| Abbreviation | Definition |
|---|---|
| OMNI | Official Meteorological Notification Information |
| OPARS | Optimum Path Aircraft Routing System |
| OPP | Office of Polar Programs at the National Science Foundation |
| OR | Oak Ridge Operations Office |
| ORA | Office of Research and Applications |
| ORAU | Oak Ridge Association Universities |
| ORD | Operational Requirements Document |
| ORT | Office of Research and Technology Applications, NOAA |
| OSCAR | Optical Soil Canopy Atmosphere Radiance |
| OSDPD | Office of Satellite Data Processing and Distribution |
| OSF | Operational Support Facility |
| OSO | Office of Satellite Operations |
| OTIS | Optimum Thermal Interpolation System |
| OTS | Organization for Tropical Studies |
| OTSR | Optimum Track Ship Routing |
| OVC | OVerCast |
| OVCST | Overcast |
| OVG | On-demand Vortex Generator |
| OWC | Oklahoma Weather Center |
| OWS | Operational Weather Squadron |