National Weather Service United States Department of Commerce

Powerful Pacific System Impacting the West; First Significant Snow for Portions of the East

Power Pacific system will continue to bring significant impacts for Pacific Northwest into northern California the remainder of the week. Dangerous coastal affects, heavy rain, flooding, strong winds, and higher elevation mountain snow continues. Meanwhile, a storm across the east is set to bring the first accumulating snow to many higher elevations of the Catskills into the central Appalachians. Read More >

Tidal Inundation Mapping


All heights on this map are in NAVD88 elevation. To correlate this value to local datums of tide gauges, such as Mean Lower Low Water (MLLW) or Washington Mean Low Water (WMLW) in your area, click on the tab above corresponding to the elevation you select.

Disclaimer:  These maps are only valid when there is no freshwater flooding occurring.  In the event of freshwater flooding on the Potomac River, users should consult the freshwater inundation maps located at these links:
Georgetown/Rosslyn areas:

https://water.weather.gov/ahps2/inundation/index.php?gage=gtnd2
Downtown DC/Potomac Park/Reagan Airport/Anacostia:
https://water.weather.gov/ahps2/inundation/index.php?gage=wasd2
Alexandria/Belle View/National Harbor/JBAB (south half):
https://water.weather.gov/ahps2/inundation/index.php?gage=axtv2

NAVD88 Elevation 2.0 ft
Georgetown (GTND2) 4.26 ft (WMLW)
SW Waterfront (WASD2) 3.4 ft (MLLW)
Alexandria (AXTV2) 2.0 ft
Anacostia (ANAD2) 2.0 ft
NAVD88 Elevation 2.5 ft
Georgetown (GTND2) 4.76 ft (WMLW)
SW Waterfront (WASD2) 3.9 ft (MLLW)
Alexandria (AXTV2) 2.5 ft
Anacostia (ANAD2) 2.5 ft
NAVD88 Elevation 3.0 ft
Georgetown (GTND2) 5.26 ft (WMLW)
SW Waterfront (WASD2) 4.4 ft (MLLW)
Alexandria (AXTV2) 3.0 ft
Anacostia (ANAD2) 3.0 ft
NAVD88 Elevation 3.5 ft
Georgetown (GTND2) 5.76 ft (WMLW)
SW Waterfront (WASD2) 4.9 ft (MLLW)
Alexandria (AXTV2) 3.5 ft
Anacostia (ANAD2) 3.5 ft
NAVD88 Elevation 4.0 ft
Georgetown (GTND2) 6.26 ft (WMLW)
SW Waterfront (WASD2) 5.4 ft (MLLW)
Alexandria (AXTV2) 4.0 ft
Anacostia (ANAD2) 4.0 ft
NAVD88 Elevation 4.5 ft
Georgetown (GTND2) 6.76 ft (WMLW)
SW Waterfront (WASD2) 5.9 ft (MLLW)
Alexandria (AXTV2) 4.5 ft
Anacostia (ANAD2) 4.5 ft
NAVD88 Elevation 5.0 ft
Georgetown (GTND2) 7.26 ft (WMLW)
SW Waterfront (WASD2) 6.4 ft (MLLW)
Alexandria (AXTV2) 5.0 ft
Anacostia (ANAD2) 5.0 ft
NAVD88 Elevation 5.5 ft
Georgetown (GTND2) 7.76 ft (WMLW)
SW Waterfront (WASD2) 6.9 ft (MLLW)
Alexandria (AXTV2) 5.5 ft
Anacostia (ANAD2) 5.5 ft
NAVD88 Elevation 6.0 ft
Georgetown (GTND2) 8.26 ft (WMLW)
SW Waterfront (WASD2) 7.4 ft (MLLW)
Alexandria (AXTV2) 6.0 ft
Anacostia (ANAD2) 6.0 ft
NAVD88 Elevation 6.5 ft
Georgetown (GTND2) 8.76 ft (WMLW)
SW Waterfront (WASD2) 7.9 ft (MLLW)
Alexandria (AXTV2) 6.5 ft
Anacostia (ANAD2) 6.5 ft
NAVD88 Elevation 7.0 ft
Georgetown (GTND2) 9.26 ft (WMLW)
SW Waterfront (WASD2) 8.4 ft (MLLW)
Alexandria (AXTV2) 7.0 ft
Anacostia (ANAD2) 7.0 ft
NAVD88 Elevation 8.0 ft
Georgetown (GTND2) 10.26 ft (WMLW)
SW Waterfront (WASD2) 9.4 ft (MLLW)
Alexandria (AXTV2) 8.0 ft
Anacostia (ANAD2) 8.0 ft
NAVD88 Elevation 9.0 ft
Georgetown (GTND2) 11.26 ft (WMLW)
SW Waterfront (WASD2) 10.4 ft (MLLW)
Alexandria (AXTV2) 9.0 ft
Anacostia (ANAD2) 9.0 ft
NAVD88 Elevation 10.0 ft
Georgetown (GTND2) 12.26 ft (WMLW)
SW Waterfront (WASD2) 11.4 ft (MLLW)
Alexandria (AXTV2) 10.0 ft
Anacostia (ANAD2) 10.0 ft
NAVD88 Elevation 11.0 ft
Georgetown (GTND2) 13.26 ft (WMLW)
SW Waterfront (WASD2) 12.4 ft (MLLW)
Alexandria (AXTV2) 11.0 ft
Anacostia (ANAD2) 11.0 ft
NAVD88 Elevation 12.0 ft
Georgetown (GTND2) 14.26 ft (WMLW)
SW Waterfront (WASD2) 13.4 ft (MLLW)
Alexandria (AXTV2) 12.0 ft
Anacostia (ANAD2) 12.0 ft
NAVD88 Elevation 13.0 ft
Georgetown (GTND2) 15.26 ft (WMLW)
SW Waterfront (WASD2) 14.4 ft (MLLW)
Alexandria (AXTV2) 13.0 ft
Anacostia (ANAD2) 13.0 ft
NAVD88 Elevation 14.0 ft
Georgetown (GTND2) 16.26 ft (WMLW)
SW Waterfront (WASD2) 15.4 ft (MLLW)
Alexandria (AXTV2) 14.0 ft
Anacostia (ANAD2) 14.0 ft
NAVD88 Elevation 15.0 ft
Georgetown (GTND2) 17.26 ft (WMLW)
SW Waterfront (WASD2) 16.4 ft (MLLW)
Alexandria (AXTV2) 15.0 ft
Anacostia (ANAD2) 15.0 ft
NAVD88 Elevation 16.0 ft
Georgetown (GTND2) 18.26 ft (WMLW)
SW Waterfront (WASD2) 17.4 ft (MLLW)
Alexandria (AXTV2) 16.0 ft
Anacostia (ANAD2) 16.0 ft
NAVD88 Elevation 17.0 ft
Georgetown (GTND2) 19.26 ft (WMLW)
SW Waterfront (WASD2) 18.4 ft (MLLW)
Alexandria (AXTV2) 17.0 ft
Anacostia (ANAD2) 17.0 ft

Depending on your internet connection, it could take up to one minute for the map to be drawn after you select a water level.

Select Water Level (in NAVD88):
Use the tabs above to relate this
value to local datums if needed.