It has to be rtl_433 decoded improperly as it only shows occasionally.
grep -i unmapped /var/log/syslog
Oct 12 07:16:06 weather-new weewx[405] INFO user.sdr: unmapped:
{'dateTime': 1665555363, 'usUnits': 16, 'temperature.91.FOWH32BPacket':
20.4, 'humidity.91.FOWH32BPacket': 62.0, 'pressure.91.FOWH32BPacket':
1012.5, 'battery_ok.91.FOWH32BPacket': 0}
Oct 10 18:00:22 weather-new weewx[405] INFO user.sdr: unmapped:
{'dateTime': 1665421219, 'usUnits': 16, 'temperature.91.FOWH32BPacket':
21.8, 'humidity.91.FOWH32BPacket': 66.0, 'pressure.91.FOWH32BPacket':
1014.6, 'battery_ok.91.FOWH32BPacket': 0}