南半球各类图像自动更新暨非扰动云团专帖（2024年7月－2025年6月）

红豆棒冰冰

AWIO20 FMEE 091115
TROPICAL CYCLONE CENTER / RSMC LA REUNION / METEO-FRANCE
BULLETIN FOR CYCLONIC ACTIVITY AND SIGNIFICANT TROPICAL WEATHER
IN THE SOUTHWEST INDIAN OCEAN
DATE: 09/05/2025 AT 1200 UTC
PART 1: WARNING SUMMARY
Nil.
PART 2 : TROPICAL WEATHER DISCUSSION
The basin features a broad Near Equatorial Trough (NET) pattern undulating around 3°S, between 56°E and 80°E.
Convective activity is confined to the slowing trade winds to the east of the Seychelles archipelago, as well as to the
north of 12°S, to the immediate east of the Mozambican coast, in the mesoscale convergences.
The weak wet phase of the MJO that will continue to cross the basin over the next few days should struggle to express
itself, being inhibited by both a near-equatorial easterly wind anomaly due to the weakly positive IOD, adding to the
current anticyclonic phase of a Rossby wave. The NET should therefore continue to lack convergence and vorticity over
the next few days, limiting cyclogenesis potential in the short term.
Development of a tropical storm is not expected over the next 5 days.
Extended outlook (D+5/D+10) :
Over the coming week, the wet phase of the MJO should shift slowly towards the Indonesian region while gradually
weakening, overlapping with a powerful equatorial Rossby wave, which should enhance vorticity near the north-eastern
border of our basin in the second part of the week (from around May 15th onwards). Some members of the EPS and
GEFS ensembles suggest the formation of a tropical low that could develop into a tropical storm in a few scenarios,
either in the Indonesian area or over the north-eastern corner of our basin. We'll thus be keeping a close eye on this
potential.