Temperature
Seasonal Temperature Outlook: June-August 2026 (JJA)
Issued: 29 May 2026
For JJA 2026, models predict above-normal temperature over most of the ASEAN region.
For JJA 2026, above-normal temperature is predicted over most of the ASEAN region, apart from the southernmost part of the region where near- to above-normal temperature is predicted, based on the multi-model ensemble (Figure 1). Most models (more than six models) predict above-normal temperature as the most likely tercile apart from over the southernmost part where some models (four to six) agree that above-normal temperature is the most likely tercile (Figure 2). Model skill for predicting above-normal temperature is good at this time of the year.
Figure 1: Temperature tercile summary predictions of the multi model ensemble for JJA 2026 (contains modified Copernicus C3S information).
Figure 2: Number of models in agreement in the multi-model ensemble for the dominant tercile for JJA 2026. Where there is no dominant tercile, it refers to the number of models with near-normal tercile (contains modified Copernicus C3S information).
Figure 3: Average climatological temperature for JJA based on ERA5 (Reference period: 1991-2020).
The qualitative outlook is assessed for the region in general. For specific updates on the national scale, the relevant ASEAN National Meteorological and Hydrological Services should be consulted.