Tropical Cyclone Bongani

[Somerset Squall]

Invest 96S has been upgraded by MeteoFrance to a storm named Bongani. Bongani has not yet been upgraded by JTWC but should very soon, as the storm has good banding features and perststant deep convection over a well developed LLC. A pretty good start to the season to have two named storms in November.

Bongani is a small, compact storm over an environment of low shear, excellent poleward outflow and warm sea temps. As such, Bongani has the potential to rapidly intensify. Northern Madagascar needs to keep a really close eye on this as Bongani is expected to intially head westwards but then curve southwest towards the north coast as it start to round the periphery of the steering ridge to the south. Bongani could make landfall as an intense system so preperations need to be made even at this early stage.

[Cookie]

what a funny name :winky:

[Somerset Squall]

Bongani has strengthened to 40kts. The cyclone is heading westwards along the northern periphery of a steering ridge to the south. This should allow Bongani to pass north of Madagascar, though rains from the outer bands are likely to affect the coast. Bongani remains in warm waters with low shear, and good radial outflow. Bongani is therefore forecast to become a cat 1 on the SS scale, before shear increases in a few days time which will eventually cause weakening. It is unclear if Bongani will make landfall but there is the liklihood if shear doesn't kill the storm that is could move into the Mozambique Channel as the cylone veers southwards as it moves into a weakeness in the ridge.

[Cookie]

dosent look as good as it did.

[Somerset Squall]

Quite right Cookie, and after a peak of 45kts, Bongani has weakened to 35kts. Convection is displaced west of a partially exposed LLC. The convective area has shrunk over the last 24hrs. However, Bongani is still expected to re-intensify, though attaining cat 1 status appears unlikely. Easterly shear has contributed to the weakening, but poleward outflow is expected to improve greatly over the nxt 24-48hrs which may allow Bongani to become a 50kt storm. After which, shear will increase as Bongani enters the Mozambique Channel, initiating weakening again.

[Somerset Squall]

Land interaction with northern Madagascar and moderate shear have killed Bongani. Convection has diminshed and the LLC has opened up into a wave. As shear is expected to increase further, re-development appears unlikely.

Still, a promising start to the south Indian Ocean cyclone season 2009/10. Will it continue?

[Cookie]

thanks for the updates mate