Potomac River near Washington DC (Little Falls)
No watches, warnings or advisories are in effect for this area.
Future / Actual / Minor
OWP 2.0 WWA Modal Title
01/11/2021, 10:04 PM UTC through 01/11/2021, 10:04 PM UTC
Sender
Sent
- Warning: no valid ratings curve available. Transformations to and from FEET/CFS/KCFS will not happen.
Traces and Thresholds Click to turn on/off display
Observed (OBS) 03/28/2025 3:45 PM EDTOfficial Forecast (FCST) 03/28/2025 9:31 AM EDTRecord: 28.1 ftCATEGORY STAGE 
Major Flooding 14 ft Moderate Flooding 12 ft Minor Flooding 10 ft Action 5 ft Reliability of the Forecast:
NOTE: Forecasts are issued routinely year-round.
National Water Model Hydrograph
Official NWS streamflow forecasts are produced by NWS hydrologic forecasters for river gauge locations using hydrologic models which are calibrated to that location. This process considers additional guidance and information, including local expertise and experience, to produce the best forecast possible. The NWM output provides supplemental guidance to NWS forecasters and should not be considered an official NWS river forecast.
Flood Impacts
- 17 - Water overflows the overlooks at Great Falls National Park and approaches the lower level of the visitors center. Most of the C&O Canal towpath downstream of Pennyfield is flooded. There is approximately a foot of water in the clubhouse on Sycamore Island.
- 16 - Water reaches the clubhouse on Sycamore Island.
- 15 - Most of the C&O Canal towpath from Pennyfield downstream is flooded.
Gauge Info
| Coordinates | 38.9497, -77.1278 |
| RFC | MARFC |
| State | MD |
| WFO | LWX |
| County | Montgomery |
| Data Provider(s) | |
| US Geological Survey | USGS--Water Resources of the United States |
| USGS | 01646500 |
Gauge Location
Recent Crests
| 1. | 10.16 ft | on 05-09-2022 | (P) |
| 2. | 11.56 ft | on 12-17-2018 | |
| 3. | 11.01 ft | on 09-29-2018 | |
| 4. | 10.85 ft | on 09-11-2018 | |
| 5. | 12.38 ft | on 06-05-2018 |
Recent Crests
| 1. | 10.16 ft | on 05-09-2022 | (P) |
| 2. | 11.56 ft | on 12-17-2018 | |
| 3. | 11.01 ft | on 09-29-2018 | |
| 4. | 10.85 ft | on 09-11-2018 | |
| 5. | 12.38 ft | on 06-05-2018 | |
| 6. | 11.70 ft | on 05-18-2014 | |
| 7. | 10.33 ft | on 10-31-2012 | |
| 8. | 9.78 ft | on 09-09-2011 | |
| 9. | 11.30 ft | on 05-20-2011 | |
| 10. | 11.68 ft | on 04-18-2011 | |
| 11. | 10.88 ft | on 03-12-2011 | |
| 12. | 12.82 ft | on 03-15-2010 | |
| 13. | 11.17 ft | on 01-27-2010 | |
| 14. | 9.67 ft | on 05-06-2009 | |
| 15. | 10.04 ft | on 05-13-2008 | |
| 16. | 9.43 ft | on 04-17-2007 | |
| 17. | 10.28 ft | on 03-30-2005 | |
| 18. | 10.87 ft | on 12-12-2003 | |
| 19. | 9.97 ft | on 09-23-2003 | (P) |
| 20. | 11.44 ft | on 09-21-2003 | |
| 21. | 10.79 ft | on 03-22-1998 | |
| 22. | 10.43 ft | on 01-10-1998 | |
| 23. | 17.84 ft | on 09-08-1996 | |
| 24. | 19.29 ft | on 01-21-1996 | |
| 25. | 10.37 ft | on 03-30-1994 | |
| 26. | 10.09 ft | on 11-29-1993 | |
| 27. | 10.55 ft | on 04-18-1993 | |
| 28. | 10.16 ft | on 03-25-1993 | |
| 29. | 12.35 ft | on 03-06-1993 | |
| 30. | 10.13 ft | on 01-29-1993 | |
| 31. | 11.41 ft | on 04-19-1987 | |
| 32. | 10.09 ft | on 03-16-1986 | |
| 33. | 17.99 ft | on 11-07-1985 | |
| 34. | 10.74 ft | on 03-30-1984 | |
| 35. | 13.73 ft | on 02-16-1984 | |
| 36. | 13.12 ft | on 02-26-1979 | |
| 37. | 10.83 ft | on 03-16-1978 | |
| 38. | 10.47 ft | on 01-28-1978 | |
| 39. | 13.18 ft | on 10-11-1976 | |
| 40. | 13.39 ft | on 09-27-1975 | |
| 41. | 12.23 ft | on 03-21-1975 | |
| 42. | 10.36 ft | on 12-28-1973 | |
| 43. | 22.03 ft | on 06-24-1972 | |
| 44. | 11.48 ft | on 03-09-1967 | |
| 45. | 11.59 ft | on 05-01-1964 | 1 |
| 46. | 11.85 ft | on 03-06-1964 | 1 |
| 47. | 13.91 ft | on 03-21-1963 | 1 |
| 48. | 11.64 ft | on 03-15-1963 | 1 |
| 49. | 12.87 ft | on 03-07-1963 | 1 |
| 50. | 13.43 ft | on 03-23-1962 | 1 |
| 51. | 11.42 ft | on 03-14-1962 | 1 |
| 52. | 11.05 ft | on 03-01-1962 | 1 |
| 53. | 10.37 ft | on 04-18-1961 | 1 |
| 54. | 11.71 ft | on 04-14-1961 | 1 |
| 55. | 12.23 ft | on 02-27-1961 | 1 |
| 56. | 13.15 ft | on 02-21-1961 | 1 |
| 57. | 13.66 ft | on 05-10-1960 | 1 |
| 58. | 13.35 ft | on 04-06-1960 | 1 |
| 59. | 12.29 ft | on 04-01-1960 | 1 |
| 60. | 12.02 ft | on 05-07-1958 | 1 |
| 61. | 11.19 ft | on 03-29-1958 | 1 |
| 62. | 10.18 ft | on 03-01-1958 | 1 |
| 63. | 11.40 ft | on 04-07-1957 | 1 |
| 64. | 11.10 ft | on 02-12-1957 | 1 |
| 65. | 10.75 ft | on 07-21-1956 | 1 |
| 66. | 17.60 ft | on 08-20-1955 | 1 |
| 67. | 11.47 ft | on 03-23-1955 | 1 |
| 68. | 13.30 ft | on 10-17-1954 | 1 |
| 69. | 10.46 ft | on 04-09-1954 | 1 |
| 70. | 12.47 ft | on 03-03-1954 | 1 |
| 71. | 11.44 ft | on 03-26-1953 | 1 |
| 72. | 13.76 ft | on 11-23-1952 | 1 |
| 73. | 12.09 ft | on 06-15-1952 | 1 |
| 74. | 14.17 ft | on 04-29-1952 | 1 |
| 75. | 11.95 ft | on 03-13-1952 | 1 |
| 76. | 12.48 ft | on 12-09-1950 | 1 |
| 77. | 13.85 ft | on 12-06-1950 | 1 |
| 78. | 10.26 ft | on 07-19-1949 | 1 |
| 79. | 13.00 ft | on 06-20-1949 | 1 |
| 80. | 10.69 ft | on 04-16-1948 | 1 |
| 81. | 10.69 ft | on 02-16-1948 | 1 |
| 82. | 13.88 ft | on 09-20-1945 | 1 |
| 83. | 13.15 ft | on 12-31-1942 | 1 |
| 84. | 26.88 ft | on 10-17-1942 | 1 |
| 85. | 13.17 ft | on 05-24-1942 | 1 |
| 86. | 11.29 ft | on 04-22-1940 | 1 |
| 87. | 12.60 ft | on 02-05-1939 | 1 |
| 88. | 15.62 ft | on 10-30-1937 | 1 |
| 89. | 10.10 ft | on 08-27-1937 | 1 |
| 90. | 23.30 ft | on 04-28-1937 | 1 |
| 91. | 10.58 ft | on 02-23-1937 | 1 |
| 92. | 10.50 ft | on 01-24-1937 | 1 |
| 93. | 28.10 ft | on 03-19-1936 | 1 |
| 94. | 11.16 ft | on 03-13-1936 | 1 |
| 95. | 14.69 ft | on 02-27-1936 | 1 |
| 96. | 10.37 ft | on 02-17-1936 | 1 |
| 97. | 13.50 ft | on 12-02-1934 | 1 |
| 98. | 10.57 ft | on 08-25-1933 | 1 |
| 99. | 12.80 ft | on 04-22-1933 | 1 |
| 100. | 10.15 ft | on 04-19-1933 | 1 |
| 101. | 15.25 ft | on 05-14-1932 | 1 |
Historic Crests
| 1. | 28.10 ft | on 03-19-1936 | 1 |
| 2. | 26.88 ft | on 10-17-1942 | 1 |
| 3. | 23.30 ft | on 04-28-1937 | 1 |
| 4. | 22.03 ft | on 06-24-1972 | |
| 5. | 19.29 ft | on 01-21-1996 |
Historic Crests
| 1. | 28.10 ft | on 03-19-1936 | 1 |
| 2. | 26.88 ft | on 10-17-1942 | 1 |
| 3. | 23.30 ft | on 04-28-1937 | 1 |
| 4. | 22.03 ft | on 06-24-1972 | |
| 5. | 19.29 ft | on 01-21-1996 | |
| 6. | 17.99 ft | on 11-07-1985 | |
| 7. | 17.84 ft | on 09-08-1996 | |
| 8. | 17.60 ft | on 08-20-1955 | 1 |
| 9. | 15.62 ft | on 10-30-1937 | 1 |
| 10. | 15.25 ft | on 05-14-1932 | 1 |
| 11. | 14.69 ft | on 02-27-1936 | 1 |
| 12. | 14.17 ft | on 04-29-1952 | 1 |
| 13. | 13.91 ft | on 03-21-1963 | 1 |
| 14. | 13.88 ft | on 09-20-1945 | 1 |
| 15. | 13.85 ft | on 12-06-1950 | 1 |
| 16. | 13.76 ft | on 11-23-1952 | 1 |
| 17. | 13.73 ft | on 02-16-1984 | |
| 18. | 13.66 ft | on 05-10-1960 | 1 |
| 19. | 13.50 ft | on 12-02-1934 | 1 |
| 20. | 13.43 ft | on 03-23-1962 | 1 |
| 21. | 13.39 ft | on 09-27-1975 | |
| 22. | 13.35 ft | on 04-06-1960 | 1 |
| 23. | 13.30 ft | on 10-17-1954 | 1 |
| 24. | 13.18 ft | on 10-11-1976 | |
| 25. | 13.17 ft | on 05-24-1942 | 1 |
| 26. | 13.15 ft | on 02-21-1961 | 1 |
| 27. | 13.15 ft | on 12-31-1942 | 1 |
| 28. | 13.12 ft | on 02-26-1979 | |
| 29. | 13.00 ft | on 06-20-1949 | 1 |
| 30. | 12.87 ft | on 03-07-1963 | 1 |
| 31. | 12.82 ft | on 03-15-2010 | |
| 32. | 12.80 ft | on 04-22-1933 | 1 |
| 33. | 12.60 ft | on 02-05-1939 | 1 |
| 34. | 12.48 ft | on 12-09-1950 | 1 |
| 35. | 12.47 ft | on 03-03-1954 | 1 |
| 36. | 12.38 ft | on 06-05-2018 | |
| 37. | 12.35 ft | on 03-06-1993 | |
| 38. | 12.29 ft | on 04-01-1960 | 1 |
| 39. | 12.23 ft | on 02-27-1961 | 1 |
| 40. | 12.23 ft | on 03-21-1975 | |
| 41. | 12.09 ft | on 06-15-1952 | 1 |
| 42. | 12.02 ft | on 05-07-1958 | 1 |
| 43. | 11.95 ft | on 03-13-1952 | 1 |
| 44. | 11.85 ft | on 03-06-1964 | 1 |
| 45. | 11.71 ft | on 04-14-1961 | 1 |
| 46. | 11.70 ft | on 05-18-2014 | |
| 47. | 11.68 ft | on 04-18-2011 | |
| 48. | 11.64 ft | on 03-15-1963 | 1 |
| 49. | 11.59 ft | on 05-01-1964 | 1 |
| 50. | 11.56 ft | on 12-17-2018 | |
| 51. | 11.48 ft | on 03-09-1967 | |
| 52. | 11.47 ft | on 03-23-1955 | 1 |
| 53. | 11.44 ft | on 03-26-1953 | 1 |
| 54. | 11.44 ft | on 09-21-2003 | |
| 55. | 11.42 ft | on 03-14-1962 | 1 |
| 56. | 11.41 ft | on 04-19-1987 | |
| 57. | 11.40 ft | on 04-07-1957 | 1 |
| 58. | 11.30 ft | on 05-20-2011 | |
| 59. | 11.29 ft | on 04-22-1940 | 1 |
| 60. | 11.19 ft | on 03-29-1958 | 1 |
| 61. | 11.17 ft | on 01-27-2010 | |
| 62. | 11.16 ft | on 03-13-1936 | 1 |
| 63. | 11.10 ft | on 02-12-1957 | 1 |
| 64. | 11.05 ft | on 03-01-1962 | 1 |
| 65. | 11.01 ft | on 09-29-2018 | |
| 66. | 10.88 ft | on 03-12-2011 | |
| 67. | 10.87 ft | on 12-12-2003 | |
| 68. | 10.85 ft | on 09-11-2018 | |
| 69. | 10.83 ft | on 03-16-1978 | |
| 70. | 10.79 ft | on 03-22-1998 | |
| 71. | 10.75 ft | on 07-21-1956 | 1 |
| 72. | 10.74 ft | on 03-30-1984 | |
| 73. | 10.69 ft | on 04-16-1948 | 1 |
| 74. | 10.69 ft | on 02-16-1948 | 1 |
| 75. | 10.58 ft | on 02-23-1937 | 1 |
| 76. | 10.57 ft | on 08-25-1933 | 1 |
| 77. | 10.55 ft | on 04-18-1993 | |
| 78. | 10.50 ft | on 01-24-1937 | 1 |
| 79. | 10.47 ft | on 01-28-1978 | |
| 80. | 10.46 ft | on 04-09-1954 | 1 |
| 81. | 10.43 ft | on 01-10-1998 | |
| 82. | 10.37 ft | on 04-18-1961 | 1 |
| 83. | 10.37 ft | on 02-17-1936 | 1 |
| 84. | 10.37 ft | on 03-30-1994 | |
| 85. | 10.36 ft | on 12-28-1973 | |
| 86. | 10.33 ft | on 10-31-2012 | |
| 87. | 10.28 ft | on 03-30-2005 | |
| 88. | 10.26 ft | on 07-19-1949 | 1 |
| 89. | 10.18 ft | on 03-01-1958 | 1 |
| 90. | 10.16 ft | on 05-09-2022 | (P) |
| 91. | 10.16 ft | on 03-25-1993 | |
| 92. | 10.15 ft | on 04-19-1933 | 1 |
| 93. | 10.13 ft | on 01-29-1993 | |
| 94. | 10.10 ft | on 08-27-1937 | 1 |
| 95. | 10.09 ft | on 11-29-1993 | |
| 96. | 10.09 ft | on 03-16-1986 | |
| 97. | 10.04 ft | on 05-13-2008 | |
| 98. | 9.97 ft | on 09-23-2003 | (P) |
| 99. | 9.78 ft | on 09-09-2011 | |
| 100. | 9.67 ft | on 05-06-2009 | |
| 101. | 9.43 ft | on 04-17-2007 |
Vertical Datum Table
| type | NAVD88 |
|---|---|
| major Flooding | 51.20 ft |
| moderate Flooding | 49.20 ft |
| minor Flooding | 47.20 ft |
| action | 42.20 ft |
| Latest Value | 40.61 ft |
| Gauge Zero | 37.20 ft |
Gauge Photos
No Images Found
Unique Local Info
|
Potential River Levels Used to Estimate the Chance of Flooding and the Range of Possible River Levels |
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| 10 Day (HEFS) | 7 Day (NAEFS) | 7 Day (GEFS) |
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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
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.
Resources
Hydrologic Resource Links
Additional Resource Links
WFO Information
Weather Forecast Office
(Baltimore/Washington) Sterling
43858 Weather Service Rd.
Sterling, VA 20166
Official Homepage