As neither an aviator nor a meteorologist, but a terrestrial client, I have to agree about the huge strides made in both technology and knowledge from the late '60s to now, that have led to the current accuracy in forecasting.
While the BoM were responsible for rainfall forecasts, both the BoM and the organisations I worked for had responsibility for forecasting flood flows in rivers. During major floods, there were always bets made on the magnitude and timing of the flood peak. We always worked well together, though, and there was quite a bit of cross-flow with staff.