I see this error since today!
Mar 29 17:00:28 Wetter-Raspi4 weewx[629] INFO user.belchertown: version 1.3
Mar 29 17:00:29 Wetter-Raspi4 weewx[629] INFO user.belchertown: New forecast file downloaded to /home/nfs/wetter/json/forecast.json
Mar 29 17:00:37 Wetter-Raspi4 weewx[629] ERROR weewx.reportengine: Caught unrecoverable exception in generator 'user.belchertown.HighchartsJsonGenerator'
Mar 29 17:00:37 Wetter-Raspi4 weewx[629] ERROR weewx.reportengine: **** day is out of range for month
Mar 29 17:00:37 Wetter-Raspi4 weewx[629] ERROR weewx.reportengine: **** Traceback (most recent call last):
Mar 29 17:00:37 Wetter-Raspi4 weewx[629] ERROR weewx.reportengine: **** File "/usr/share/weewx/weewx/reportengine.py", line 197, in run
Mar 29 17:00:37 Wetter-Raspi4 weewx[629] ERROR weewx.reportengine: **** obj.start()
Mar 29 17:00:37 Wetter-Raspi4 weewx[629] ERROR weewx.reportengine: **** File "/usr/share/weewx/weewx/reportengine.py", line 385, in start
Mar 29 17:00:37 Wetter-Raspi4 weewx[629] ERROR weewx.reportengine: **** self.run()
Mar 29 17:00:37 Wetter-Raspi4 weewx[629] ERROR weewx.reportengine: **** File "/usr/share/weewx/user/belchertown.py", line 2517, in run
Mar 29 17:00:37 Wetter-Raspi4 weewx[629] ERROR weewx.reportengine: **** minstamp, maxstamp = archiveSpanSpan(
Mar 29 17:00:37 Wetter-Raspi4 weewx[629] ERROR weewx.reportengine: **** File "/usr/share/weewx/weeutil/weeutil.py", line 341, in archiveSpanSpan
Mar 29 17:00:37 Wetter-Raspi4 weewx[629] ERROR weewx.reportengine: **** start_dt = time_dt.replace(year=year, month=month)
Mar 29 17:00:37 Wetter-Raspi4 weewx[629] ERROR weewx.reportengine: **** ValueError: day is out of range for month
Mar 29 17:00:37 Wetter-Raspi4 weewx[629] ERROR weewx.reportengine: **** Generator terminated