM May 09, 2021Observed: 8.06 ft at 4:00PM May 09, 2021Observed: 8.07 ft at 4:15PM May 09, 2021Observed: 8.07 ft at 4:30PM May 09, 2021Observed: 8.07 ft at 4:45PM May 09, 2021Observed: 8.08 ft at 5:00PM May 09, 2021Observed: 8.08 ft at 5:15PM May 09, 2021Observed: 8.08 ft at 5:30PM May 09, 2021Observed: 8.08 ft at 5:45PM May 09, 2021Observed: 8.08 ft at 6:00PM May 09, 2021Observed: 8.08 ft at 6:15PM May 09, 2021Observed: 8.08 ft at 6:30PM May 09, 2021Observed: 8.08 ft at 6:45PM May 09, 2021Observed: 8.08 ft at 7:00PM May 09, 2021Observed: 8.09 ft at 7:15PM May 09, 2021Observed: 8.09 ft at 7:30PM May 09, 2021Observed: 8.09 ft at 7:45PM May 09, 2021Observed: 8.09 ft at 8:00PM May 09, 2021Observed: 8.09 ft at 8:15PM May 09, 2021Observed: 8.09 ft at 8:30PM May 09, 2021Observed: 8.09 ft at 8:45PM May 09, 2021Observed: 8.09 ft at 9:00PM May 09, 2021Observed: 8.09 ft at 9:15PM May 09, 2021Observed: 8.09 ft at 9:30PM May 09, 2021Observed: 8.09 ft at 9:45PM May 09, 2021Observed: 8.09 ft at 10:00PM May 09, 2021Observed: 8.09 ft at 10:15PM May 09, 2021Observed: 8.1 ft at 10:30PM May 09, 2021Observed: 8.09 ft at 10:45PM May 09, 2021Observed: 8.1 ft at 11:00PM May 09, 2021Observed: 8.09 ft at 11:15PM May 09, 2021Observed: 8.1 ft at 11:30PM May 09, 2021Observed: 8.1 ft at 11:45PM May 09, 2021Observed: 8.1 ft at 12:00AM May 10, 2021Observed: 8.1 ft at 12:15AM May 10, 2021Observed: 8.1 ft at 12:30AM May 10, 2021Observed: 8.11 ft at 12:45AM May 10, 2021Observed: 8.11 ft at 1:00AM May 10, 2021Observed: 8.11 ft at 1:15AM May 10, 2021Observed: 8.11 ft at 1:30AM May 10, 2021Observed: 8.11 ft at 1:45AM May 10, 2021Observed: 8.12 ft at 2:00AM May 10, 2021Observed: 8.11 ft at 2:15AM May 10, 2021Observed: 8.12 ft at 2:30AM May 10, 2021Observed: 8.12 ft at 2:45AM May 10, 2021Observed: 8.12 ft at 3:00AM May 10, 2021Observed: 8.12 ft at 3:15AM May 10, 2021Observed: 8.12 ft at 3:30AM May 10, 2021Observed: 8.12 ft at 3:45AM May 10, 2021Observed: 8.12 ft at 4:00AM May 10, 2021Observed: 8.13 ft at 4:15AM May 10, 2021Observed: 8.13 ft at 4:30AM May 10, 2021Observed: 8.13 ft at 4:45AM May 10, 2021Observed: 8.13 ft at 5:00AM May 10, 2021Observed: 8.13 ft at 5:15AM May 10, 2021Observed: 8.13 ft at 5:30AM May 10, 2021Observed: 8.14 ft at 5:45AM May 10, 2021Observed: 8.14 ft at 6:00AM May 10, 2021Observed: 8.14 ft at 6:15AM May 10, 2021Observed: 8.15 ft at 6:30AM May 10, 2021Observed: 8.15 ft at 6:45AM May 10, 2021Observed: 8.15 ft at 7:00AM May 10, 2021Observed: 8.15 ft at 7:15AM May 10, 2021Observed: 8.16 ft at 7:30AM May 10, 2021Observed: 8.16 ft at 7:45AM May 10, 2021Observed: 8.15 ft at 8:00AM May 10, 2021Observed: 8.15 ft at 8:15AM May 10, 2021Observed: 8.15 ft at 8:30AM May 10, 2021Observed: 8.15 ft at 8:45AM May 10, 2021Observed: 8.14 ft at 9:00AM May 10, 2021Observed: 8.14 ft at 9:15AM May 10, 2021Observed: 8.13 ft at 9:30AM May 10, 2021Observed: 8.13 ft at 9:45AM May 10, 2021Observed: 8.13 ft at 10:00AM May 10, 2021Observed: 8.12 ft at 10:15AM May 10, 2021Observed: 8.12 ft at 10:30AM May 10, 2021Observed: 8.11 ft at 10:45AM May 10, 2021Observed: 8.11 ft at 11:00AM May 10, 2021Observed: 8.1 ft at 11:15AM May 10, 2021Observed: 8.09 ft at 11:30AM May 10, 2021Observed: 8.09 ft at 11:45AM May 10, 2021Observed: 8.09 ft at 12:00PM May 10, 2021Observed: 8.08 ft at 12:15PM May 10, 2021Observed: 8.07 ft at 12:30PM May 10, 2021Observed: 8.08 ft at 12:45PM May 10, 2021Observed: 8.06 ft at 1:00PM May 10, 2021Observed: 8.07 ft at 1:15PM May 10, 2021Observed: 8.06 ft at 1:30PM May 10, 2021Observed: 8.05 ft at 1:45PM May 10, 2021Observed: 8.05 ft at 2:00PM May 10, 2021Observed: 8.05 ft at 2:15PM May 10, 2021Observed: 8.04 ft at 2:30PM May 10, 2021Observed: 8.03 ft at 2:45PM May 10, 2021Observed: 8.03 ft at 3:00PM May 10, 2021Observed: 8.03 ft at 3:15PM May 10, 2021Observed: 8.03 ft at 3:30PM May 10, 2021Observed: 8.03 ft at 3:45PM May 10, 2021Observed: 8.02 ft at 4:00PM May 10, 2021Observed: 8.01 ft at 4:15PM May 10, 2021Observed: 8.01 ft at 4:30PM May 10, 2021Observed: 8 ft at 4:45PM May 10, 2021Observed: 8.01 ft at 5:00PM May 10, 2021Observed: 8 ft at 5:15PM May 10, 2021Observed: 8 ft at 5:30PM May 10, 2021Observed: 8 ft at 5:45PM May 10, 2021Observed: 7.99 ft at 6:00PM May 10, 2021Observed: 7.99 ft at 6:15PM May 10, 2021Observed: 7.99 ft at 6:30PM May 10, 2021Observed: 7.99 ft at 6:45PM May 10, 2021Observed: 7.99 ft at 7:00PM May 10, 2021Observed: 8 ft at 7:15PM May 10, 2021Observed: 8 ft at 7:30PM May 10, 2021Observed: 8 ft at 7:45PM May 10, 2021Observed: 8 ft at 8:00PM May 10, 2021Observed: 8 ft at 8:15PM May 10, 2021Observed: 8 ft at 8:30PM May 10, 2021Observed: 8 ft at 8:45PM May 10, 2021Observed: 8.01 ft at 9:00PM May 10, 2021Observed: 8 ft at 9:15PM May 10, 2021Observed: 8.01 ft at 9:30PM May 10, 2021Observed: 8 ft at 9:45PM May 10, 2021Observed: 8.01 ft at 10:00PM May 10, 2021Observed: 8 ft at 10:15PM May 10, 2021Observed: 8 ft at 10:30PM May 10, 2021Observed: 8.01 ft at 10:45PM May 10, 2021Observed: 8 ft at 11:00PM May 10, 2021Observed: 8.01 ft at 11:15PM May 10, 2021Observed: 8 ft at 11:30PM May 10, 2021Observed: 8 ft at 11:45PM May 10, 2021Observed: 8 ft at 12:00AM May 11, 2021Observed: 8 ft at 12:15AM May 11, 2021Observed: 8 ft at 12:30AM May 11, 2021Observed: 8 ft at 12:45AM May 11, 2021Observed: 8.01 ft at 1:00AM May 11, 2021Observed: 8 ft at 1:15AM May 11, 2021Observed: 8 ft at 1:30AM May 11, 2021Observed: 8 ft at 1:45AM May 11, 2021Observed: 8 ft at 2:00AM May 11, 2021Observed: 8 ft at 2:15AM May 11, 2021Observed: 8 ft at 2:30AM May 11, 2021Observed: 8 ft at 2:45AM May 11, 2021Observed: 8 ft at 3:00AM May 11, 2021Observed: 8 ft at 3:15AM May 11, 2021Observed: 8 ft at 3:30AM May 11, 2021Observed: 8 ft at 3:45AM May 11, 2021Observed: 8 ft at 4:00AM May 11, 2021Observed: 8 ft at 4:15AM May 11, 2021Observed: 8 ft at 4:30AM May 11, 2021Observed: 8 ft at 4:45AM May 11, 2021Observed: 8 ft at 5:00AM May 11, 2021Observed: 8 ft at 5:15AM May 11, 2021Observed: 8 ft at 5:30AM May 11, 2021Observed: 7.99 ft at 5:45AM May 11, 2021Observed: 8 ft at 6:00AM May 11, 2021Observed: 7.99 ft at 6:15AM May 11, 2021Observed: 7.99 ft at 6:30AM May 11, 2021Observed: 7.99 ft at 6:45AM May 11, 2021Observed: 8 ft at 7:00AM May 11, 2021Observed: 8 ft at 7:15AM May 11, 2021Observed: 8 ft at 7:30AM May 11, 2021Observed: 8 ft at 7:45AM May 11, 2021Observed: 8 ft at 8:00AM May 11, 2021Observed: 7.99 ft at 8:15AM May 11, 2021Observed: 7.99 ft at 8:30AM May 11, 2021Observed: 7.99 ft at 8:45AM May 11, 2021Observed: 7.99 ft at 9:00AM May 11, 2021Observed: 7.99 ft at 9:15AM May 11, 2021Observed: 7.98 ft at 9:30AM May 11, 2021Observed: 7.98 ft at 9:45AM May 11, 2021Observed: 7.98 ft at 10:00AM May 11, 2021Observed: 7.98 ft at 10:15AM May 11, 2021Observed: 7.97 ft at 10:30AM May 11, 2021Observed: 7.97 ft at 10:45AM May 11, 2021Observed: 7.97 ft at 11:00AM May 11, 2021Observed: 7.96 ft at 11:15AM May 11, 2021Observed: 7.97 ft at 11:30AM May 11, 2021Observed: 7.96 ft at 11:45AM May 11, 2021Observed: 7.96 ft at 12:00PM May 11, 2021Observed: 7.96 ft at 12:15PM May 11, 2021Observed: 7.96 ft at 12:30PM May 11, 2021Observed: 7.95 ft at 12:45PM May 11, 2021Observed: 7.95 ft at 1:00PM May 11, 2021Observed: 7.95 ft at 1:15PM May 11, 2021Observed: 7.95 ft at 1:30PM May 11, 2021Observed: 7.95 ft at 1:45PM May 11, 2021Observed: 7.95 ft at 2:00PM May 11, 2021Observed: 7.95 ft at 2:15PM May 11, 2021Observed: 7.95 ft at 2:30PM May 11, 2021Observed: 7.95 ft at 2:45PM May 11, 2021Observed: 7.95 ft at 3:00PM May 11, 2021Observed: 7.95 ft at 3:15PM May 11, 2021Observed: 7.95 ft at 3:30PM May 11, 2021Observed: 7.95 ft at 3:45PM May 11, 2021Observed: 7.95 ft at 4:00PM May 11, 2021Observed: 7.95 ft at 4:15PM May 11, 2021Observed: 7.96 ft at 4:30PM May 11, 2021Observed: 7.96 ft at 4:45PM May 11, 2021Observed: 7.96 ft at 5:00PM May 11, 2021Observed: 7.96 ft at 5:15PM May 11, 2021Observed: 7.97 ft at 5:30PM May 11, 2021Observed: 7.97 ft at 5:45PM May 11, 2021Observed: 7.98 ft at 6:00PM May 11, 2021Observed: 7.98 ft at 6:15PM May 11, 2021Observed: 7.98 ft at 6:30PM May 11, 2021Observed: 7.99 ft at 6:45PM May 11, 2021Observed: 7.99 ft at 7:00PM May 11, 2021Observed: 8 ft at 7:15PM May 11, 2021Observed: 8 ft at 7:30PM May 11, 2021Observed: 8 ft at 7:45PM May 11, 2021Observed: 8.01 ft at 8:00PM May 11, 2021Observed: 8.01 ft at 8:15PM May 11, 2021Observed: 8.02 ft at 8:30PM May 11, 2021Observed: 8.02 ft at 8:45PM May 11, 2021Observed: 8.03 ft at 9:00PM May 11, 2021Observed: 8.03 ft at 9:15PM May 11, 2021Observed: 8.04 ft at 9:30PM May 11, 2021Observed: 8.05 ft at 9:45PM May 11, 2021Observed: 8.05 ft at 10:00PM May 11, 2021Observed: 8.05 ft at 10:15PM May 11, 2021Observed: 8.06 ft at 10:30PM May 11, 2021Observed: 8.07 ft at 10:45PM May 11, 2021Observed: 8.07 ft at 11:00PM May 11, 2021Observed: 8.08 ft at 11:15PM May 11, 2021Observed: 8.08 ft at 11:30PM May 11, 2021Observed: 8.09 ft at 11:45PM May 11, 2021Observed: 8.1 ft at 12:00AM May 12, 2021Observed: 8.1 ft at 12:15AM May 12, 2021Observed: 8.1 ft at 12:30AM May 12, 2021Observed: 8.11 ft at 12:45AM May 12, 2021Observed: 8.11 ft at 1:00AM May 12, 2021Observed: 8.12 ft at 1:15AM May 12, 2021Observed: 8.13 ft at 1:30AM May 12, 2021Observed: 8.13 ft at 1:45AM May 12, 2021Observed: 8.13 ft at 2:00AM May 12, 2021Observed: 8.14 ft at 2:15AM May 12, 2021Observed: 8.14 ft at 2:30AM May 12, 2021Observed: 8.15 ft at 2:45AM May 12, 2021Observed: 8.16 ft at 3:00AM May 12, 2021Observed: 8.17 ft at 3:15AM May 12, 2021Observed: 8.17 ft at 3:30AM May 12, 2021Observed: 8.17 ft at 3:45AM May 12, 2021Observed: 8.18 ft at 4:00AM May 12, 2021Observed: 8.18 ft at 4:15AM May 12, 2021Observed: 8.19 ft at 4:30AM May 12, 2021Observed: 8.19 ft at 4:45AM May 12, 2021Observed: 8.2 ft at 5:00AM May 12, 2021Observed: 8.2 ft at 5:15AM May 12, 2021Observed: 8.21 ft at 5:30AM May 12, 2021Observed: 8.21 ft at 5:45AM May 12, 2021Observed: 8.22 ft at 6:00AM May 12, 2021Observed: 8.22 ft at 6:15AM May 12, 2021Observed: 8.22 ft at 6:30AM May 12, 2021Highest Observation: 8.23 ft at 6:45AM May 12, 2021USGS--Water Resources of the United StatesVNSC1(plotting HGIRG) Graph Created (7:52AM May 12, 2021)ObservedLatest observed value: 8.23 ft at 6:45 AM PDT 12-May-2021. Flood Stage is 29 ft
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About this graph
Tabular Data (UTC)
Tabular Data (PDT)
XML Data
RSS Files
Datum: NGVD29
Metadata
NOTE: Forecasts for the San Joaquin River at Vernalis are issued routinely year-round.
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Upstream Gauge - at Patterson Upstream Gauge Downstream Gauge Downstream Gauge - at Mossdale Bridge
Flood Categories (in feet)
Major Flood Stage: 37.3
Moderate Flood Stage: 32
Flood Stage: 29
Action Stage: 24.5
Low Stage (in feet): 0

Historic Crests
(1) 34.88 ft on 01/05/1997
(2) 34.55 ft on 01/27/1969
(3) 32.81 ft on 12/09/1950
(4) 32.71 ft on 03/16/1938
(5) 32.11 ft on 02/12/1938
Show More Historic Crests

(P): Preliminary values subject to further review.

Recent Crests
(1) 21.69 ft on 03/04/2019
(2) 17.83 ft on 04/08/2018
(3) 30.72 ft on 02/23/2017
(4) 14.21 ft on 03/15/2016
(5) 9.66 ft on 04/26/2015
Show More Recent Crests

(P): Preliminary values subject to further review.

Low Water Records
Currently none available.
Zoom Level:16
KML Image
Gauge LocationGauge Map Marker
 Disclaimer
Latitude/Longitude Disclaimer: The gauge location shown in the above map is the approximate location based on the latitude/longitude coordinates provided to the NWS by the gauge owner.
Flood Impacts & Photos Collapse
If you notice any errors in the below information, please contact our Webmaster
37.29 Stages above 37.3 feet results in flooding outside the levees. Top of levee.
26 Severe seepage occurs outside the levees. The area covered by seepage will increase as the river stage rises.
21 Seepage begins into crop area outside of levees.
About This Location Collapse

Latitude: 37.676041° N, Longitude: 121.266329° W, Horizontal Datum: NAD83/WGS84

River Stage
Reference Frame		 Gauge Height Flood Stage Uses
NWS stage 0 ft 29 ft Interpreting hydrographs and NWS watch, warnings, and forecasts, and inundation maps
Vertical Datum Elevation
(gauge height = 0)		 Elevation
(gauge height = flood stage)		 Elevation information source
NAVD88 Not Available Not Available Survey grade GPS equipment, FEMA flood plain maps, newer USGS topographic maps
NGVD 29 25.0 Not Available Older USGS topographic maps, NGVD29 benchmarks
MSL Not Available Not Available Older USGS topographic maps, MSL benchmarks
Other Not Available Not Available  

Current/Historical Observations:
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Hydrologic Resources Additional Resources
Collaborative Agencies Collapse
The National Weather Service prepares its forecasts and other services in collaboration with agencies like the US Geological Survey, US Bureau of Reclamation, US Army Corps of Engineers, Natural Resource Conservation Service, National Park Service, ALERT Users Group, Bureau of Indian Affairs, and many state and local emergency managers across the country. For details, please click here.
NWS Information
National Weather Service
Sacramento Weather Forecast Office

Sacramento, CA
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