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Weather Forecast Office San Francisco Bay Area, CA

California Nevada River Forecast Center

Hydrograph

River at a Glance

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Printable Image About this graph Tabular Data (UTC) Tabular Data (PDT) Datum: Not Available Metadata

NOTE: Graphical forecasts are not available for the Willow Brook at Old Redwood Highway Bridge. During times of high water, forecast crest information can be found in the text products.

Default Hydrograph Scale to Flood Categories   Return to Area Map

Flood Categories (in feet) Major Flood Stage: 44.3 Moderate Flood Stage: 43 Flood Stage: 40.7 Action Stage: 40.7 Low Stage (in feet): -9999 Historic Crests Currently none available. Recent Crests Currently none available. Low Water Records Currently none available.

Zoom Level:14 Legend FEMA Layer Gauge Location 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

If you notice any errors in the below information, please contact our Webmaster
44.3	Major Flood Stage. Water level has reached by bottom of the bridge soffit.
43.9	Flood waters flowing down Redwood Way at Old Redwood Highway.
43.2	Water levels are above bankfull and begin flowing through upstream businesses, including passing through the old lumber company's parking lot.
43	Moderate Flood Stage. A local detention basin may begin to release water onto North McDowell Blvd. Ext.
42.3	Water begins to flow across Ely Road at the railroad track near Old Redwood Highway. Holm Road begins to flood and water ponds on North McDowell at the Post Office.
41.7	City of Petaluma will notify the City Manager and evaluate the need to activate the Emergency Operations Center.
40.7	Action Stage. NWS and City of Petaluma will be closely monitoring the situation. NWS will issue an urban/small stream advisory if not already issued.

About This Location

Latitude: 38.279722° N, Longitude: 122.669444° W, Horizontal Datum: NAD83/WGS84 River Stage Reference Frame Gauge Height Flood Stage Uses NWS stage 0 ft 40.7 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 Not Available Not Available Older USGS topographic maps, NGVD29 benchmarks MSL Not Available Not Available Older USGS topographic maps, MSL benchmarks Other Not Available Not Available

Resources

Hydrologic Resources Text Products Past Precipitation Forecast Precipitation River Forecast Centers River Stage Summary California Data Exchange Center Most Recent Scheduled Reservoir Releases USGS Real-time Data for California USGS - Western Region Geologic Information Inundation Mapping Locations

Additional Resources Area Hydrographs NWS Precipitation and River Forecasting AHPS Iframes for Developers Mobile iNWS for emergency management Snow Information

Collaborative Agencies 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 San Francisco Bay Area Weather Forecast Office 21 Grace Hopper Ave, Stop 5 Monterey, CA 93943-5505 (831) 656-1725 Ask Questions/Webmaster Page last modified: 2-Nov-2020 7:27 PM Disclaimer Credits Glossary Privacy Policy About Us Career Opportunities