Making money from the rain

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I have just won £10 in the Walker's Crisps Rainy Day promotion. Each packet of crisps has a code that allows you to choose a 2km x 2km square in the UK or Republic of Ireland in which you think it will rain in a couple of days time. I won after only three entries at a crisp cost of £1.20, which seems quite a good deal.

By 8am on 22nd October there had been 314,000 entries and 36,000 winners, that's a payout rate of 11% (these numbers can be found here). At 40p a packet these are fine odds (although be aware that 18-pack multi-bags only contain 3 plays).

You are only allowed one entry a day, and the strategy choices are interesting. Up to 8am on day X you can 'bet' on day X+1, which allows the use of a better weather forecast but by then most of the squares have gone. After 8am on day X you place bets on day X+2 and so the forecast is more distant, but there are more choices.

Each day the squares chosen by competitors are initially concentrated on cities rather than where it rains on the wet and green areas of Scotland, Wales and Ireland. This suggests that people are choosing squares near where they live rather than checking the weather forecast. Since this promotion is done in collaboration with the Met Office, this is not very encouraging. I believe that checking the forecasts improves the odds over the 11% average - however my 1 out of 3 success rate is hardly enough data to claim great skill.

Roll on a nice rainy November!

Added 7pm 22nd October: Just won again. Clearly the way to beat the cuts.



Ironic that Walkers are encouraging you to bet against crisp mornings.

Yes but you could make a packet!

I've a colleague playing that- think he's one £20 this week. Advised him to go for around Fort William/Mallaig- the only area outside the big cities where the squares are heavily taken, but with the difference of that being (I'm pretty sure) the wetest part of the country. Odd that even there people go for the towns first, leaving the open ground free. Even without checking forecasts, the retrun rate on selecting in that part of the country should be pretty good- the high mountains next to the sea create ideal rain forming geography. might start buying crisps just to get the codes- don't even like them, but the return rate for anyone clued in seems too good.

My wife and I have won £110 so far so we shouldn't complain. However the competition does show how lousy the BBC Weather forecasts are two days in advance, as like probably everybody else we have checked the forecast before choosing a square, and each time choose a square where we are told it will rain.At least 50% of the time they are wrong, with sometimes the rain coming 24 hours earlier or later. Walkers have also been crafty with only allowing 3 hour time slots, they have been at least 5 occassions when it has rained on a square I have selected but I still haven't won. I suspect it's because it rained in a three hour time slot I didn't select.

I've netted myself 8 wins out 18 using the met office forecast and sticking to the mountains.

I played 5 times. The first one, I didn't check BBC weather, just chose a nearest square to my flat, so I didn't win. The other 4, I checked BBC weather everytime, even when it was x+4 days forecast, I still won. I lost one, may be because I choose the wrong time slot. I won 30 pounds from buying 5 pounds potato crisps.

I’ve won 30 pounds out of 6 predictions. The last two I didn’t win because in this latest week, everybody, seems to me, has put their predictions where BBC weather says it’s going to rain. Now you can only have a ‘good spot’ if you make the prediction between 8 AM to around 9.30 AM. After that, all the ‘good spot’ would have been taken. So, not only you have to hope that BBC weather is right, you need also to wake up early in the morning to get a ‘good spot’ for yourself. From my point of view, there’re too many serious and tough competitors these days. I decided not to play again.