How to Use
Why Should I Use this Site?
If you live in a coastal area and are concerned about possible flooding due to extreme weather events, this site could be useful to you. The distinction made on this site is between "storm-surge" (from hurricanes) and "extra-tropical storm surge" (from non-hurricane weather systems). If a non-hurricane weather system approaches coastal areas it can still cause coastal flooding, hence the need for an "extra-tropical storm surge" forecast.
What Do the Data Mean?
The tides shown here reflect calculations of how high or low the water will be relative to a specified level. Extra-tropical "storm surge" predictions show possible change in that water height due to non-tropical weather events. Water level "observations" are the observed total water level at a station and "anomalies" are simlpy a way of showing error associated with forecasts and predictions. Total water level "predictions" are based off of predicted tides and surge and corrected using past anomalies.
Where Do the Data Come From?
Information necessary to calculate tides is provided by Center for Operational Oceanographic Products and Services (COOPS) tide stations, which may also transmit water level observations. Storm surge predictions are provided by the Meteorological Development Lab's (MDL's) Extra-tropical Storm Surge (ETSS) model. Anomalies are calculated by adding predicted tides to the storm surge forecast and subtracting that total from observed water levels (Obs - (Tide + Surge)). Future tides and surge are added together along with the average anomaly to create a total water level prediction.
How to Use this Site
Step 1: Select a Product
Decide whether a point or gridded forecast is more appropriate for your situation. Select
a geographical area for the map to focus on (lower 48 states, or the Alaska region).
Step 2: Utilize the Map
If you selected the point product, you'll have a choice of two different maps. These maps show forecast
status based on possible flood levels ('Status Map') and predicted maximum water levels with time until
occurance in hours ('Max Map'). To see a station's plot, click on a station of your choosing once the
map loads. Maps are zoomable and draggable. Once you select a station, its data will appear within
a few seconds.
The gridded option is similar; just click on one of the color-coded areas to see the dashboard for that point. Toggle between the ESTOFS and ETSS products by clicking the check boxes on the upper- right.
Step 3: Point Location Plots
The plot below shows a time series
of storm surge, water level observations, tide predictions, model anomalies, and predicted total
water level (where available). These data can be toggled on and off by clicking the labels at the
bottom of the plot and downloaded by selecting a format in the lower right hand corner. Click on
one of the datums to replot the data relative to it. Below the plot is a map which is zoomable,
draggable, and can be resized. Click on any of the orange-outlined boxes in the lower right box
to see a full size map zoomed in on that region.
A text version of the data displayed can be viewed below the maps.
Less features are available on the gridded product dashboard. Tides, site-specific datums, and water level observations are not available out at sea, making forecasts of total water level impossible. Therefore, this dashboard lacks a forecast status row. However, one can still toggle the ESTOFS and ETSS storm surge time series, select a file download type (A), and select a US region to see a full sized map (B,C) (similar to the point product dashboard).