"Jeremy Handscomb" wrote in message
...
Just a quick question to ask how DO you actually measure rainfall totals
during a hurricane when I imagine most of the rain is coming in
horizontally?


The rain won't be coming in horizontally, although it might appear
to be doing so. Assuming that the rain gauge is in an exposed
location and not sheltered by nearby objects then the windspeed
will have no effect whatsoever upon the rainfall total.
If we consider that the trajectory of the rain is a vector made up of
two components at right angles to one another one can see that
this must be the case. The wind blows the rain sideways for sure,
the harder it blows the more 'horizontal' the rain appears.
However the vertical component is dependent only on gravity and
raindrop size and is effectively a constant.

It is this vertical component that determines what rainfall is collected.

Col
--
Bolton, Lancashire.
160m asl.