Weather System Follow-on

The Weather System Follow-on (WSF) program, under Program Element PE 1206422SF, is a United States Space Force initiative focused on advancing space-based environmental monitoring capabilities. The program is funded through the Air Force Research, Development, Test & Evaluation (RDT&E) appropriation and is currently in the System Development & Demonstration (SDD) phase. Its primary objectives are to address validated Department of Defense (DoD) requirements for timely and accurate weather and space environment data. These capabilities are critical for global military operations, mission planning, and warfighter safety.

SSA Environmental Monitoring (SSAEM) Project 65A038 is a non-Acquisition Category (ACAT), Class D technology demonstration supporting the international Constellation Observing System for Meteorology, Ionosphere and Climate 2 (COSMIC-2) mission. SSAEM's specific goals include the acquisition, development, and on-orbit support of space and terrestrial weather sensors in partnership with the National Oceanic and Atmospheric Administration (NOAA) and Taiwan Space Agency (TASA). The sensors Tri-Global Navigation Satellite System (Tri-GNSS) Radio Occultation System (TGRS), Ion Velocity Meter (IVM), and Radio Frequency Beacon (RFB) are designed to address three Joint Requirement Oversight Committee (JROC) Category A weather capability gaps: ionospheric density, equatorial ionospheric scintillation, and electric field measurements.

SSAEM sensors provide ionospheric and atmospheric data to improve DoD operational numerical weather prediction models and enhance warfighter navigation and communication capabilities. The project includes ongoing operational improvements through TGRS flight software uploads, upgrades to data products, and system resiliency enhancements to operate in contested space domains. The acquisition strategy relies on a sole-source contract with the University Corporation for Atmospheric Research (UCAR), leveraging their expertise in radio occultation and space weather monitoring. The contract supports post-launch calibration, validation, and on-orbit operations. The mission life has been extended due to system performance exceeding expectations.

Weather System Follow-on Microwave (WSF-M) Project 65A039 is the principal investment within the WSF program, encompassing the development of a next-generation Low Earth Orbit (LEO) microwave imaging system. Managed by Space Systems Command (SSC), WSF-M aims to deliver essential weather data such as ocean surface wind speed and direction, ice thickness, snow depth, soil moisture, and energetic charged particle environment. These data products are vital for global mission planning, tropical cyclone intensity determination, and real-time support to Air Force and Navy weather centers via the Satellite Control Network (SCN) and direct broadcast to heritage terminals.

WSF-M is an Acquisition Category IB Major Defense Acquisition Program (MDAP) consisting of two space vehicles and their associated command, control, and data dissemination infrastructure. The program leverages results from the Space-Based Environmental Monitoring (SBEM) Analysis of Alternatives (AoA) to address capability gaps validated by the JROC, including timely weather collection over oceans and enhanced space weather characterization. The acquisition strategy emphasizes streamlined processes, commercial prototyping, and partnerships with NASA and other agencies to deliver cost-effective solutions.

Within WSF-M, the Compact Ocean Wind Vector Radiometer (COWVR) technology demonstration is a cooperative mission with NASA, integrating the sensor onto the International Space Station (ISS) as part of Space Test Program Houston Mission #8 (STP-H8). COWVR addresses Weather Gap #3 (Ocean Surface Vector Winds) and Gap #8 (Tropical Cyclone Intensity) by providing on-orbit demonstration and data for operational weather models. The Energetic Charged Particle (ECP) sensor, developed by the Air Force Research Laboratory (AFRL), is integrated onto the WSF-M satellites to fulfill SBEM Weather Gap #11, supporting characterization of the LEO energetic charged particle environment and anomaly resolution.

The Weather System Follow-on program's goals are to rapidly respond to evolving operational needs, enhance system resiliency in contested space environments, and leverage commercial and international partnerships for technology innovation. The program includes activities such as technical analysis, risk reduction, prototyping, and system integration, with funding allocated for both product development and management services. These efforts collectively support the delivery of advanced environmental monitoring capabilities to the DoD and allied partners, ensuring readiness and operational effectiveness in diverse and dynamic global environments.