Weather forecastes

My understanding is that the forecasts use Monte Carlo prediction techniques. Because weather is a complex chaotic system, tiny differences in starting conditions can have huge impacts on what happens.
So they run the same model dozens of times with slightly different starting conditions. If 90% of those model runs predict rain, then they report a 90% chance of rain, and so on.

Thousands of times, probably tens of thousands of times actually.
 
I look up the report for "Merrow". Merrow is a pretty small place so it is unlikely that 10% of it would receive rain and the other 90% would not. And the BBC uses "... chance of precipitation ...". If they are talking about a percentage of an undefined area receiving precipitation, then they are using the wrong word.
They aren't reporting for Merrow, they are reporting for vast areas. In my case the area they report stretches from the Pennines to the North Sea and Durham to Whitby, so what he says makes complete sense, to me.

I use this, https://meteoradar.co.uk/expected-rainfall. It only forecasts 3 hours in advance, but it is the most accurate one I have found.
 
For the last few days the Weather forecast for today has been showing as heavy rain, rain through the night and all through the morning. Alarm set for 6.15am, pouring down, drive to the course through flooded roads and heavy rain. Park up, email from the club, course closed, day 2 of the 2 day comp cancelled! Relieved but do wish it’d been decided yesterday or even early this morning, forecasts are very rarely wrong these days.
 
The 2 weather apps I use (BBC and MetOffice) currently show little chance of rain now - around 5-7%.
A rain radar app I use shows a mahoosive band of rain tracking North from France and currently overhead..
Guess what?
It's hacking down.....
Maybe the app people need to look out of the window.....

Looks like the Met Office have opened the curtains and upgraded it to 50% chance.......:rolleyes:
So there's a 50% chance all that wet stuff is down to a flock of starlings after a heavy night out.....
 
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Based on forecast fir yesterday, you would have stayed in bed. Rain and windy.

Teed off at 9.00, played in shirtsleeves. Similar this morning.
Good job were playing the Stableford this afternoon....all the morning bunch are getting a dousing
 
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