Web Portal Changes: The Advanced Hydrologic Prediction Service (AHPS) hosted at https://water.weather.gov will be replaced by the National Water Prediction Service (NWPS), with a target of March 2024. Existing AHPS content and features will be preserved and expanded within NWPS.

Experimental National Water Center Products: The National Hydrologic Discussion, Area Hydrologic Discussion, and Flood Hazard Outlook, and real-time geospatial services depicting River Forecast Center and National Water Model forecasts, continue to be accessible via https://www.weather.gov/owp/operations, as described in the StoryMap here.

Weather Forecast Office (Baltimore/Washington) Sterling, VA

Middle Atlantic River Forecast Center

Air Quality Alert

Hydrograph

River at a Glance

Download

Probability Information Weekly Chance of Exceeding Levels Chance of Exceeding Levels During Entire Period Short-term Probabilistic Guidance (Experimental)

Auto Refresh: OFF

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

NOTE: Forecasts for the Potomac River at Point of Rocks 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: 20 Flood Stage: 16 Action Stage: 11 Low Stage (in feet): -9999 Historic Crests (1) 41.03 ft on 03/19/1936 (2) 40.43 ft on 10/16/1942 (3) 40.20 ft on 06/02/1889 (4) 37.43 ft on 06/23/1972 (5) 36.34 ft on 01/21/1996 Show More Historic Crests (P): Preliminary values subject to further review. Recent Crests (1) 18.29 ft on 05/09/2022 (P) (2) 16.39 ft on 03/02/2021 (3) 22.40 ft on 12/17/2018 (4) 21.39 ft on 09/29/2018 (5) 19.92 ft on 09/11/2018 Show More Recent Crests (P): Preliminary values subject to further review. Low Water Records (1) 0.30 ft on 09/11/1966 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
40	Water reaches the lowest portion of the city of Brunswick, above the railroad tracks.
35	The MARC station in Point of Rocks is flooded. At least two feet of water covers much of Maryland State Route 28 in the city. Water begins to enter homes and businesses in Point of Rocks along Route 28.
32	Water covers Maryland State Route 28 in Point of Rocks near the MARC station.
31	Water reaches the MARC parking lot at Brunswick.
30	Water reaches a home on the Loudoun County side of the river near Point of Rocks. Water also reaches the Brunswick train yard and covers portions of the MARC parking lot at Point of Rocks, and covers Old Commerce Street in Point of Rocks.
29	Water completely covers the comfort station at the Point of Rocks boat ramp.
27	Water covers a large section of the C&O Canal towpath in Frederick County, Maryland. Water also reaches the railroad tracks at Point of Rocks.
25	Water reaches outbuildings on the Loudoun County side of the river near Point of Rocks.
23	Floodwaters completely cover the comfort station at the Brunswick boat ramp, and reach the comfort station at the Point of Rocks boat ramp. The upper parking lot at the Point of Rocks boat ramp begins to flood.
22	Water begins to cover the C&O Canal towpath near Point of Rocks and Brunswick.
20	The boat ramp and lower parking lot at Point of Rocks are flooded. Water approaches the water treatment plant in Brunswick. Farmland behind the Tarara Vineyard is flooded.
18	Water approaches structures at the Brunswick campground.
17	Water enters the comfort station at the Brunswick boat ramp parking area.
16	The parking lots at both the McKimmey and Brunswick boat ramps begin to flood. Flooding of an agricultural field adjacent to the McKimmey boat ramp is occurring. About half the lower parking lot of the Point of Rocks boat ramp is also flooded.
15	Several lowland forested areas, mainly on islands, begin to flood.
14	Water completely covers the Nolands Ferry boat ramp and begins to flood the parking lot nearby.
13	Water begins to cover low lying areas within the Brunswick campground.
12.5	The Point of Rocks boat ramp is completely covered by water, and water begins to affect the lower parking lot nearby.
11	Water covers the parking lot of the Lander boat ramp. Campers and other recreational interests should begin to move away from the river.
5.5	The river reaches danger level for boaters, as defined by the State of Maryland. Conditions are extremely hazardous.
2	The river reaches caution level for boaters, as defined by the State of Maryland. Fast moving water and changing currents can be expected.
Photos (1) USGS Wellhouse Adjacent to US Route 15 at Point of Rocks (2) Staff Gage Being Installed in 1993 on US Route 15 Bridge Support Beam (3) Looking Upstream at Paton Island from US 15 Bridge (4) Railroad Tunnel Just Above Gage on Maryland Side of Potomac

About This Location

Latitude: 39.273611° N, Longitude: 77.543056° W, Horizontal Datum: NAD83/WGS84 River Stage Reference Frame Gauge Height Flood Stage Uses NWS stage 0 ft 16 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 29 200.63 ft 216.63 ft 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: U.S. Geological Survey (USGS) Data and Site Info for Point of Rocks

Additional Information

Potential River Levels Used to Estimate the Chance of Flooding and the Range of Possible River Levels 10 Day (HEFS) 7 Day (NAEFS) 7 Day (GEFS) Note: Use the official hydrograph at the top of this web page for river levels within the next 72 hours. Click individual graphics to enlarge.

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