I have a sensor that is powershell script that returns temperature by parsing web page of some meteostation on a public internet.

It sometimes returns a bad high value like "0" or "255" and all other values in the last days are from -17 to -4

So do enter spike filtering with maximum -4 and minimum 20 and wait. It never filters out the spikes, they are still there and the system has hardly 20 sensors (at 1 minute intervals) on i7 machine, so it cant take long to process them.

filtering powershell spike