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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 Potomac River at Hancock are issued routinely year-round.
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Upstream Gauge - at Paw Paw Upstream Gauge
Zoom Level:14
Flood Categories (in feet)
Major Flood Stage: 35
Moderate Flood Stage: 33
Flood Stage: 25
Action Stage: 21
Low Stage (in feet): -9999

Historic Crests
(1) 47.60 ft on 03/18/1936
(2) 41.20 ft on 11/06/1985
(3) 40.00 ft on 06/01/1889
(4) 36.63 ft on 10/16/1942
(5) 36.26 ft on 01/20/1996
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(P): Preliminary values subject to further review.

Recent Crests
(1) 23.57 ft on 12/16/2018
(2) 26.38 ft on 06/04/2018
(3) 21.33 ft on 05/17/2014
(4) 25.41 ft on 05/19/2011
(5) 25.94 ft on 03/14/2010
Show More Recent Crests

(P): Preliminary values subject to further review.

Low Water Records
(1) 2.00 ft on 10/04/1932
(2) 2.12 ft on 09/12/1966
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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
56 Water approaches the highest point on Main Street.
46 Water floods the railroad depot.
45 Floodwater isolates the town of Hancock.
40 Water floods 25 to 30 homes along the West Virginia side of the river just downstream from Hancock, and at least another 20 to 30 in Hancock itself.
35 Water inundates 20 to 30 homes and 5 or more businesses in the west end of Hancock.
33 Water floods low spots on East Main Street in Hancock.
31 Water begins to flood low spots of West Main Street in Hancock.
30 Water begins to inundate homes and business in Hancock. Water covers the road to the maintenance shop for the National Park Service near Hancock. The west end of the Potomac Airpark runway begins to flood.
28 Water begins to inundate some yards on the west end of Hancock. Water also begins to collect on the west end of the CSX Railyard on the West Virginia side.
25 Water may begin to inundate low points of the CSX Railroad tracks on the West Virginia side of the river due to backwater. Additionally, access to Potomac Airpark may be restricted due to backwater. Water reaches the top of the Hancock boat ramp and begins to spill over into the adjacent parking lot.
24 Water begins to overflow into low lying areas.
21 The boat ramp at Four Locks is covered by water. Half the parking lot there is also covered.
7.5 The river is at danger level for boaters as defined by the State of Maryland. At these levels, conditions are extremely hazardous.
3.5 The river reaches caution level for boaters as defined by the State of Maryland. Fast moving water and changing currents can be expected.

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) 10 Day (NAEFS) 10 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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