Why is it important to track weather?

It is important so that weather can be predicted in advance. Just about everyone everyday is affected by weather, and often make decisions based on what the weather will be.

There is a financial element to this as well, with most forms of commerce in some way affected. In fact, the US's National Weather Service is located within the Department of Commerce for this reason. If weather could not be predicted, many billions of dollars would be lost each year as a result.