Snow risk forecast question

[muppet]

A question about the ten day forecast on here

Eg http://www.netweather.tv/index.cgi?action=10day;sess=64c75737ac7a8d709380168361cff94b

Is the snow risk % really that or should it be multiplied by the precip risk %?

So if the precip risk is 50% and then the snow risk is 80%, is the real snow risk 50%x80%=40% ?

Thanks

[Paul]

They're effectively independent of eachother, so the prec risk is the chance of something falling from the sky and the snow risk of the chance of that being snow.

[muppet]

Thanks. Wouldn't it be clearer to then say the snow risk is 40% (using my eg) ?

Just an idea?

[Paul]

I'm not sure it would, because the risk of snow is effectively an indication of the chance of precipitation falling as snow, that doesn't change if there is a 50% or 100% risk of precipitation. If for instance we changed it to reflect the precipitation risk, you could end up with a situation where there's a 50% snow risk, and a 25% precipitation risk which would therefore mean we showed a 12.5% risk of snow. Then should there then be precipitation, the snow risk shown would be too low.

[muppet]

No problem. I just think that it would give a better indication.

I got excited when I saw snow risk was 80% but then realised it was 80% of 20%!