The western United States consists of complex terrain where local precipitation and temperature can vary dramatically across short distances, which in turn impact local drought conditions. The goal of WestWide Drought Tracker (WWDT) is to provide easy access to fine-scale drought monitoring and climate products that can be utilized by a variety of users. The climate data sets, drought indices, and maps that are found on WWDT use monthly data which are updated with new values at the beginning of each month using data from the PRISM Climate Mapping Program.
- Palmer Drought Severity Index (PDSI)
- Self-Calibrated Palmer Drought Severity Index (sc-PDSI)
- Palmer Z-Index
- Standardized Precipitation Index (SPI)
- Standardized Precipitation Evapotranspiration Index (SPEI)