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Weather Forecast Office (Baltimore/Washington) Sterling, VA

Middle Atlantic River Forecast Center

Hydrograph

River at a Glance

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About this graph Tabular Data (UTC) Tabular Data (EDT) Datum: NAVD88 Metadata

NOTE: Gauge awaiting repair - automated readings are not available at this time. NOTE: Forecasts for the Potomac River at Dam Number Five above Williamsport are issued routinely year-round.

Default Hydrograph Scale to Flood Categories   Return to Area Map

Upstream Gauge

Downstream Gauge

Flood Categories (in feet) Major Flood Stage: 27 Moderate Flood Stage: 24 Flood Stage: 21 Action Stage: 14 Low Stage (in feet): -9999 Historic Crests (1) 21.32 ft on 05/08/2022 (P) (P): Preliminary values subject to further review. Recent Crests (1) 21.32 ft on 05/08/2022 (P) (P): Preliminary values subject to further review. Low Water Records Currently none available. For more information on your flood risk go to www.floodsmart.gov. Show FEMA's National Flood Hazard Layers FEMA's National Flood Hazard Layers not showing? Why aren't the FEMA National Flood Hazard Layers showing on the ESRI Map? Possible reasons: There are no FEMA National Flood Hazard Layers for the location which you are viewing on ESRI Maps. The FEMA Web Mapping Service (WMS) is down. Note: Your zoom level may have changed. ESRI's zoom levels must be between 14 and 16 to show National Flood Hazard layers.

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
31	Floodwaters enter the Williamsport Cushwa Visitor Center.
29	The vast majority of the C&O Canal towpath is under water.
27	Widespread flooding is ongoing at River Bend and Potomac Fish & Game Club. Three feet of water are inside the first floor of the powerhouse at Dam Number Five. Water is approaching outbuildings at the Cushwa Basin with the parking lot flooded.
25	Structures are flooded at both Potomac Fish & Game Club and River Bend.
24	Water reaches the first floor of the powerhouse at Dam Number Five, with relatively widespread flooding ongoing at River Bend.
23	Lower portions of the Potomac Fish & Game Club property begin to flood.
22	Water reaches the gate of the boat ramp at River Bend and starts to come overbank in a larger area. Backwater from the Potomac comes up the Conococheague, causing flooding of the parking area at Cushwa Basin. Significant portions of the C&O Canal Towpath are flooded, including the Four Locks area parking lot.
21	Water reaches non-permanent structures in the River Bend RV Community, including RVs and outbuildings.
20	The private drive leading to Dam Number Five on the West Virginia side of the river begins to flood. The entire Four Locks parking lot for the C&O Canal is flooded, along with portions of the towpath and low-lying land within the River Bend RV Community.
18	Water begins to come over the bank in low-lying portions of the River Bend RV Community. Property owners should consider moving items that are close to the river. Portions of the C&O Canal Towpath and Four Locks area parking lot are flooded.
14	Portions of the C&O Canal Towpath start to flood west of Williamsport, and the Four Locks parking lot along the C&O Canal also begins to flood.

About This Location

Latitude: 39.605173° N, Longitude: 77.922952° W, Horizontal Datum: NAD83/WGS84 River Stage Reference Frame Gauge Height Flood Stage Uses NWS stage 0 ft 21 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 340.40 361.40 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

Additional Information

Forecast and warning services began at this site on December 11, 2019.

Resources

Hydrologic Resources Text Products Past Precipitation Forecast Precipitation River Forecast Centers River Stage Summary Automated Flood Warning Systems Inundation Mapping Locations

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

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 (Baltimore/Washington) Sterling Weather Forecast Office 43858 Weather Service Rd. Sterling, VA 20166 (571) 888-3500 Ask Questions/Webmaster Page last modified: 2-Nov-2020 7:30 PM Disclaimer Credits Glossary Privacy Policy About Us Career Opportunities