I have a Tipping Bucket Rain Gauge and was just wondering how the Maximum
Hourly Rainfall Rate is calculated ?
The software I am using with the gauge states "Maximum Hourly Rainfall Rate,
extrapolated from highest 10 min running average during previous hour"
So for example 1mm gives a Max/Hr rate of 3.6mm

Regards

Richard

Richard Griffith wrote:
I have a Tipping Bucket Rain Gauge and was just wondering how the Maximum
Hourly Rainfall Rate is calculated ?
The software I am using with the gauge states "Maximum Hourly Rainfall Rate,
extrapolated from highest 10 min running average during previous hour"
So for example 1mm gives a Max/Hr rate of 3.6mm

I believe that on the Davis VP2 the rainfall rate is calculated by
timing successive tips of the bucket.

For example, if the bucket tips at 12:00:00 and 12:04:00 then the rain
rate is calculated as

(0.2mm / 4 ) = 0.05mm/min * 60
= 3 mm/hr

There is a max delay threshold of 15 mins (I think), which means that
the above calc is only used when there are two tips of the bucket within
15 minutes of each other.

This method of calculation does mean that if only 0.2mm (bucket size on
my VP2) of rain falls then no rain rate will be recorded, however it
could be argued that it is no worse that stating the rain rate was 0.2mm
/hr.


--
Regards,
Iain
www.stanwickweather.org.uk

I have recently installed a Young 0.1 mm TBR. It has been carefully
calibrated using a pipette. The software has been arranged so that the gauge
is sampled once per second, and the time of any tips is output to the
nearest second. The rate is calulated from 360 devided by the time between
tips. 360 = 0.1mm * 60 sec*60 min ( mm/hr). A correction factor is applied
for rates above 10 mm/hr to allow for losses during tipping, taken from the
research paper in:
Journal of Atmospheric and Oceanic Technology, V14, 6, p1512
http://ams.allenpress.com/perlserv/?...520-0426&volum
e=14


--
Bernard Burton
Wokingham, Berkshire, UK.

Satellite images at:
www.btinternet.com/~wokingham.weather/wwp.html
"Richard Griffith" wrote in message
...
I have a Tipping Bucket Rain Gauge and was just wondering how the Maximum
Hourly Rainfall Rate is calculated ?
The software I am using with the gauge states "Maximum Hourly Rainfall
Rate,
extrapolated from highest 10 min running average during previous hour"
So for example 1mm gives a Max/Hr rate of 3.6mm

Regards

Richard