Weather Forecasting – Long-term

    Published: 06-16-2009
    Views: 13,288
    Chris Strong with the National Weather Service discusses long-range forecasting.

    Chris Strong: Hi, I am Chris Strong with the National Weather Service. We've been talking about how you can forecast the weather. The next topic we're going to discuss is long-range forecasting. Looking out for the next few hours is certainly something that many of us can do just by observing the weather and what's going on in the atmosphere around us. But if we want to know what's going to be happening several days from now, we can't just choose a simple extrapolation of storms that are on the near radar and satellite imagery right now, because certainly storm system is rising and falling all the time. Hurricanes are forming, winter storms are forming; severe thunderstorm outbreaks are forming and they're also decaying over time. So we're going to need something else to understand what's going to evolve with the atmosphere as we go through the next several days. So in order to do that comes one of more revolutionary advances in forecasting; it's been going on over the past several decades. And that's computer model forecasting. All this is is basically atmospheric simulations done by computer. The first step in order to do that obviously is to get our observations. Computers work much like we do here at the forecaster level, taking in information from all around us, so we're getting information from our surface observations, the radar, satellite, the weather balloon network that we have across the globe, also from airplanes that are crossing and cutting through the atmosphere. All of this information is getting pulled in by supercomputers that are taking in vast sources of information as to what's going on with the weather all around us. Now in order to figure out how the atmosphere is going to change over time once we have a crystal-clear picture of everything that's going on in the atmosphere around us, computers can just use mathematical and physical modeling of the atmosphere in order to figure out how these storms are going to change and they're going to involve. As computers have grown, in their resources and the amount of information that they're able to process, the amount of information that we're getting on the observation of the planet is increasing all the time, and also the forecaster knowledge that continues to increase as we get better with forecasting the weather and better with meteorology. The three of those together are really working to drive forecasting ever forward and improving what we're able to accomplish with the computer models. In the forecast that we're doing now for 5 to 7 days is about as accurate as the 2 to 4 day forecast was just 20 years ago. So we're improving with that all the time and that's able to give us a much more accurate picture is to how weather is going to evolve over the next several days. But now with the explosion of the information technology all across the globe, most of us are able to access all this information straight from our computer. If you do a simple internet search of computer model forecasting, or go to weather.

    gov, or a number of other weather sites, one of the options as usually to pick on is model forecasts. You just click on model forecast or you can go to a University Meteorology Program and look at model forecasts. We're able to look at what's going on at the surface, where hurricanes, winter storms, severe thunderstorm outbreaks are going to rise and fall across the country. How these large whirlpools of air over the planet are moving and how they're going to be affecting us. We can get a good indication of not just what's going to happen over the next several hours, what's going to happen over the next several days. Now a lot of people plan ahead to make weather decisions based on what they should do over the next several days.