Code Updates

There are two series of code updates with the MRMS QPE product suite. The first set of changes come with the development products on an NSSL internal server. These products are experimental and change frequently to accommodate code changes. Only select end-users within NOAA and NASA are privy to this data. Those using development MRMS products have to accept the caveat and caution that these products are experimental, not always available, and subject to change without external notification. A list of code updates on any particular development product can be requested by contacting

The second set of changes are the official code updates at NCEP on the NCO system. This is for the operational suite of MRMS products. Listed below are the most recent significant build for the MRMS system with a summary of updates for the QPE-related products in that particular build and the plans for future builds. Information regarding past operational builds, including the large update associated with MRMS v12.0, can be found on the past update page.

MRMS v12.1.0 Update to NCO
Implementation Date: 24 February 2021

Highlights of Changes Made to the MRMS QPE Product Suite:

  • Changes to products that are available on the NWS Satellite Broadcast Network (SBN) that include the following:
    • Added to SBN (CONUS): FLASH product suite (visit the FLASH site for more information:
    • Added to SBN (Alaska and Hawaii): Composite reflectivity and precipitation product suite
    • Removed from SBN: Radar quality index (RQI), seamless hybrid scan reflectivity, probability of warm rain, and various reflectivity products
  • Ending distribution of MRMS binary-formatted products
  • Addition of Alamosa, CO radar to 2-D mosaics and improved QPE products
  • Reduced latency for Multi-Sensor QPE Pass 1 from 60 minutes to 20 minutes; Reduced latency for Multi-Sensor QPE Pass 2 from 120 minutes to 60 minutes
  • Addition of radar-only QPE accumulation since 1200 UTC product
  • Other technical and feed changes (e.g., XMRG product updates, modifications to background values, updated NetCDF and GRIB2 reference data)

MRMS v12.2.0 Update to NCO
Implementation Date: 22 April 2022

Highlights of Changes Made to the MRMS QPE Product Suite:

  • Removing the Canadian C-band (single-pol) radars and replacing them with the new S-band (dual-pol) radars
  • Updated radar quality control algorithms for the Canadian S-band radars along with updates for removal of bad data due to hardware issues, wind farm clutter mitigation, and errors with Kdp derivations
  • Improvements to bright band identifications, removal of false convective identifications, and improved QPE calculations
  • Corrected grid coordinates and gauge metadata for Hawaii domain
  • Improved gauge processing and reference data to allow for more gauges to be integrated into MRMS

More information on this build can be found through the following links:

MRMS v12.3 Update to NCO
Scheduled Implementation Date: TBD

This update will be a patch for the recently released MRMS v12.2.0. More information regarding this patch to follow soon…

MRMS v20.0 Update (and Beyond) to NCO
Scheduled Implementation Date: TBD

This update to MRMS will involve a number of scientific and coding changes, including the ability to handle radar elevation tilts below 0.5 degrees, real-time ZDR correction, sub-hourly radar QPEs, new gauge ingests, updates to precipitation estimations, etc. More information to follow…