Why Weather Predicting Will Never Be Perfect
Modern meteorologists use multiple computer models ingesting trillions of data points. Most of the data comes from satellites, providing information like temperature at different layers of the atmosphere. And more data is collected from land instruments. Commercial aircrafts are also able to funnel info to computer models.
Each model takes the information and produces a slightly different prediction, based on different assumptions the model is making about the weather. However, there's always going to be some unpredictability because observations can't be taken everywhere. Also, computer models are constantly being upgraded. Some say weather prediction will always be 95% science and 5% art. In other words, a bit of forecasting intuition comes into play.
And sometimes a gut feeling is the difference between a perfect forecast and something far from it.