@jorisww
As an operational meteorologist, by using webcams I can see:
a) what kind of clouds exist in many locations not covered by manned meteo. stations.
b) time of rain/snow start/stop.
c) the evolution of the weather during the previous 24hrs in a certain place (to compare with the forecast I wrote down).
Also very usefull for pilots who fly in isolated airports
https://www.faa.gov/about/office_org/headquarters_offices/ato/service_units/systemops/fs/alaskan/weather_cams/
... etc ... etc ...