Forecasting is an ever-changing process because the atmosphere is so dynamic. A meteorologist might have a hundred reasons for forecasting a certain event, but if one of those reasons is wrong, the forecast will bust.
"Think of it like a set of dominos," AccuWeather Meteorologist Bernie Rayno said. "You have one domino here, you have the 10,000th one there, and at the end is your pot of gold, that is, the correct forecast. Well, in order to get to there, every domino better be in the right spot and be lined up perfectly so everything falls to get the correct assessment."
With sophisticated computer models, forecasters can get an idea about the storms coming to the United States a week to 10 days in advance. The models' accuracy is weakened by sparse current weather data into the models.
"A lot of our storms originate out in the Pacific Ocean," AccuWeather meteorologist Mark Mancuso said. "In the Pacific Ocean, we have very little data coming from observation spots. There's a few islands out there that might send up a weather balloon. You might get a report here or there about what the profile of the atmosphere is like but a lot of the forecasting done with our models initially is an estimation using satellite data.
[There is] a lot of estimation and very little [actual] data. Once the systems get on land, you get a lot more data and then the models, they can do a lot better job on the forecast. You can get a lot of timing differences, intensity differences, with these storm systems."
If you put garbage into the models, you get a garbage forecast out. Forecasting is more than just interpreting models. It is an understanding of the atmosphere in the language of physics and mathematics.
"I think sometimes as meteorologists, since we have the models that do all the math and physics for us, you lose sight of that and we tend to trust them too much," Rayno said. "I believe a lot of the busted forecasts that we see, I saw 70-80% is because we are buying the models lock, stock and barrel and forgetting the meteorology."