Changes to Flood Stages and Forecast and Warning Services on the Potomac River

Following collaboration with our Emergency Management and National Park Service partners, the National Weather Service (NWS) Baltimore/Washington Forecast Office will make several changes along portions of the Potomac River during the winter of 2019/2020.  These changes are outlined below, from west to east:

Paw Paw, West Virginia

Since the floods of 1996, which caused extensive damage in the town of Paw Paw, several buildings have been removed from the floodplain. Although minor flooding still occurs at the same levels it has for decades, there are now fewer structures close to the river. Therefore, moderate flooding (defined as the point generally where structures are affected) and major flooding (defined as the most extreme events in the historical record, with widespread damage and evacuations) require higher water levels in order to occur.  

Effective Wednesday, January 8th, 2020, flood categories at Paw Paw will change as follows:

Hancock, Maryland

Through analysis by the Morgan County Emergency Management Agency, and observations during a high water event in 2018, it has been determined that the existing minor flood stage of 30 feet (the point at which roads or public property begins to be affected) is significantly too high. The previous flood stage was based on impacts directly within the town of Hancock, not within neighboring areas, which flood sooner.

Effective Wednesday, January 8th, 2020, flood categories at Hancock will change as follows:

This means that if the river at Hancock exceeds, or is forecast to exceed 25 feet -- instead of 30 -- a Flood Warning will be issued by the National Weather Service for portions of Morgan and Washington Counties.

Williamsport / Dam Number Five, MD

Beginning December 11th, 2019, the National Weather Service (NWS) Baltimore/Washington forecast office and the Middle Atlantic River Forecast Center (MARFC) in State College, Pennsylvania, began providing enhanced river forecast and warning services for portions of the Potomac River near Williamsport, Maryland, including most of Berkeley County, West Virginia.

For additional details on this new service and associated flood levels, visit https://www.weather.gov/lwx/PotomacWilliamsport.

Point of Rocks, Maryland

In 2018, the river gauge at Point of Rocks recorded a "major flood" based on existing flood categories.  On site surveys by National Weather Service personnel determined no flooding that would reach the major threshold actually occurred.  Following a meeting with our emergency management partners, it was agreed to raise the major flood level slightly to better encompass events where significant flooding would occur.  The Action Stage will be lowered by several feet due to impacts to C&O Canal property which occur at these lower levels, but Flood Warnings will still be issued for the minor flood level of 16 feet.

Effective Wednesday, January 8th, 2020, flood categories at Point of Rocks will change as follows:

For additional information:

River observations (and where available, forecasts) regionwide are available at http://weather.gov/washington by choosing the Rivers and Lakes icon, which is below the map on the main page, or immediately below this sentence on this page.