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This probabilistic forecast is issued by the Middle Atlantic River Forecast Center.
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About this graph
Forecasts for the South Branch Potomac River near Petersburg are issued routinely year-round.
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Upstream Gauge - at Franklin Upstream Gauge Downstream Gauge Downstream Gauge - near Springfield
Zoom Level:14
Flood Categories (in feet)
Major Flood Stage: 17
Moderate Flood Stage: 15
Flood Stage: 14
Action Stage: 12
Low Stage (in feet): -9999

Historic Crests
(1) 22.83 ft on 06/17/1949
(2) 22.20 ft on 09/06/1996
(3) 21.80 ft on 11/05/1985
(4) 21.20 ft on 11/24/1877
(5) 20.30 ft on 03/17/1936
Show More Historic Crests

(P): Preliminary values subject to further review.

Recent Crests
(1) 12.25 ft on 03/01/2021
(2) 16.93 ft on 04/16/2018
(3) 14.38 ft on 05/16/2014
(4) 12.80 ft on 05/08/2013
(5) 11.80 ft on 05/18/2011
Show More Recent Crests

(P): Preliminary values subject to further review.

Low Water Records
(1) 0.40 ft on 08/20/1988
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Gauge LocationGauge Map Marker
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
22.5 Significant flooding is occurring. More than a hundred buildings in Petersburg are flooded.
20 Several city blocks on the south side of Petersburg are flooded. Backwater may also flood portions of the eastern sections of the city.
18 Water covers the entire runway at Grant County Airport and is in nearby structures. Hundreds of acres of lowlands are flooded. Water approaches homes on the north side of the river in Petersburg.
17 Water reaches structures at the Grant County Airport. Flooding also begins south of the river on the south side of Petersburg.
15 Two structures are flooded upstream of Petersburg. Water also approaches the runway at the Petersburg Airport.
14 Water approaches structures upstream of Petersburg. Water also begins to cover Fish Hatchery Road near the river.
12 Water overflows the natural banks into nearby lowlands. River Road alongside the river begins to flood in its lowest spots.

Other Real-time and/or Archive Data Sources:

Additional Information Collapse
Potential River Levels - Used to
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)
HEFS Ensemble NAEFS Ensemble GEFS Ensemble

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.

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
(Baltimore/Washington) Sterling Weather Forecast Office
43858 Weather Service Rd.
Sterling, VA 20166
(571) 888-3500
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Page last modified: 2-Nov-2020 7:30 PM
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