"James Wilkinson Sword" wrote in message
news
On Thu, 20 Jul 2017 12:22:20 +0100, Ash Burton
wrote:

On 20/07/2017 12:13, James Wilkinson Sword wrote:
What do you believe weather forecasters mean when they say "40% chance
of rain"?

1) It will rain for 40% of the day.
2) There's a 40% chance it will rain at some point.

I googled it and apparently it depends on the forecaster? 1) and 2) are
completely different meanings.

I think it means 2

So pretty useless then.

Nope.

I have no idea if it will be for 20 minutes or the entire day.

You do when the forecaster has enough of a clue to have
an hourly or 3 hourly breakdown too like ours does.