National Drought Mitigation Center


New interactive interface and export tool help users visualize and customize U.S. Drought Monitor maps

October 24, 2022

A new interface allows users of the U.S. Drought Monitor to view Drought Monitor classifications at varous spatial scales, overlaid by other relevant information like drought outlooks, current weather, vegetation stress and recent condition reports.

For anyone who tracks drought conditions in the U.S., the brightly colored assortment of yellows, oranges and reds of the U.S. Drought Monitor map will be familiar. Users can view the country as a whole—or zoom into specific regions and states—to visualize the extent and severity of drought any given week.  

New tools from the National Drought Mitigation Center have turned the traditionally static map of the USDM into a more interactive interface where users can zoom and pan across different areas and overlay Drought Monitor data with other relevant information. They are also able to download customized USDM maps that best meet their needs and interests.  

“A common request for the USDM website is the addition of new geographic features on the map,” said Brian Fuchs, a USDM author and monitoring coordinator for the NDMC. “It was our goal to develop an interface that gives people more control over how they view and download Drought Monitor maps.” 

The new interactive interface includes both current and past USDM maps so users can view weekly drought conditions across the U.S. and its territories all the way back to 2000 when the Drought Monitor began. They can then overlay those maps with a suite of jurisdictional reference layers—including tribal lands, federal lands, crop reporting districts and political boundaries—and other sources of environmental data. 

Users can map additional layers such as precipitation and temperature forecasts and outlooks of how drought conditions may change. They can view current precipitation and streamflow data and maps of vegetation stress. They can also view the dry-to-wet condition monitoring observations submitted via the crowdsourced Condition Monitoring Observer Reports (CMOR) system and the Community Collaborative Rain, Hail and Snow (CoCoRaHS) citizen science network. Both of the latter datasets help Drought Monitor authors understand conditions on the ground and interpret complex weather data. 

“The new tools provide several novel options to give users more control over how they view the Drought Monitor,” explained Jeff Nothwehr, a GIS specialist for the NDMC. The interface, he explains, not only allows users to zoom in and out of different areas, but it also gives users easier access to a slew of climate and weather databases. “All of this valuable information from a variety of sources—the U.S. Geological Survey, the Drought Center, the National Oceanic and Atmospheric Administration and more—is now all together in one place.” 

Nothwehr adds that the new tool will also provide a broader set of options for exporting and sharing USDM data. Currently, users of the USDM can download maps for a predefined set of locations—including individual states, regions and regional climate centers—with reference data limited to major rivers and state and county borders. But a new export tool, developed in conjunction with the interactive interface, allows users to create customized versions of those maps to better meet their particular needs. With the export tool, users are able to select a unique display area and include a larger set of reference layers, such as roads, watersheds and cities. It also gives users the option of customizing map elements like the legend and title before downloading.  

The Drought Monitor is a weekly assessment of the extent and severity of drought in the U.S. and its territories. It’s released every Thursday based on various sources of data collected through the previous week. It is not a forecast, though users can now use the interactive interface to overlay current drought conditions with outlooks for the coming month and season. As of October 2022, temperature and precipitation outlooks are not mapped for Puerto Rico, and current weather data is unavailable for California and much of the Northwest over certain time periods. CoCoRaHS and CMOR observations are also only available for the previous 30 days and are an abbreviated version of the full reports.  

These new tools were developed as part of a cooperative agreement between the NDMC and the U.S. Department of Agriculture. “Our ongoing goal is to work with our partners like the USDA to find new ways to increase the accessibility and usability of the Drought Monitor,” said Fuchs. “The new interface and download tool are important steps toward that goal ensuring that we are consistently meeting the needs of USDM users.” 

Check out the new Map Viewer: 

Check out the new Map Export tool:

-- Leah Campbell, NDMC Communications