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

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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 IMERG V07 algorithm release has been delayed as the team works to address some artifacts discovered during the development process. Currently, a near-complete version of the algorithm is in the integration and testing phase at NASA's Precipitation Processing System (PPS). The IMERG team has also decided to run the Final V07 version first to obtain information that will be useful in the near real-time IMERG V07 Early and Late products. As a result, the Early and Late products will continue to process as IMERG V06 for several months after the Final shifts to Version 07. Please continue to...
On Tuesday April 18, 2023 at 12:00 UTC the GPM Flight Operations Team will be uploading a firmware update to the GPM satellite. During this time the instruments will be shut down and the spacecraft will be put into sun acquisition mode. No science data will be available until the spacecraft is commanded back into Mission Science Mode. Instruments are expected to be back to nominal operations by 20:00 UTC. It will take additional time for PPS production to ingest and verify the data before processing restart. We will provide an update when activities are complete and nominal production has...
The upgrade of GPROF and the Combined Radar-Radiometer Algorithm (CORRA) code to Version 07 as of 0 UTC on May 9, 2022, while IMERG continues at V06 until August, requires the Early and Late Runs to change slightly and be given the version number 06C. Specifically, the V07 GPROF and CORRA data must be used in V06 IMERG, and the GPCP climatological calibration has been recomputed to account for the change in CORRA. In addition, the GMI-other sensor calibrations will shift over the next month as V07 data are incorporated into the accumulation files. We expect the Early and Late time series to be...
Effective on May 9, 2022, the GPM near real-time (NRT) algorithm will convert to V07. There are substantial format changes in the combined and GPROF products for all radiometers. The 1C product has some additions to the swath information. Depending upon how you read the 1C files, you may or may not have to make changes in your programs. Please click here for the GPM V07 file specification document , where all the format changes and their meaning are described. For those using GPROF and combined products, please read the file specifications. There were no calibration changes in GMI, but SSMIS...
A mis-set error counter on the Core Observatory provoked a safe hold at 13:31:29 UTC on 23 March 2022, shutting down DPR and GMI observations. DPR and GMI were restored at 10:54 and 14:54 UTC, respectively on 24 March 2022. No data were recoverable from the outage period, although IMERG Early and Late continued to be produced (without GMI input, of course). The same will be true for the Final Run when it is produced. An outage at FNMOC prevented transmission of DMSP (SSMIS) from 15:51 UTC 23 March 23 to 00:47 UTC 24 March 2022. Gaps in the data are: F16: 14:34:07-19:29:39, F17: 14:56:24-19:46...

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