A branch of the Near Equatorial Trench (NET) persists east of 65°E between 3°S and 6°S. Convective activity is moderate in the convergences at the southern and northern edges of the NET.
At the beginnig of this week, a Kelvin wave will propagate ahead of the wet MJO approaching from the west and should cross an equatorial Rossby wave. There is also the contribution of a mixed Rossby-gravity wave, which reinforces the signal on several occasions. In this context, one or two low-pressure circulations could emerge from the NET between the centre and east of the basin over the next 5 days.
As the wave context becomes favourable, environmental conditions are improving in the east and centre of the basin. On Friday, to the east of Diego-Garcia, low-level convergence could improve in a very humid troposphere. With the circulation still wide and hampered by easterly wind shear, the development of a tropical system is likely to take some time. As far as the models are concerned, the deterministic ones confirm this slow scenario fairly well, but the ensemblists (EPS and GEFS) see several of their members developing into moderate tropical storms fairly quickly.
The likelihood of the formation of a moderate tropical storm becomes very weak from Friday 17th October near Diego-Garcia and becomes weak from saturday 18th October.
10-day outlook :
Taking into account what has been described above, the risk of cyclogenesis will increase the following week in the center of the basin.
