How can I correct a false temperature reading?

[hungerdunger]

For some unknown reason, my weather station recorded a temperature of 35.9°c at 4.55 this morning, when the temperature was actually around 14°c. The readings either side of this one were correct.

I can correct this reading in the July09log.txt file, but unfortunately the reading has set an all-time record. Again, I realise I can use Cumulus to amend this, but I would like to be able to find out what the previous record was so that I can input the details. Is there now any way I can find this out other than by searching through dayfile.txt ?

I'm also interested to know if anyone else has had experience of a false reading like this and whether there is any reason for it. Could it be the batteries are about to fail?

[steve]

I think these stations just produce silly values from time to time for no particular reason. Mine seems to, anyway. It could just be a corruption of the data as read over the USB interface - there are no checksums which would help eliminate most of these. Cumulus filters out really stupid values, but 35.9C is quite reasonable, so it's a bit harder in that case. Once I get Cumulus 2 to a reasonable state, I'll look at adding more intelligent filtering based on the recent readings.

The easiest way to find your real all-time record is to load dayfile.txt into Excel or similar, and sort the rows on the maximum temperature column.

[hungerdunger]

Thanks Steve.

Your reply has prompted me to send you a long-overdue donation for an excellent piece of software.