North-east Brazil rainfall

The wet season is between February and May with considerable year-to-year and decade-to-decade variability. The forecasts are produced using a combination of dynamical forecast models and statistical predictions and include predictions of the most likely of five rainfall categories (very wet, wet, average, dry or very dry). Each of these categories has occurred in one-fifth of past years. A long-lead forecast is normally issued in December and an updated forecast is issued in February for March to May.


  • Long-range forecasts are unlike weather forecasts for the next few days.
  • Forecasts show the likelihood of a range of possible outcomes.
  • The most likely outcome in the forecast will not always happen.
  • Forecasts are for average conditions over a wide region and time period.
  • For more details on interpretation, see How to use our long-range predictions.


Our updated forecast for the March-May 2021 season favours below average rainfall in the east and above average rainfall in the west of the region. For detailed information, see our updated forecast for the 2021 season.