USGS AHPS Gaugeviewer app

The app is used to view USGS gaged streamflow and National Weather Service Advanced Hydrologic Prediction Service (AHPS) streamflow forecasts in the US.  The data can be downloaded in several formats, including PNG, JPEG, PDF, SVG, CSV, and WaterML. The data can also be stored in HydroShare for later access and viewing, or visualized using the CUAHSI Time Series Viewer app.

What can I do with this App?

View USGS and AHPS streamflow data

You can click on any USGS or AHPS gage in the US and view the historic streamflow data. The last two weeks of data are automatically plotted, however you can select any dates you wish to view.

Compare the streamflow to NWM forecasts

The NWM short range forecast for the nearest stream reach is automatically plotted with the USGS and AHPS streamflow data. A short, medium, or historical forecast for any stream reach can be plotted with the data to view trends and forecasts.

Download the streamflow data

The data can be downloaded in several formats including a PNG, JPEG, PDF, or SVG of the graph, a CSV file, or WaterML format.

Upload the data to HydroShare

The data can be uploaded to HydroShare where it will be saved for later use.

Example Uses of the App

  1. Click on a green USGS gage or a red AHPS gage:

    1. The two gage types can be turned on and off be clicking the checkbox on the left hand side.

  2. After clicking a gage, a pop up box will appear with basic information and hyperlinks:

    1. Click “View Data” to view a plot of the data compared to NWM forecast data, or

    2. Click “Go to Website” to go the webpage for the specific gage.

  3. After clicking the “View Data” link a series of plots will appear on a new webpage.

  4. Use the menu bar on the left side to select new ranges and forecasts:

    1. Select a new date range for the USGS Date Selection (the last two weeks are the standard range).

    2. Select a different forecast range, stream COMID, start date, or others options to view a NWM forecast.

    3. Select a new timezone to view the data according to the desired time zone.

    4. Click the “Update Graph” button to create the new graph with the desired inputs.

  5. Download the data in one of the following ways:

    1. Download an image of the graph by clicking the 3 horizontal bars just to the top right of the graph and select to download as PNG, JPEG, PDF, or SVG.

    2. Download data for use in excel by clicking the 3 horizontal bars just to the top right of the graph and select to download CSV or XLS.

    3. Download data as WaterML by clicking the “Get WaterML” button on the left hand side for the desired graph.

  6. Upload the data to HydroShare:

    1. Click the “Upload the Hydroshare” button on the left hand side.

    2. Type in any additional information and then click the “Proceed” button.

    3. After it finishes uploading, click the “HERE” button to view the data in HydroShare.

App Output

The app shows the historical forecast for the UGSS or AHPS gages and plots then against the NWM forecast. The image below shows of the standard plots that are created by the app. Notice the rise in streamflow that is forecasted after December 5th in the image below.

The data can be used in presentations, modeling, and more. The CSV file is especially helpful is you wish to manipulate the data or compare it to other streams in the region. The data can also be used in WaterML format. WaterML is a technical standard for information involving hydrologic time series structures.

Suggestions to learn more

Links to sample outputs available as Resources in HydroShare

Credits, Authors, Contributors and Contacts

The USGS and AHPS gaugeviewer App was developed at Brigham Young University and programmed using the Tethys Platform ( by Christian Kesler and the BYU Hydroinformatics lab.