Creating forecasts for months and years ahead

From forecasting whether the coming season and years will be warmer or drier than normal to predicting what the world will be like in 100 years, our scientists use the same process used to produce weather forecasts hours or days ahead.

These long-range forecasts incorporate more of a global view to look out a month or more into the future. They factor in details such as the current average state of the atmosphere and the ocean at distances often thousands of miles away from the specific location of interest. Long-range forecasts estimate only the average weather, not specific weather events. Therefore, in these forecasts, language such as 'warmer than normal' and 'wetter than normal' is common.