The essential thing about forecasting is observation. First, I look at measurements of the things I need to predict—pressure, moisture, wind, and temperature both at the ground and thousands of feet up. I examine the satellite images that show how the clouds look from outer space. I look at the radar images, which tell me where it's raining and snowing.

I then apply my knowledge and experience about how weather works, taking into account any local variables that might affect the weather, such as closeness to the ocean or mountains. I also look at the results of special computer programs that provide me with a model of what the computer "thinks" will happen. Believe it or not, there are rules of math and physics that govern how the atmosphere works, and the computer puts it all together.

Sometimes I don't agree with the computer model's forecast, and I have to tweak it a little. That's why every bit of my own experience and knowledge helps me be as accurate as possible. Using information from the computer model combined with my own knowledge, I produce a forecast.

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