What does "RA" mean in the FAA Terminal Constraints? I'm trying to interpret the Terminal Constraints listed on the Operations Plan Advisory (https://www.fly.faa.gov/adv/adv_spt.jsp). RA seems to be used in the context of weather, but I haven't been able to find a definition for what "RA" means other than "Resolution Advisory" which I don't think is applicable in this context.

Example:

TERMINAL CONSTRAINTS:
NY METS/PHL/DC METS-RA/LOCIGS
CTL/ATL/MCO/TPA/FLL/MIA-RA/TSTMS
-RA is the METAR code for light rain.

LOCIGS is low ceilings, and TSTMS is thunderstorms.*



* Air Traffic Management Glossary of Terms (faa.gov).