Long-term forecast refers to forecasting average weather from 11 days or more to 1 year. Since the daily weather cannot be predicted, the average condition for a certain period of time is compared with the normal year in the form of higher (more) / similar / lower (less).

Long-term forecasts involve complex interactions of various climate systems, and are therefore more uncertain than short-term forecasts due to incomplete understanding. For this reason, information on the probability of occurrence is provided so that long-term forecasts can be effectively used in the decision-making process.

In the announcement, the temperature is classified by the probability for the third quartile of [higher, similar, or lower than normal] using anomaly from the normal year. Precipitation is divided into the three categories of the probability [more, similar, less than normal] using a percentile (%ile).

The 1-month outlook is released every Thursday by dividing the forecast for temperature and precipitation from the 11th day to the 4th week on a weekly basis. The 3-month outlook is released on the 23rd of each month, showing the forecast of temperature and precipitation for 3 months from next month.

The 6-month outlook is published four times a year on temperature, precipitation, and El Niño/La Niña outlook is published once a month. The 1-year Outlook is published once a year for the temperature, precipitation for the following year.