Seasonal Forecast for February – April 2026
Updated 30 January 2026
The Northeast Monsoon prevailed over the ASEAN region, with low-level winds blowing predominantly from the northwest or northeast, and typically persists over the ASEAN region until late March. During this period, the northern ASEAN region experiences its traditional dry season as the monsoon rainband remains south of the Equator. While showers are typical over the southern ASEAN region during its traditional wet season, this area can experience periods of drier conditions during the dry phase of the Northeast Monsoon, which typically takes place during February to late March. Around late March or early April, the prevailing low-level winds gradually weaken to become light and variable in direction as the Northeast Monsoon transitions into inter-monsoon conditions, when the showers gradually return to the northern ASEAN region.
For February 2026, above-normal rainfall is predicted for much of the northeastern Maritime Continent. For February – April 2026 the above-normal rainfall is predicted to persist, along with below-normal rainfall for much of the central Maritime Continent. La Niña conditions are predicted to weaken and then transition to ENSO-neutral in February – March 2026. La Niña events tend to bring wetter conditions to parts of Southeast Asia. Above-normal temperature is predicted for most of the Maritime Continent and northern and western Mainland Southeast Asia for FMA 2026.
With near- to below-normal rainfall predicted over the Mekong sub-region during the outlook period, further intensification of hotspots and smoke haze activities, with a risk of transboundary smoke haze occurrence, can be expected over fire-prone areas experiencing prolonged dry conditions. Over the southern ASEAN region, overall hotspot activity is expected to remain subdued. However, it could increase, with localised smoke plume occurrences, during periods of drier conditions under the dry phase of the Northeast Monsoon, especially in areas where below-normal rainfall is predicted.
The qualitative outlook is assessed for the region in general and based on the latest runs from models provided by the SEA RCC-Network LRF node. For specific updates on the national scale, the relevant ASEAN National Meteorological and Hydrological Services should be consulted.
For February 2026, above-normal rainfall is predicted for the northeastern Maritime Continent.
For February 2026, above-normal rainfall is predicted over the northeastern Maritime Continent based on the multi-model ensemble (Figure 1). Below-normal rainfall is predicted over parts of the central and western Maritime Continent. For the northeastern and central Maritime Continent regions, most of the models (more than six models, Figure 2) predict above-normal rainfall as the dominant tercile for the northeastern region and below-normal rainfall as the dominant tercile over central Borneo, while only four to six models agree on below normal rainfall over the western region. Model skill is good for predicting above-normal rainfall over the northeastern Maritime Continent and low to moderate for below-normal rainfall over the western and central Maritime Continent.
For Mainland Southeast Asia, much of the models (four to six, Figure 2) predict below-normal rainfall as the most likely tercile over parts of the central and southern region (Figure 1). Elsewhere in Mainland Southeast Asia there is little agreement between the models. Model skill is moderate to good for below-normal rainfall over southern Mainland Southeast Asia, and low for the rest of the region.
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| Figure 1: Rainfall tercile summary predictions of the multi model ensemble for February 2026 (contains modified Copernicus C3S information). | Figure 2: Number of models in agreement in the multi-model ensemble for the dominant tercile for February 2026. Where there no dominant tercile, it refers to the number of models with near-normal tercile (contains modified Copernicus C3S information). |
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| Figure 5: Average climatological rainfall’s lower tercile boundary for February based on CHIRPS (reference period: 1991-2020). | Figure 6: Average climatological rainfall’s upper tercile boundary for February based on CHIRPS (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. More outlook and verification plots, including for tercile and quintile probabilistic forecasts for rainfall, are in the “Model products and verification: NCEP, ECMWF, UK Met Office” on the SEA-RCC Network LRF Node webpages.
For FMA 2026, above-normal rainfall is predicted over the northeastern Maritime Continent and below-normal rainfall for much of the central Maritime Continent.
For FMA 2026, an increase in chance of above -normal rainfall is predicted for most of the northeastern Maritime Continent, with an increased chance of below-normal rainfall for the most of the southern half of the region, based on the multi-model ensemble (Figure 1). For above-normal rainfall, most models agree for the northeastern part of the region (more than six models). For below-normal rainfall, at least some of the models (4 – 6 models) agree for most of the region, with most models (more than six models) in agreement for the central and southeastern part of the region. Model skill is good over the northeastern Maritime Continent for predicting above-normal rainfall, and moderate for below-normal rainfall over the central Maritime Continent, and low to moderate elsewhere..
For Mainland Southeast Asia, no dominant tercile is predicted for most of the region. Model skill is moderate to good for central and southern Mainland Southeast Asia, and low for northern Mainland Southeast Asia.
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| Figure 1: Rainfall tercile summary predictions of the multi model ensemble for FMA 2026 (contains modified Copernicus C3S information). | Figure 2: Number of models in agreement in the multi-model ensemble for the dominant tercile for FMA 2026. Where there no dominant tercile, it refers to the number of models with near-normal tercile (contains modified Copernicus C3S information). |
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| Figure 5: Average climatological rainfall’s lower tercile boundary for FMA based on CHIRPS (reference period: 1991-2020). | Figure 6: Average climatological rainfall’s upper tercile boundary for FMA based on CHIRPS (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. More outlook and verification plots, including for tercile and quintile probabilistic forecasts for rainfall, are in the “Model products and verification: NCEP, ECMWF, UK Met Office” on the SEA-RCC Network LRF Node webpages.
For February 2026, above-normal temperature is predicted over most of the Maritime Continent and northern Mainland Southeast Asia.
For February 2026, above-normal temperature is predicted over most of the Maritime Continent and northern Mainland Southeast Asia, with the highest likelihood over the eastern Maritime Continent, based on the multi-model ensemble (Figure 1). Most of the models (more than six models, Figure 2) predict above-normal temperature as the most likely tercile for most of the mentioned regions. Elsewhere, no dominant tercile is predicted (Figure 1). Model skill for predicting above-normal temperature is relatively good for most of the Maritime Continent and low to moderate for Mainland Southeast Asia.
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| Figure 1: Temperature tercile summary predictions of the multi model ensemble for February 2026 (contains modified Copernicus C3S information). | Figure 2: Number of models in agreement in the multi-model ensemble for the dominant tercile for February 2026. Where there no dominant tercile, it refers to the number of models with near-normal tercile (contains modified Copernicus C3S information). |
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| Figure 5: Average climatological temperature for February 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. More outlook and verification plots, including for tercile and quintile probabilistic forecasts for temperature, are in the “Model products and verification: NCEP, ECMWF, UK Met Office” on the SEA-RCC Network LRF Node webpages.
For FMA 2026, above-normal temperature is predicted over most of the Maritime Continent and northern and western Mainland Southeast Asia.
For FMA 2026, above-normal temperature is predicted over the Maritime Continent (Figure 1). Most models (more than six models) predict above-normal temperature as the most likely tercile over this region (Figure 2). Model skill for predicting above-normal temperature is good for most of the Maritime Continent.
For Mainland Southeast Asia, above-normal temperature is predicted over the region (Figure 1), except for the central and southeastern parts where near-normal or near- to above-normal temperature is predicted. Most models agree on above-normal temperature as the most likely tercile for northern and western Mainland Southeast Asia, while elsewhere in the region some models (4 to 6 models) agree on the most likely tercile (Figure 2). Model skill is moderate to good for predicting above-normal temperature for Mainland Southeast Asia and low to moderate for predicting near-normal temperature.
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| Figure 1: Temperature tercile summary predictions of the multi model ensemble for FMA 2026 (contains modified Copernicus C3S information). | Figure 2: Number of models in agreement in the multi-model ensemble for the dominant tercile for FMA 2026. Where there no dominant tercile, it refers to the number of models with near-normal tercile (contains modified Copernicus C3S information). |
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| Figure 5: Average climatological temperature for FMA 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. More outlook and verification plots, including for tercile and quintile probabilistic forecasts for temperature, are in the “Model products and verification: NCEP, ECMWF, UK Met Office” on the SEA-RCC Network LRF Node webpages.
Frequently Asked Questions
What is a seasonal forecast?
A seasonal forecast provides forecast information about the general weather conditions at seasonal timescales up to several months ahead. Long range predictions rely on predicting components of the atmosphere and the oceans which show variations at large spatial and temporal scales. Among these key components is the sea-surface temperature – an important indicator in the El Niño Southern Oscillation (ENSO) cycle.
Example of probabilistic long range forecast using the multi-model ensemble. For areas nearby Peninsular Malaysia, the forecast is showing a probability of 50-70% of rainfall being in the below-normal (33%) tercile range. (Source: WMO LC LRF)
To account for the chaotic nature of the atmosphere, seasonal forecast adopts a probabilistic approach and the forecast weather condition is presented as an average over an extended period of time, usually with reference to climatology.
ASMC carries out monthly seasonal forecast predictions based on various seasonal model forecasts from the leading meteorological centres, supplemented by individual assessments from respective countries in South East Asia. The skillfulness of seasonal forecast relies greatly on the performance of seasonal models, which differ from one place to another and for different seasons of the year.
Receiver operating characteristic (ROC) score of UK GloSea5 seasonal hindcast for above-normal precipitation scenario for Dec – Feb (left) and May – Jul (right) over Asia region. Higher ROC score (indicated in red) means better model skill. (Source: UK Met Office)
For example, one way to assess the seasonal model skills is to examine the ROC score. From the figures above, we can see that ROC score map differs greatly from one season to another. During the period from Dec to Feb, a high ROC score region is observed mainly over the Philippines whereas during the period from May to Jul, a high ROC score region is observed over the near equatorial region such as Peninsular Malaysia and Sumatra.