How are computers used in weather forecasting?

We only gather this data from weather observation sites, which can be tens or hundreds of kilometers apart. To determine these values at locations between the observation sites, we interpolate. Many weather variables are important to forecasting (temperature, dew point, pressure, and wind speed, to name a few).

When forecasting, a great deal of data must be examined in order to ascertain what will happen next. If humans were to perform all of the interpolation for all of the data, they would never be able to issue the forecast in the anticipated time frame. In addition, with the complexity of values to be analyzed (such as vorticity), it is impossible for a human to determine the effect of all the various factors at play; instead, a computer must do so.

Utilizing weather radar and, to a lesser extent, satellite data does require computers as well.

Computers are used in weather forecasting through numerical weather prediction models. These models simulate the behavior of the atmosphere by solving mathematical equations that describe atmospheric processes. Computers process vast amounts of observational data from satellites, weather stations, and other sources to initialize these models. Then, they perform calculations to predict future weather conditions based on the current state of the atmosphere. This allows meteorologists to generate forecasts for various timeframes and regions, aiding in decision-making for activities such as agriculture, transportation, and disaster preparedness.