Monitoring Tools

U.S. Drought Monitor

The U.S. Drought Monitor is a weekly assessment of the extent and severity of drought in the United States.

Handbook of Drought Indicators and Indices

For a list of the pros and cons of 50 different drought indicators in use around the world, please refer to the Handbook of Drought Indicators and Indices. It was developed by Mark Svoboda and Brian Fuchs of the National Drought Mitigation Center at the University of Nebraska-Lincoln, and published in 2016 by the World Meteorological Organization and the Global Water Partnership. A PDF version is also available.

Drought Risk Atlas

The Drought Risk Atlas provides a historic look at drought for a specific location, going back as far as we have good data. See or download precipitation, temperature, or several different drought indices, including the U.S. Drought Monitor, the Standardized Precipitation Index and the Palmer Drought Severity Index.

Vegetation Drought Response Index

The Vegetation Drought Response Index combines data from satellites with ground-based measurements and other information to detect drought’s effects on vegetation.

Groundwater and Soil Moisture Conditions from GRACE Data Assimilation

NASA’s GRACE satellite mission provides data on how much water is beneath the Earth’s surface. We use it to map soil moisture, root zone moisture and groundwater.

Standardized Precipitation Index

• Download the program to compute the SPI with your data
• Learn about the SPI
• View archived SPI by climate division maps

The SPI tells you whether an area is dry or wet based on its historic record, and can be computed for different time intervals.