IMERG Early Run Example January 24th, 2020


Precipitation data from the GPM and TRMM missions are made available free to the public in a variety of formats from several sources at NASA Goddard Space Flight Center. This section outlines the different types of data available, the levels of processing, the sources to download the data, and some helpful tips for utilizing precipitation data in your research.

Beginner Resources



Data Visualization

Data FAQ

Learn about IMERG


Frequently Asked Questions

How do I get precipitation data for my specific location?

There are several sources for downloading and viewing data which allow you to subset the data to only include specific parameters and/or geographic locations. These include the GES DISCGiovanni and STORM. In Giovanni you can obtain data for a specific country, U.S. state, or watershed by using the "Show Shapes" option in the "Select Region" pane.

What happened to the TRMM Multi-satellite Precipitation Analysis (TMPA / 3B4x) data products?

The TRMM satellilte has been decommissioned and stopped collecting data in April 2015. The transition from the Tropical Rainfall Measuring Mission (TRMM) data products to the Global Precipitation Measurement (GPM) mission products has completed as of August 2019. The GPM IMERG dataset now includes TRMM-era data from June 2000 to the present, and other TRMM-era data has been reprocessed with GPM-era algorithms and is now available on the GPM FTP servers. TMPA data production ended as of December 31st, 2019 and the TRMMOpen FTP server has been shut down. Historical TMPA data is still available to download from the NASA GES DISC at:

Click here for more details on the transition from TMPA to IMERG. 

Am I allowed to use GPM data for my research?

Yes, in line with NASA's general data policy. Please refer to the GPM Data Policy for further details.

How do I give credit for using GPM data?
Where can I find detailed documentation on the precipitation algorithms?

Browse our directory of GPM & TRMM data products to locate your desired algorithm, then click on the links in the algorithm description under "Documentation". All documentation is also available at the Precipitation Processing System website

What is the spatial and temporal resolution of GPM data?

The resolution of Level 0, 1, and 2 data is determined by the footprint size and observation interval of the sensors involved.  Level 3 products are given a grid spacing that is driven by the typical footprint size of the input data sets.

For our popular multi-satellite GPM IMERG data products, the spatial resolution is 0.1° x 0.1° (or roughly 10km x 10km) with a 30 minute temporal resolution.

Visit the directory of GPM & TRMM data products for details on the resolution of each specific products.

Can I use images or videos from this site or other NASA websites?

For questions about permission for using NASA images and videos, please refer to NASA's official Media Usage Guidelines. For any additional questions please contact

Is it possible to subset GPM data?

There are several sources for downloading and viewing data which allow you to subset the data to only include specific parameters and/or geographic locations. These include the GES DISCGiovanni and STORM. In Giovanni you can obtain data for a specific country, U.S. state, or watershed by using the "Show Shapes" option in the "Select Region" pane.

What is the difference between "Near Real-time" (NRT) and "Production" / "Research" data?

GPM data products can be divided into two groups (near real-time and production) depending on how soon they are created after the satellite collects the observations. For applications such as weather, flood, and crop forecasting that need precipitation estimates as soon as possible, near real-time data products are most appropriate.  GPM near real-time (GMI & DPR) products are generally available within a few hours of observation.  For all other applications, production data products are generally the best data sets to use because additional or improved inputs are used to increase accuracy.  These other inputs are only made available several days, or in some cases, several months, after the satellite observations are taken, and the production data sets are computed after all data have arrived, making possible a more careful analysis.

For the GPM IMERG dataset, IMERG Early and Late Runs are the near real-time products, while IMERG Final Run is the research / production product. Click here to learn more about the differences between IMERG Early, Late and Final. 

The GPM Core Observatory satellite is scheduled to undergo a series of orbit boost maneuvers which will raise its altitude from 400km to 435km. These boosts are tentatively scheduled for Nov. 7 and 8, 2023. As a result of these maneuvers, the observing parameters of data collected by the GPM Microwave Imager ( GMI ) and Dual-frequency Precipitation Radar ( DPR ) instruments will change, including the footprint sizes and Earth incidence angle. The algorithms which process these data must be updated to accommodate these changes, including the Level 2 GPROF, DPR, and CORRA algorithms; the Level 3...
Commencing with the data date of Friday September 1, 2023 all GPM L3 GPROF Daily and Monthly products will be updated to the designation V07C. PPS will be making these V07C products available to the public starting on Thursday September 7, 2023. The L3 CLIM GPROF data products will also be updated on Thursday September 7, 2023. These products will commence with the data start date of Thursday June 1, 2023 and also have the designation V07C. This version update is necessary to correct the L3 gridded vertical hydrometeor profile means over the high latitude regions. This update identifies pixels...
Retrospective processing of IMERG V07 Final Run has commenced as of July 2023 using the new IMERG V07 algorithm. The TRMM and GPM eras are being processed in parallel, starting at the beginning of each dataset, with a projected end date no later than Nov. 2023. IMERG V06 and V07 are sufficiently different that users are discouraged from mixing data from the two versions. V07 Early and Late Run processing will commence after the Final Run is completed. The projected timeline for IMERG V07 processing is shown in the figure below. IMERG download links are listed on the GPM website Data Directory...
PPS has begun to generate the IMERG V07 Final data product. In the coming months, PPS will create IMERG V07 Final files for the entire period of record, which starts in June 2000. PPS will finish reprocessing Version 07 Final IMERG before starting to generate the V07 near real-time (NRT) IMERG data products. The NRT IMERG data products are IMERG Early (with 4-hour latency) and IMERG Late (with 14-hour latency). Early and Late IMERG reprocessing is currently scheduled to begin in November 2023, and it will take PPS several months to create the full period of record (June 2000 to present)...
The IMERG algorithm team has finalized the IMERG V07 algorithm for the final product. This is the one that is generated with a 3 month latency. PPS has started the reprocessing and processing of V07 IMERG final. The V07 reprocessed final files will soon be available from PPS. The algorithm team has requested that the entire TRMM/GPM era IMERG-final product be reprocessed before the near real-time (NRT) early (4 hour latency) or late (14 hour latency) products are produced at V07. This will allow them to use the final IMERG product to update ancillary files used as part of the early and late...

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