Chances are gradually increasing for one or more cyclones to form out of a very large monsoonal trough spanning either sides of the equator, in the eastern Indian Ocean. With heavy rainfall already affecting Indonesia, up to 20 inches (500mm) more could fall in the region, with totals on the Andaman Islands approaching 600mm , according to the latest model projections.
Model support is solidifying for a potential cyclone in the Bay of Bengal or Andaman Sea by midweek, with the GFS being very bold on the current forecast, depicting a near Category 5 storm off the coast of Myanmar. This should be treated as a worse case scenario, and could have catastrophic consequences, but at the moment it is an outlier forecast.
In the South Indian Ocean, another cyclone could spawn near Indonesia, performing a hairpin turn just off the coast of Sumatra and turning back out to sea, possibly reaching hurricane equivalent status.
The GFS is also depicting a third system in the southwest Indian Ocean, but no other models support it so far and there is a lack of run consistency, and so it has not been marked for potential development.
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