The data used to generate this site's forecast track images are in a compressed comma-separated value format that is not straightforward to use. To aid end users who wish to incorporate these data into their own dynamic maps, we convert these data into shapefiles. These shapefiles are configured to depict each model's track as a uniquely named LineString. Unlike the KML-formatted data that we produce, however, individual positions and intensity information every 12 h along each model's track are not currently included as part of the shapefiles.

The shapefiles follow the ESRI Shapefile formatting conventions. They are based on a latitude-longitude projection using the WGS84 ellipse and datum.

Shapefiles for the "early" track guidance data for the most-recent model cycle are available from the "Shapefile" option in the drop-down menu for each active storm on the website's front page. The corresponding shapefiles for the "late" and ensemble track guidance data for the most-recent model cycle, as well as archived shapefiles, are available in each storm's archive. This archive can be accessed through the "Archived Maps" entry in the drop-down menu for each active storm or from the site-wide archive linked in the navigation menu above.

You are welcome to download and import these files into ArcGIS, QGIS, or any other program or website that accepts shapefiles as input for personal use. All other uses - such as using them to drive a real-time display on your website - require approval. We typically allow such uses so long as credit is given, but please contact us with your proposed use case to learn more.