I was chatting in a ham radio chat channel, and I asked them about it.
Two chatters called Catphish and Fishcake responded as follows:
<catphish> according to the internets: There is a SYNOP station on 10.101MHz in Germany, it runs at 50baud, with 425Hz shift and is reversed/inverted (when received on USB).
<catphish> a weather report of some sort
<catphish> "Synop is used by ships, and shore based weather stations to report prevailing conditions and forecasts. It is RTTY that has specially coded messages which allow the display of ships and weather buoys/stations and shows weather forecasts and conditions, when used in conjunction with the appropriate software"
<fishcake> i decoded
<fishcake> CQ CQ CQ DE DDK2 DDH7 DDK9
<fishcake> FREQUENCIES 4583 KHZ 7646 KHZ 10100.8 KHZ