An official website of the United States government
Here’s how you know
The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.
The site is secure.
The
https://
ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.
The NOAA Climate Prediction Center (CPC) Standardized Precipitation Index (SPI) a probabilistic index derived from North American Multi-Model Ensemble (NMME) precipitation data computed f
The Global Gridded Standardized Precipitation Index (SPI) is derived from the CMORPH daily dataset and includes timescales of 1, 3, 6 and 9 months. The NOAA CMORPH precipitatio