Southern Hemisphere Invest Thread 2010/2011

[Somerset Squall]

South Indian Ocean:

94S has become much better organised and a tropical cyclone may be forming. Convection is persisting over a well defined LLC which is exhibiting some good banding. The invest is over warm waters and continued low shear. It looks like the silence from the southwest Indian Ocean may finally be ending.

Over the other side of the South Indian Ocean, invest 96S has formed and absorbed invest 95S. Convection is showing good rotation around a developing LLC. Although waters are a toasty 30C, shear is moderate at 20kts, which may slow further development but probably won't stop it unless it increases.

South Pacific: No invests.

Edited February 9, 2011 by Cridders88

[Somerset Squall]

South Indian Ocean:

94S became Intense Tropical Cyclone Bingiza.

96S became Tropical Cyclone 14S.

Invest 97S has formed north of Learmonth, Northwest Australia. Convection is deepening over a rapidly developing LLC. Conditions are highly favourable, with low shear, sea temps in excess of 30C and impressive dual outflow channels already established. Models are indicating some rapid intensification of 97S as it drifts southwards. JTWC have issued a tropical cyclone formation alert.

Invest 98S has formed 500 miles northeast of La Reunion. Convection is flaring to the west of an exposed LLC, buffered by moderate to high wind shear. However, favourable outflow and warm sea temps are fuelling some deep convection. Just a slight relaxation in shear could cause some rapid development as the LLC is already pretty well defined. JTWC give 98S a FAIR chance of becoming a tropical cyclone within the next 24hrs.

Invest 99S has formed near Darwin, Australia. Convection is exploding to the north of a distinct and defined LLC over Darwin. Because of this, 99S should transition into a tropical cyclone pretty much when it hits water later tonight or tomorrow, as conditions are favourable. JTWC have issued a tropical cyclone formation alert on the system.

South Pacific:

No invests.

[Somerset Squall]

South Indian Ocean:

97S became Severe Tropical Cyclone Dianne.

98S dissipated.

99S became Severe Tropical Cyclone Carlos.

Invest 91S has formed north of Derby, Australia. Flaring convection is showing signs of rotation as the disturbance tracks over water. Further development depends on whether 91S remains over water, as a southwesterly or south-southwesterly motion is expected so it's touch and go whether this occurs. BOM are quite keen to make this one a tropical cyclone later down the line IF it remains over water, and then it may only become a tropical cyclone briefly before making landfall on the Pilbarra coast.

South Pacific:

Invest 92P has formed in the Gulf Of Carpentaria. Convection is expanding healthily and almost fills the entire Gulf, but currently the convection is not showing signs of strong rotation. As with all disturbances in the GOC, development usually needs to happen quickly as land is never far away. BOM aren't indicating TC formation (at least yet) and JTWC are not mentioning the system at all. It seems the system will drift south over land in a day or two so there isn't much time for development.

[Somerset Squall]

South Indian Ocean:

91S dissipated.

Invest 97S has formed just of the coast of Mozambique. A fairly well defined LLC is evident in satellite imagery, but with little convection attached to it. 97S will need to move away from the coast if it has a chance of development. Waters in the Mozambique channel are pretty warm so if this occurs then further development appears likely.

South Pacific:

92P has dissipated.

Invest 96P has formed in the central Coral Sea. Rotation is evident within a monsoon trough stretching from the Gulf Of Carpentaria to New Caledonia. Conditions appear favourable for development as waters are warm and shear is low to moderate. This development can only occur however if the low lifts out of the monsoon trough. BOM are predicting the system to become a tropical cyclone near Vanuatu as it moves eastwards and further develops. JTWC assess TC formation potential in the next 24hrs as POOR but suggest cyclone formation thereafter.

[Somerset Squall]

South Indian Ocean;

97S dissipated.

Invest 98S has formed 650 miles west of Cocos Islands. Deep convection is persisting near a developing LLC. Shear has been high over the disturbance over the last day or two, but has eased to a moderate 15-20kts now. With waters around 28C beneath the system, further development appears likely. JTWC assess the chance of TC formation from 98S as FAIR in the next 24hrs. Meteofrance seem keen into making the system a strong tropical storm too.

South Pacific:

96P has dissipated.

[Somerset Squall]

South Indian Ocean:

98S became Tropical Cyclone Cherono.

South Pacific:

Invest 99P has formed 350 miles east of Nadi, Fiji. The system appears to be developing quite quickly with convection persisting and building near a consolidating LLC. Shear is moderate, and sea temperatures are near 30C. Because of this, further development appears likely. The LLC is fairly broad at present, but if the current rate of organisation continues, 99P could become a tropical cyclone quite soon.

[Somerset Squall]

South Indian Ocean:

No invests.

South Pacific:

99P has become much better organised today and JTWC have issued a tropical cyclone formation alert on the system. Convection has expanded and is wrapping around an increasing well defined LLC. Banding features have become quite strong about the LLC. Shear is low, and is expected to remain low on the southwesterly track. Sea temps are around 29-30C. The system could become a tropical cyclone as soon as tonight.

[Cookie]

99P

looking really good.

[Somerset Squall]

South Indian Ocean:

Invest 99S has formed 500 miles north of the Cocos Islands. Convection has been flaring near a developing LLC through the day. 99S is located in an area of low shear and sea temps around 28-29C. Therefore, further development may occur over the next couple of days. JTWC assess the chances of TC development within the next 24hrs as POOR.

Invest 90S has formed north of Port Hedland, Australia. Convection is increasing near a well defined LLC. Shear is low and sea temps are around 30C. JTWC have 24hr TC development potential as POOR, but I think this system has a real shot at development over the next couple of days.

Invest 91S has formed near Darwin, Australia. Rotation of the disturbance is good, and convection is gradually building. However, land interaction is hindering development. However, if 91S finds water, it will enjoy temperatures of 31C, which would allow the system to develop fairly quickly.

South Pacific:

99P became Severe Tropical Cyclone Bune.

No invests.

[Somerset Squall]

South Indian Ocean:

99S has become less organised. Shear is increasing and although there is some deep convection still present, the LLC is weakening. Further development appears unlikely.

90S has also become less organised. Convection has decreased considerably over the weakening LLC. Shear has increased a little which could have contributed to the weakening of the small system. Futher development appears unlikely.

91S has become considerably better organised since Wednesday. Convection has exploded over the LLC since it emerged over hot water. Banding features are materialising, and the LLC is well defined. JTWC and BOM forecast 91S to become a tropical cyclone within the next 24hrs.

South Pacific:

No invests.