NOAA intends to negotiate a sole source purchase order with Prosensing Inc. for specialized engineering, calibration, and data validation services for the Stepped Frequency Microwave Radiometer-High Altitude (SFMR-HA) system supporting the OMAO Aircraft Operations Center. The sole source justification is based on Prosensing’s proprietary hardware ownership and specialized testing facilities, which make it the only vendor capable of performing hardware-level modifications and temperature-dependent calibration for the system. No other vendor possesses the required equipment or proprietary data to deliver validated operational calibration constants within the timelines needed for upcoming hurricane field operations. Interested firms that believe they can fully meet the requirements may submit substantiating documentation for the government to consider whether a competitive procurement is warranted. This notice is not a request for competitive proposals.