Ar there hard stats to support modern weather forecasting?

Can anyone help me out here regarding statistics on the accuracy of modern weather forecasting?

I have a friend who believes every conspiracy theory and nutbar allegation he comes across, so naturally he is convinced that 9-11 was Israelis and the CIA, and he is skeptical about everything except of course self-evident realities like the ability of gems left in the Great Pyramid overnight to cure cancer.

But I digress.

Recently he said that weather forecasters are “usually wrong” and “just guessing”.

Now, I find that hard to believe. For example, right now where I live in Canada, the temperature is an amazing 16 degrees celsius (62 Farenheit for Americans) today, April 1. All the snow has been gone for weeks and we had high temperatures during all of March. And the Weather Network, a website in Canada, predicted it all pretty much bang on. Saturday is supposed to be 24 Celsius (79 Farenheit).

All of this unusual weather was correctly predicted more than a week ago. I find it hard to believe that such accuracy could just be the result of guesswork based on average temperatures.

The problem is, Google searches for “How accurate are weather forecasts?” seem to turn up a few amateur sites of dubious scientific validity.

Now, I am sure I have heard somewhere that modern weather forecasting is 90% right about the next day, 80% about the day after, etc.

Can anybody find me a serious study or graph showing this?

here is one account