What Does 'A 50% Chance of Rain' Actually Mean?

Your friendly local weather person says there's a 10% chance it will rain today, so you throw on your flip-flops and head out to enjoy a beautiful day. Next thing you know, you're running through puddles, trying to get out of a torrential downpour. Bad luck or bad weather person?

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[d_wang]

It means it's gonna rain if you have something important to do. And stay sunny if you don't have to do anything

[secondsuccess]

You should tell this to the cows. Apparently, whenever it's supposed to rain, they will all group up together and lie down in the field. Supposedly they do it to keep each _udder_ dry, but who knows.

[Master_Therion]

I still don't understand meteorologists on the TV. I've never heard them actually talk about meteors.

[iddobarzilai]

Man i allways feel like such a smart ass when i tell my friends about stuff i learned from this channel.

[PintsizeYT]

I enjoy seeing a 100% chance of rain, only to find out that it doesn't end up raining...

[josephdillard]

I always figured that a 50% chance of rain meant that there was just as good a chance of rain as there is no rain and so it's basically just like saying "we have no idea if it's going to rain or not"

[cup_check_official]

50% chance of rain ? how do i get this ability? is it a passive ability?

[Godsknight]

THE Meteorologist IN MY AREA IS NOT THAT CONFINDENT HE'S ALWAYS CHANGING HIS MIND

[februerin]

So this is slightly different than I had it explained to me once by a local meteorologist.
They told me the way it was calculated (estimated, really) was more like this:
X% chance of rain was based on the number of times it rained in circumstances nearly identical to the current ones, whatever they may be.
For instance, if they say it’s a 60% chance of rain, it means that in the past when the weather was recorded, when circumstances (temperature, humidity, fronts, etc.) were similar to the current ones, it rained 60% of the time, so there is a 60% chance that it might rain now, as these circumstances are similar to those past ones.
Not sure if this is even right, but it makes sense to me.

[brianxx]

The "short straw" comment betrays an anti-rain bias. Some of us like rain.

[ixamraxi]

I always assumed it meant approximations in land mass area, so 50% meant about half the region the meteorologist covers was expected to receive rain. Seems I was not too far off, though I had no idea that confidence level was a factor in the calculation. Interesting to know!

[michaelpadovani]

Perfect! Great job. Meteorologist here.

[hellojello]

One time I checked the weather forecast. It said 0% chance of rain at that time. Meanwhile, it was raining out.

A week ago it happened again! On a related note, I should find a better forcast service.

[nobodyuknow]

"What Does "A 50% Chance of Rain" Actually Mean?"
Well it's a determination made by the Bullshitometer...

[kennymartin]

Oh goody, one of the variables in the equation is completely subjective... And this is why I trust my window as my weather forecast.

[Laura-qpiw]

Thanks for explaining, I've always wondered about that

[thekatsup]

"The short straw" I live in the Valley. We get ecstatic when it actually rains. We see rain in the forecast and go, "Yeah, right."

[jacobm]

This is fitting, given the fact that my house just flooded a bit yesterday after two back to back flash floods

[DiogenesNephew]

I've read multiple articles that say that PoP does not give you the chance of being rained on in your area, when that is literally exactly what it means.

[ramshambo]

It might rain or it might not. Depending on where you are. At a certain time of day. Sounds pretty useful to me.