Operational MRMS products are available in realtime from NCEP via HTTP and LDM in GRIB2 format.

MRMS data can be accessed from NCEP in two ways:

From https://mrms.ncep.noaa.gov/data/
To access data via LDM, contact NCEP Central Operations at idp-support@noaa.gov. Please use “MRMS Data Request” in your subject line. Provide your IP address and contact name, phone number and email address. NCEP Central Operations will then provide host info, LDM feed type(s), etc.