Colin Devroe

Reverse Engineer. Blogger.

Predicting the weather is no easy task

January 17, 2008

While poking around my local news station’s web site this afternoon to see how much snow we’d be getting, and when it would fall, I managed to find a thoughtful nugget left by Tom Clark – the lead Meteorologist at WNEP.

I thought I’d quote the entire thing here, because I think we can all learn something from this by parallel it to something in our lives be it at work, at home, or just about anything.

Predicting snowfall amounts is every bit as difficult as predicting rainfall amounts and in both cases the amounts can vary greatly over even short distances. However most of the time when rain is the call we are not compelled to say how much since for most of us varying amounts of rain for the most part do not matter all that much. Whether we get 3 tenths, 5 tenths or 8 tenths it doesn’t really matter. But here’s something you can take to the bank: If meteorologists had to predict how much rain would fall EVERY time rain is expected, most of the time the forecast amounts would be off by a few tenths of an inch or even more and viewers should realize this. If I said 3 tenths would fall overnight and we got 8 tenths. So what. Big deal. No complaints. Hey it rained overnight. The forecast was accurate. Yet the inaccuracy of a rainfall AMOUNT prediction pretty much goes unnoticed. In fact a lot of time we don’t even bother to predict amounts of rain yet I can guarantee to you this: that IN MOST INSTANCES the predicted amounts and the actual amounts would not match up. BUT and this is a big BUT, EVERY TIME snow is expected it becomes mandatory to predict how many inches. One inch of rain equals about ten inches of snow. That is, one inch of snow is merely a tenth of an inch of water. So if I predict 2 inches of snow and instead 7 inches falls that’s comparable to missing a rainfall forecast by 5 tenths of an inch. No big deal when it’s all rain. It’s only a little water. No one would notice. But oh my, when it’s all snow…by golly you blew it! Predict 2 inches and get 7. A total miss. Hang the weatherman. The event becomes a ‘surprise snowfall”. When newscasters and viewers sound off it can seem like we didn’t even predict a single flake. It’s so frustrating, in fact maddening. We are merely talking about a few tenths of an inch of water from the sky and unfortunately the limited accuracy of the computer guidance allows these kinds of inaccuracies to happen more often than we would like. A way around this is to categorize snowfall amounts as either nuisance, plowable or crippling. But that won’t fly. We want inches! And inches you will get but unfortunately in this day and age in between the accurate forecast of inches will come the inaccurate forecasts and with that the ridicule from those who don’t and never will appreciate and understand how difficult it is to precisly predict how much rain will fall every time it rains and how many inches will fall every time it snows.

The text is a bit rough but I wanted to leave it as is. I found it rather eye-opening (at least for me) that predicting the snow can be as hard as picking how much rain would fall down to the tenths of an inch. I knew that 1-inch of rain equalled 10-inches of snow – but never thought anything beyond that.

For me, I parallel this in many ways. One of the first is Viddler’s sign up and confirmation process. On occasion we get reports that people aren’t getting their confirmation email. Sometimes they come in, over the course of the week, in the dozens. This means that there is a larger problem underlying and we need to fix that.

I am not even sure if the two go well together but that doesn’t matter, the point is I think we can learn from the experiences of the weather man.

What does this make you think of?