AVHRR products from both NOAA-18 and NOAA-19 spacecraft are showing significant navigation shifts. As this issue is investigated and depending on application, these products should be used with caution. Products exhibiting the issue are those produced in the 'legacy' CoastWatch HDF format in both Level-2 Swath and Level-3 mapped products. Filenames will contain 'n18' or 'n19', such as: 2020_175_1150_n19_wi.hdf or 2020_176_0959_n19_er.hdf. For alternative SST products for your consideration, please see https://coastwatch.noaa.gov/cw/satellite-data-products/sea-surface-temperature.html and/or contact the helpdesk for additional assistance.