Dear NWP centers, The Sentinel-6 project is pleased to announce the release of the Sentinel-6 B RO NRT Levels 1b & 2 BUFR products on GTS starting Thursday, May 21, 2026. BUFR products from the first satellite, Sentinel-6 Michael Freilich (“MF”, also known as “A”), will continue to be made available on GTS. S6-B and S6-MF are currently flying in tandem with a 30-second orbital separation. As a result, the RO measurements from both satellites are closely collocated. The satellites will be in this tandem phase until S6-MF is moved to a different orbit, which will happen no earlier than October 2026 and possibly by January 2027 (TBC). We will follow-up with another announcement when S6-MF has been moved to its new orbit at which point data from both satellites will no longer be collocated. Validation The GNSS-RO instrument has been working nominally on S6-B with antenna beam-forming enabled, producing SNRs comparable to COSMIC-2 setting occultations. Rising occultations have lower SNRs than COSMIC-2 due to the smaller fore-looking RO antenna on the Sentinel-6 satellites. As of this writing, the average number of NRT BUFR products generated per day is about 1100. Comparisons with ECMWF and NCEP models of the retrieved bending angle profiles in the core region around 15-40 km show performance characteristics for both Sentinel-6 satellites that are similar to other validated GNSS-RO missions with a bias less than 0.1% in magnitude. The Sentinel-6 B BUFR products have been assessed by partner NWP centers, which include NOAA, ECMWF, UK Met Office, Météo France, DWD, ECCC, and JCSDA, and were deemed to be of sufficient quality for weather forecasting purposes. NWP partners have recommended their release on GTS for weather forecasting purposes. WMO Routing Headers The abbreviated WMO headers for the products from Sentinel-6 B are: Abbreviated WMO header Source Comments IPXB01 KWBC Sentinel-6 B BUFR product generated from NASA/JPL’s RO primary processor Frequently used IPXB02 KWBC Sentinel-6 B BUFR product generated from NASA/JPL’s RO back-up processor Rarely used BUFR products will be delivered from the primary processor unless an issue is encountered during operational processing that prevents product generation and/or distribution from the primary site. In such an event, products will be delivered from the back-up processor using the corresponding WMO routing header listed in the table above. The satellite code in the BUFR product for Sentinel-6 B is 67. Please let us know if you have any questions or encounter any issues with the new Sentinel-6 B data. Best, Chad, on behalf of the Sentinel-6 RO team [JPL logo] Chad Galley Technologist 362G | Near Earth Tracking Systems JPL 4800 Oak Grove Drive Pasadena, CA 91109 Mail Stop 238-600 M: 410.491.0024 O: 818.354.1013 F: 818.393.4965 chad.r.galley@jpl.nasa.gov<mailto:chad.r.galley@jpl.nasa.gov>
