Temperature
Monthly Temperature Outlook: December 2025
Issued: 28 Nov 2025
For December 2025, above-normal temperature is predicted over most of the Maritime Continent, with below- to near-normal temperature predicted over much of central and eastern Mainland Southeast Asia.
For December 2025, above-normal temperature is predicted over most of the Maritime Continent and northwestern Mainland Southeast Asia (Figure 1). The likelihood of above-normal temperature is high over much of the eastern Maritime Continent. Most of the models (more than six models, Figure 2) predict above-normal temperature as the most likely tercile for the mentioned regions. Model skill for predicting above-normal temperature is relatively good for most of the Maritime Continent and moderate for northwestern Mainland Southeast Asia.
Elsewhere, below- to near-normal temperature is predicted over central and eastern Mainland Southeast Asia (Figure 1), with generally some models (4 – 6) in agreement with each other (Figure 2). Model skill for predicting near-to below normal temperature is low to moderate for Mainland Southeast Asia.
Figure 1: Temperature tercile summary predictions of the multi model ensemble for December 2025 (contains modified Copernicus C3S information).
Figure 2: Number of models in agreement in the multi-model ensemble for the dominant tercile for December 2025. Where there is no dominant tercile, it refers to the number of models with near-normal tercile (contains modified Copernicus C3S information).
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.