Tropical Cyclone Irina

[Somerset Squall]

Invest 92S has become Tropical Cyclone Irina over northern Madagascar, with an intensity of 35kts. Irina will not strengthen any further until it moves out into the Mozambique Channel (this part of the basin as been very active this year!). Conditions are favourable here with warm waters, low shear and favourable upper level outflow. Irina could rapidly intensify as the channel is known to support rapid development, prime example being TC Funso last month. Definitely one to watch.

[Konstantinos]

http://tropic.ssec.wisc.edu/real-time/storm.php?&basin=indian&sname=92S&zoom=4&img=1&vars=11111000000000000000&loop=0

[Somerset Squall]

Irina weakened over land but is now re-organising in the northern Mozambique Channel. Moderate shear has negatively impacted the system, and along with the land interaction, has brought Irina below TC strength. Ex-Irina looks close to becoming a TC again however, as convection is building closer to the LLC now that the shear is easing. This reduction in shear and the warm waters in the channel should support intensification over the next few days as Irina moves southwestwards towards the coast of Mozambique.

[Somerset Squall]

Irina strengthened significantly as it moved into the channel and reached a 60kt intensity. Irina has moved south along the western periphery of a subtropical ridge east of Madagascar. This has brought the cyclone very close to the west coast and land interaction has weakened Irina to 55kts. The convection has reduced a lot over the last 6hrs in particular, though a small area of rather intense convection remains centrally over the LLC. The steering ridge is expected to re-orientate south of Irina over the next couple of days, forcing Irina west. As Irina moves away from land, the cyclone should strengthen again in low shear and warm sea temperatures. The westward track is forecast to persist, meaning a landfall on the Mozambique is likely in around 3-4 days time.

[Konstantinos]

[Somerset Squall]

Irina has weakened considerably as it moves westwards across the Mozambique Channel. Dry air has impacted the cyclone, along with moderate northwesterly shear. Intensity has fallen to 35kts. Conditions are expected to be marginally favourable for some modest intensification over the next few days, but dry air and moderate shear are expected to persist, capping any significant intensity gains. The track forecast is uncertain. Irina is slowing as steering currents collapse. Irina is expected to loop and meander off the coast of Mozambique near Maputo, and could make landfall in about 3 days time though the timing and the actuality of the landfall happening is open to question.

[Somerset Squall]

Irina Has restrengthened to 50kts as it has very slowly retreated southeastwards away from the Mozambique coast. However, Irina is expected to complete its very slow counter clockwise loop and move over waters upwelled by the cyclone a few days ago, which will lead to weakening before landfall near Maputo, Mozambique. The timing of this is uncertain still, due to the erratic and weak steering environment.

[Somerset Squall]

Irina has began to weaken again. The track forecast has also changed, with Irina likely to drift north from it's current position but now dissipate over the open waters of the southern Mozambique Channel. Dry/stable air is likely the cause of the current weakening.

Edited March 6, 2012 by Somerset Squall

[Somerset Squall]

Irina has killed 65 people in Madagascar, according to latest reports:

http://news.discovery.com/earth/madagascar-cyclone-irina-120306.html

After weakening to 35kts last night, Irina appears to be trying to make a comeback this morning. Intensity has increased to 45kts and convection is increasing near the partially exposed but well defined LLC. Irina is drifting towards the north very slowly in slack steering currents. Dry and stable air is forecasted to dissipate Irina, but based on the current convective trend, just when is open to question.

[matty40s]

This must be one of the longest cycle storms I have heard of, it keeps trundling around the channel.

What is the record life of a trpical storm??

[Somerset Squall]

Irina is a long lived storm but the record is held by Hurricane John of 1994, which occupied the East, Central and West Pacific basins through it's lifetime. John was alive from August 11th 1994 to September 10th 1994.

http://en.wikipedia.org/wiki/Hurricane_John_%281994%29

[Somerset Squall]

Irina remains a tightly organised TC with persistant but shallow convection. JTWC insist on dissipating Irina but MeteoFrance hold onto the system as it continues to track northwestwards. If Irina survives the current dry air it is likely to be pulled northwestwards into Mozambique (thus completimg the very slow loop!). Meteofrance then forecast Irina to move eastwards back out into the Mozambuque channel in 5 days time, where re-intensification could occur. It will be interesting to see what happens!

[Somerset Squall]

Irina has been downgraded to a remnant low southeast of Mozambique. A few cells of convection are bursting southeast of the fully exposed LLC, but moderate to high shear is forecast to persist making regeneration unlikely.