Subseasonal Weather Outlook and Review

Drier than usual conditions are predicted over the southeastern Maritime Continent in Week 1 (13 – 19 April).

Drier than usual conditions are also predicted over much of Mainland Southeast Asia and most of the northern Maritime Continent in Week 1 (13 – 19 April). These drier conditions are predicted to ease over much of the region in Week 2 (20 – 26 April), except over southeastern Mainland Southeast Asia, the northwestern Maritime Continent, and northern Borneo where the drier conditions are likely to persist.

Warmer than usual temperatures are predicted over much of Mainland Southeast Asia and parts of the northwestern Maritime Continent in Week 1 (13 – 19 April), easing in Week 2 (20 – 26 April).

No Madden-Julian Oscillation (MJO) signal was present at the end of the first week of April 2026. Most models predict an MJO signal to develop over the Western Pacific (Phases 6 and 7) by the start of the forecast period. The MJO signal is predicted to propagate eastwards, reaching the Western Hemisphere and Africa, in Phase 8 during Week 1 (13 – 19 April) and Phase 1 during Week 2 (20 – 26 April).

The outlook is assessed for the region in general, where conditions are relative to the average conditions for the corresponding time of year. For specific updates on the national scale, the relevant ASEAN National Meteorological and Hydrological Services should be consulted.

Drier than usual conditions are predicted over the southeastern Maritime Continent in Week 1 (13 – 19 April).

Drier than usual conditions are also predicted over much of Mainland Southeast Asia and most of the northern Maritime Continent in Week 1 (13 – 19 April). These drier conditions are predicted to ease over much of the region in Week 2 (20 – 26 April), except over southeastern Mainland Southeast Asia, the northwestern Maritime Continent, and northern Borneo where the drier conditions are likely to persist.

Warmer than usual temperatures are predicted over much of Mainland Southeast Asia and parts of the northwestern Maritime Continent in Week 1 (13 – 19 April), easing in Week 2 (20 – 26 April).

No Madden-Julian Oscillation (MJO) signal was present at the end of the first week of April 2026. Most models predict an MJO signal to develop over the Western Pacific (Phases 6 and 7) by the start of the forecast period. The MJO signal is predicted to propagate eastwards, reaching the Western Hemisphere and Africa, in Phase 8 during Week 1 (13 – 19 April) and Phase 1 during Week 2 (20 – 26 April).

The outlook is assessed for the region in general, where conditions are relative to the average conditions for the corresponding time of year. For specific updates on the national scale, the relevant ASEAN National Meteorological and Hydrological Services should be consulted.