Taking A Near 100% Chance
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You've probably heard me just say that the probability of The Weather Notebook coming up is near 100 percent. Well here it is, so I was right. Yet I still said near 100 percent, because when you're talking about the future, about forecasting anything, there has to be some element of uncertainty. Hi I'm Dave Thurlow. Of that, I'm 100 percent sure. But weather forecasters can not be sure about what kind of weather is coming up. This is why if on forecasts even all meteorological signs point toward rain and you can see the rain coming, the statement still has to say that the chance of rain is NEAR 100 percent.

I bring this up to introduce the idea of percent chance and what an important piece of information it is to you when listening to the latest forecast which may sound something like this: 'today we look for showers overspreading the area from south to north, and ending by midnight. Chance of rain is fifty percent.'

Percent chance means this: in the forecast area when the present set of weather conditions exist, they are shown to produce the forecaster result x percent of the time, in our little example that's fifty percent. Each spot in the area has a fifty-percent chance of rain. It does not mean that rain will only land on half of the forecast area. And, a fifty-percent chance of rain does not mean that forecasters are flipping a coin. You have a near 100 percent chance of finding out why if you tune in tomorrow to the Weather Notebook.

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