AUSTIN, Texas - Weather forecasting can sometimes seem like throwing darts at a dart board.
Sometimes it's easier than that, like with Texas summers, it's a good bet that pretty much every day is going to be hot and mostly sunny. But eventually, even Texas throws in a rain forecast and that's where things get complicated. And the most powerful tools that meteorologists have are weather models.
Weather models are very complicated computer programs that can forecast either small areas or the entire globe. They work by taking in current weather data like temperature, air pressure, and humidity, and running them through several very complicated equations.
They do this for several layers in the atmosphere and after some serious computing power, kick out a forecast.
The key to an accurate forecast is using several model runs. That's because individual models are very sensitive to differences in temperature, air pressure, and humidity.
A few degrees difference can mean forecasting a hurricane or a clear sunny day. So how do meteorologists get a more accurate forecast?
We look at lots of models at the same time, and we look at models called ensemble models. Those models take several separate model runs, each with small differences in them, and compare the results.
If one model run is forecasting a huge storm, but most others are forecasting clear conditions the stormy model is probably wrong and can be ignored.
These ensemble models are very powerful when it comes to forecasting overall rainfall events and can be very accurate in predicting long-term weather trends.
The overall rainfall forecast for later this week will be most accurately predicted using an ensemble model since it "smooths out" the extremes of individual model runs.
The same can be done for forecasting drought conditions. Ensemble models are very useful in predicting how much if any, rain is forecast to fall for a certain region.
In Central Texas, the long-term ensemble models accurately predicted the drought we're experiencing today.