The National Weather Service's National Water Prediction Service (NWPS) is an online tool for accessing real-time (observed) and forecasted streamflow and gage height information for specific flood forecast points.

Streamflow, radar and runoff modeling are incorporated to provide updated, graphical flood forecast information.

In normal (non-flood) conditions, these pages are updated every 1-3 days; during times of flood, updates occur several times a day.

Note: the NWPS replaced the Advanced Hydrologic Prediction Service (AHPS) in late March 2024.

The NWPS issues forecasts for locations along the Upper Delaware River, including:

• Callicoon
  
  
• Barryville
  
  
• Matamoras/Port Jervis
  
  
• Montague

Interactive Map (Includes locations on several tributaries as well as the four flood forecast points on the Delaware River listed above)

The NWPS issues forecasts for the following locations along the Delaware River:

• Tocks Island
  
  
• Belvidere
  
  
• Easton
  
  
• Riegelsville
  
  
• Frenchtown
  
  
• Stockton
  
  
• New Hope-Lambertville Bridge
  
  
• Washington Crossing
  
  
• Trenton

Interactive Map (Includes locations on several tributaries as well as the nine forecast points on the Delaware River listed above)

The NWPS issues forecasts for the following locations along the tidal Delaware River:

• Newbold Island
  
  
• Burlington, NJ
  
  
• Bridesburg, PA
  
  
• Washington Street, Phila., PA
  
  
• Marcus Hook, PA
  
  
• Delaware City, DE
  
  
• Delaware Bay at Reedy Point, DE
  
  
• Delaware Bay at Lewes, DE
  
  
• Delaware Bay at Cape May, NJ

Interactive Map (Includes locations on the Schuylkill River and several other tributaries as well as the nine forecast points on the tidal Delaware River listed above)

Flood inundation maps provide information on the spatial extent of flood waters in the vicinity of NWS river forecast locations.

Users are able to display flood inundation maps for various levels ranging from minor flooding through the largest observed flood.

Flood inundation maps, combined with river observations and NWS forecasts, enhance the communication of flood risk and provide users additional information needed to better mitigate the impacts of flooding and plan for more resilient communities.

Flood inundation maps are now available for the following nine flood forecast locations along the Delaware River main stem as well as the Assunpink Creek at Trenton, N.J. :

• Matamoras/Port Jervis
  
  
• Montague
  
  
• Belvidere
  
  
• Easton
  
  
• Riegelsville
  
  
• Frenchtown
  
  
• Stockton
  
  
• New Hope-Lambertville
  
  
• Trenton

• Understanding the River Forecast Process (MARFC; pdf 940 KB)
  
  
• Uncertainty in River Forecasts (MARFC; pdf 1.9 MB)
  
  
• NWS Inundation Mapping User Guide (NWS; pdf 25 MB)