There will be an interruption in telecommunications service starting around 18 October 2023 that will halt real-time transmissions from as many as 813 of the 2000+ operational US Argo floats. This interruption amounts to as much as 21% of the global Argo array going temporarily offline. Many US Argo float providing activities will also have to be curtailed or halted until telecommunications service is restored. Work is being done to restore that service as quickly as possible, but the outage is likely to last from days to weeks. US Argo regrets and apologizes for these disruptions. We will issue another notice when we have more information about the likely service restoration date.