Rainfall Rate Calculation

[mcrossley]

A question for Steve on his return I guess...

How does Cumulus calculate the rainfall rate for FO stations?

I see it goes up in 0.9mm/h 'jumps', but the size of these jumps has remained at 0.9mm/h even though I have added a 0.25x multiplier into Cumulus to compensate for my 4x larger collection area. I would have naïvely expected the resolution in rate to increase by 4x too?

[steve]

I should put this in the FAQ, I guess, as it does keep getting asked. It just uses the amount of rain that fell in the last 5 minutes (approximately) and scales this up to an hour. So one 0.3 mm tip in a 5 minute period equates to a rate of 3.6 mm/hr. So it would normally be a multiple of 3.6, but with your 0.25 multiplier, it will be a multiple of 0.9.

[mcrossley]

Thanks Steve, my bad memory, I could have sworn the multiple stayed the same