Weather forecasting is a large subject that is far too deep to dive into and explain in any single article. Forecasters spend years learning how to best forecast and are constantly learning and adapting as science and technology changes. The scope of this article is to provide our customers with a little basic knowledge of what goes into making a forecast.
The purpose of this article is not to turn you into a forecaster, but instead to provide you with some basic information about where the forecasting data comes from and how we use that data. Understanding this can make your storm chasing experience more enjoyable.
First, there is a difference between a “forecast” and a “nowcast“.
Forecasting is the art and science of “predicting” what will happen by using numerical datasets and interpreting that data. Nowcasting is the act of looking at real-time weather information via remote sensing tools such as weather radar, weather satellite and weather stations.
For example, if someone said, “In Wichita the dew point is 64 degrees with winds from the south and a storm is firing approximately 50-miles to the northeast,” that would be a nowcast. The statement is explaining the conditions right now. But, if they were to say, “In 5 hours time, I expect the dewpoints in Wichita will increase into the mid-60s as a sharp dryline boundary moves into central Kansas and interacts with a cold front 50-miles north of Wichita which will be a focus of severe weather today,” that would be a forecast because the statement is a prediction.
Weather Data for Forecasting
Before a forecast can be made, forecasters need to obtain measurements of temperature, dew point temperature, atmospheric pressure, wind speeds and wind direction through all layers of the troposphere. The troposphere is the lowest level of the atmosphere, which is where all weather occurs.
On the next page, we’ll discuss how forecasters obtain weather measurements.