For example recently Hong Kong has had 6 inches of rain in an hour. But how do they measure this as the level of water is not equal in all areas?
In: 5
It’s measured at various locations. Usually the airport and maybe some other weather stations. If the value for a larger area is reported it’ll be the average.
There are regularly placed weather station around countries. Most airports have them and if the city is large enough there could be several more. Those sation have a receptical that collect the rainfall and measures it. The measurement doesn’t take it’s reading from the ground.
Weather stations are located in various places including government buildings, airports, etc
They literally measure rainfall using a container and a ruler
People responsible take measurements and report them to the authorities
There are measuring stations.
The most basic ones are just a tube in a field. It’s sufficiently wide to account for rain that isn’t falling straight down, and sufficiently clear on all sides to prevent wind currents around buildings from manipulating the readings. The amount of rainfall is recorded from them.
In older times, they would just be manually measured after a rain storm. There’s all sorts of tooling to automate it, but the premise is the same these days — just catch the rain while controlling for variables. Do it in many locations and average it for better results.
There are phydical measuring stations. Official government ones in the us are located at airports, unofficial sources like weather underground use volunteer stations get data from stations located more broadly in cities. Weather radar can also show amounts of precipitation in the air so they can see how much water is falling over larger areas.
Commercial weather providers also aggregate their own stations and official government sources to provide information to their subscribers.
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