Subseasonal Weather Outlook and Review

Wetter conditions are predicted for much of the northern ASEAN region in the next fortnight (2 – 15 September). In Week 1 (2 – 8 September), the highest likelihood of wetter conditions is over southern Mainland Southeast Asia.

Drier conditions are predicted over the central equatorial region in Week 1 (2 – 8 September).

Warmer than usual temperature is predicted over most of the Maritime Continent in the next fortnight (2 – 15 September). Warmer than usual temperature is also predicted over northern Mainland Southeast Asia in Week 1 (2 – 8 September).

A Madden-Julian Oscillation (MJO) signal was present over the Indian Ocean (Phase 3) towards the end of August based on the RMM index. For Week 1, most models predict an MJO signal to propagate from the Maritime Continent (Phases 4 and 5) to the Western Pacific (Phases 6 and 7). For Week 2, there is disagreement between the models whether this signal will continue propagating eastwards or weaken and become indiscernible.

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.

Wetter conditions are predicted for much of the northern ASEAN region in the next fortnight (2 – 15 September). In Week 1 (2 – 8 September), the highest likelihood of wetter conditions is over southern Mainland Southeast Asia.

Drier conditions are predicted over the central equatorial region in Week 1 (2 – 8 September).

Warmer than usual temperature is predicted over most of the Maritime Continent in the next fortnight (2 – 15 September). Warmer than usual temperature is also predicted over northern Mainland Southeast Asia in Week 1 (2 – 8 September).

A Madden-Julian Oscillation (MJO) signal was present over the Indian Ocean (Phase 3) towards the end of August based on the RMM index. For Week 1, most models predict an MJO signal to propagate from the Maritime Continent (Phases 4 and 5) to the Western Pacific (Phases 6 and 7). For Week 2, there is disagreement between the models whether this signal will continue propagating eastwards or weaken and become indiscernible.

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.