If the weather man says "it's a 50% chance of rain" does that mean he has no idea if its going to rain or not?

Answer 1

Right. It seems that sometimes they must pick people off the street to be "Weatherman of the Day'" when the real weathermen call in sick. You're better off just going outside and looking up at the sky sometimes!

Answer 2

No, it means there's a 50% chance of *measurable precipitation* on the ground. Which is much higher than a 20% chance.

Microclimates affect the weather greatly -- it may rain 1" in an hour at one spot, and not rain at all 2 miles away in a mountain shadow. Since the forecasts are usually for very large areas, they're expressed as percentage chances, which average the chances for small areas over large ones. A 50% chance of rain really means that half of the area in the forecast will get measurable precipitation, not that it's 50-50 whether it will rain or not.
:)

Answer 3

What it means is -- for the forecast area, there is a 50% chance of rain occurring somewhere within that forecast area during the forecast time frame.

Not half the area, as one reply states. Could be any portion of the forecast area, or not at all.

A 50% chance suggests that one or more variables are present in the atmosphere, which make it possible for precipitation to occur -- but only with the introduction of another variable or a change in an existing one (or more.)

Answer 4

Weather forecasts should be outlawed. They are an insult to our intelligence. The 50% chance of rain is a good example, but lately, I've heard even more ridiculous ones like, "A chance of isolated showers..." What the heck does that mean? It might rain in some places and in some places it might not? That is pretty much the biggest waste of words I've ever heard. And I wish I had the 5 minutes of my life that it took to watch the weather report back, so I could do something productive like gouge out my eyes...

Answer 5

It means that in the historical records of weather for the area, and in the computer models that are used by most meteorological services; the conditions that exist now produced rain 50% of the time.
Sometimes these sources produce a greater likelihood of rain, sometimes less.
For that day's conditions, the weather man has no solid predictors either way.
Hope this helps

Answer 6

Given the same conditions, 50 times out of 100 there will be rain.
Nothing is absolute in the atmosphere, you can't really just say "it will rain" or "it will not rain." This is a statistical forecast, which is the best you can hope for.

Answer 7

Generally Forecast are produced by computer modeling .
A computer puts in all the data and puts several(if not many)
forecasts for the different regions.
If half of the forecast models say it will rain in an area, its a 50% chance of rain and so on.
Its a best guess kind of thing.
Not an exact science.

Answer 8

Weather predictions these days are done by computers. The computers have software that looks for patterns within weatcher conditions and analyzes how often you actually get rain, or snow, or any other type of weather. Based on those patterns, the computer gives a percentage of how often that weather actually happens. That's why they say there's a chance of something happening.

Answer 9

No, it means 50% of the viewing area will experience some rain at some time that day...

Answer 10

What the weather person means is that out of the last 100 days that had these exact or at least similar conditions, it rained fifty times. He or she does not know for sure but forecasting is all about historical data.

Answer 11

Well by saying 50% chance of rain he is not going to be wrong as it might not so he has got it right or so to speak covered himself either way.