Rivers in Pennsylvania
Monongahela River at Grays Landing Lock and Dam
Below flood stage
13.25ftStage
Observed Thu, Sep 24, 4:01 AM EDT
- Flood stage
- 21.00 ft
- Forecast crest
- 13.50 ftSun, Sep 27, 2:00 AM EDT
- Record crest
- 36.00 ft1888
Flood stages and impacts
| Category | Stage |
|---|---|
| Major flood | 27.00 ft |
| Moderate flood | 25.00 ft |
| Minor flood | 21.00 ft |
| Action | 15.00 ft |
- 36.00 ftWater reaches the flood of record...July 1, 1888.
- 35.00 ftFlood waters reach the historic log cabin along Front Street in Greensboro.
- 34.00 ftFlood waters reach the corner of Front and County Streets in Greensboro.
- 31.00 ftFlood waters reach the Bed and Breakfast on County Street in Greensboro.
- 30.50 ftWater reaches level of the November 5, 1985 flood.
- 28.40 ftWater reaches the level of the St. Patricks Day Flood and crest on March 18, 1936.
- 25.80 ftWater reaches the level reached during the rain and snowmelt flood on January 20, 1996.
- 25.00 ftFlood waters reach Martin Ferry Road in the village of Glasworks.
- 24.00 ftThe lock walls are overtopped at Grays Landing Lock and Dam.
- 23.95 ftWater levels reach the flood levels of the flood of July 29, 2017.
- 22.78 ftWater reaches the level reached on March 4, 2015.
- 21.00 ftThe lock at Grays Landing Lock and Dam goes out of service, and navigation is suspended.
- 19.00 ftThe bike trail floods in Greensboro near County Street.
Flood outlook
Chance of flooding, September to November
| Category | Chance |
|---|---|
| Minor flooding | 8% |
| Moderate flooding | Under 5% |
| Major flooding | Under 5% |
The three-month chances are the River Forecast Centers’ long-range flood outlook, issued September 22, 2026.
Crest history
29 crests on NOAA’s list since 1888.
| # | Date | Stage |
|---|---|---|
| 1 | July 1, 1888 | 36.00 ft |
| 2 | November 5, 1985 | 30.50 ft |
| 3 | March 18, 1936 | 28.40 ft |
| 4 | January 20, 1996 | 25.80 ft |
| 5 | February 19, 2000 | 24.50 ft |
| 6 | July 29, 2017 | 23.95 ft |
| 7 | March 4, 2015 | 22.78 ft |
| 8 | February 17, 2018 | 22.07 ft |
| 9 | March 1, 2021 | 21.77 ft |
| 10 | December 14, 2007 | 21.70 ft |
| 11 | December 14, 2007 | 21.37 ft |
| 12 | April 4, 2024 | 21.02 ft |
| 13 | May 4, 2009 | 21.00 ft |
| 14 | March 21, 2002 | 20.70 ft |
| 15 | January 26, 2010 | 20.60 ft |
| 16 | November 23, 2011 | 20.09 ft |
| 17 | March 7, 2004 | 19.34 ft |
| 18 | April 16, 2007 | 19.31 ft |
| 19 | June 5, 2008 | 19.27 ft |
| 20 | February 23, 2003 | 19.00 ft |
| 21 | May 31, 2025 | 18.95 ft |
| 22 | September 28, 2018 | 18.80 ft |
| 23 | January 13, 2018 | 18.70 ft |
| 24 | March 15, 2015 | 18.51 ft |
| 25 | September 10, 2018 | 18.05 ft |
Most recent crests
- May 31, 2025: 18.95 ft
- April 4, 2024: 21.02 ft
- March 1, 2021: 21.77 ft
- July 1, 2019: 16.40 ft
- February 13, 2019: 15.88 ft
- February 8, 2019: 16.85 ft
- January 20, 2019: 17.06 ft
- September 28, 2018: 18.80 ft
- September 10, 2018: 18.05 ft
- February 17, 2018: 22.07 ft
Nearby
Upstream, downstream and the gauges around this one.
What this means
Forecasts by the Ohio River Forecast Center. Forecasts are issued routinely year-round. The above river forecast includes future rainfall/snowmelt. Forecast stages may be different if the actual rainfall/snowmelt is different than the forecast rainfall/snowmelt. Stage may be affected by ice.
Sources
Stage, flood stages, impacts and crest history from NOAA’s National Water Prediction Service. Streamflow and the daily record from the U.S. Geological Survey.