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Sudden spike in "rain" "Extremes"
Posted: Mon 30 Aug 2010 9:11 pm
by wd40
Yesterday I got a sudden indication of 7" of rain in the "Extreme" section. I read all the post and I have corrected the data files so things are back to normal.
Where do these spikes come from?
Re: Sudden spike in "rain" "Extremes"
Posted: Mon 30 Aug 2010 9:26 pm
by bruce45
hi was keep get very strange rain readings and then a while ago saw the reason. bloody seagull on the rain gauge flapping its wings did the listed mod by mounting it on a solid base with plenty drain holes and sofar not had a problem.
Re: Sudden spike in "rain" "Extremes"
Posted: Mon 30 Aug 2010 9:43 pm
by steve
There are "physical" causes such as wind (and gulls!) which actually cause the bucket to move, and "electrical" causes where the rain counter in the sensor suddenly jumps up for no apparent reason.
Cumulus could do a better job of filtering out sudden huge jumps (because it's obvious when it's happened) but it's not straightforward as it's not just a case of ignoring the spike as it is with wind or temperature, because the resulting effect on the rain counter is (usually) permanent so needs to be taken into account in subsequent calculations. One day I'll see if I can do something about it.
Re: Sudden spike in "rain" "Extremes"
Posted: Tue 31 Aug 2010 12:29 am
by wd40
It sure could be a bird or squirrel.
A filter would be interesting Steve.