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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 Monocacy River near Frederick at Interstate 70 are issued routinely year-round.
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Zoom Level:14
Flood Categories (in feet)
Major Flood Stage: 20
Moderate Flood Stage: 17
Flood Stage: 15
Action Stage: 13
Low Stage (in feet): -9999

Historic Crests
(1) 35.90 ft on 06/23/1972
(2) 30.80 ft on 09/26/1975
(3) 28.10 ft on 08/24/1933
(4) 25.38 ft on 10/10/1976
(5) 23.67 ft on 01/20/1996
Show More Historic Crests

(P): Preliminary values subject to further review.

Recent Crests
(1) 19.04 ft on 09/24/2021
(2) 22.10 ft on 09/02/2021
(3) 15.83 ft on 05/01/2020 (P)
(4) 16.62 ft on 05/06/2019
(5) 16.59 ft on 03/22/2019
Show More Recent Crests

(P): Preliminary values subject to further review.

Low Water Records
(1) 0.50 ft on 09/11/1966
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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
30 Water reaches the second floor of Gambrill Mill on the Monocacy National Battlefield.
24 Water approaches Urbana Pike near Monocacy National Battlefield.
21 Maryland Route 26 is flooded near the Monocacy River bridge.
20 Water reaches Gambrill Mill on the Monocacy National Battlefield.
17 Significant lowland flooding is occurring along the river, with backwater flooding also occurring. Numerous roads are closed. Water is approaching the parking lot at Gambrill Mill on the Monocacy National Battlefield. Backwater flooding from Carroll Creek is likely approaching the underside of the bridge leading to the Frederick city wastewater treatment plant.
16 Much of Pinecliff Park and Rivermist Park in Frederick are flooded. Buckeystown Community Park is also flooded with water approaching the parking lot. Waters are also approaching the Frederick city wastewater treatment plant and the Ballenger Creek wastewater treatment plant. Significant backwater flooding is occurring. Several roads will be closed along the river and adjoining creeks.
15 Both banks of the river are flooded. Water begins to flood low-lying fields at Monocacy National Battlefield. Water reaches the access road of the Frederick city wastewater treatment plant. Backwater flooding is occurring on several area creeks, particularly Carroll Creek in Frederick.
14 Two low-water crossings, one on Michaels Mill Road /State Route 880/ in Buckeystown, and one on Retreat Road north of Frederick, begin to flood.
13 Water covers portions of Pinecliff Park in southeast Frederick. Water also approaches Rivermist Park in northeast Frederick.
10 The east side of the Monocacy River, or left bank, begins to flood east of Frederick. Although no structures are affected, water approaches an access road at Pinecliff Park.
5 After rain events, the river may become hazardous for recreational purposes when stages are over 5 feet.

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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