Severe Tropical Cyclone Bianca

[Somerset Squall]

98S has moved offshore neear Broome and developed into Tropical Cyclone Bianca, with the initial intensity being 40kts. Bianca has some very deep convection wrapping around the LLC. Bianca is moving west-southwestwards along the northern periphery of a subtropical ridge over interior Australia and will continue to do so until a trough breaks down the ridge in about 3 days time. Once this occurs, Bianca will approach the resulting weakness and head southwards. The timing of this turn is important, if it occurs sooner than forecast, places like Exmouth (or further east) could have a direct landfall from Bianca. As it stands, Bianca is forecast to be northwest of Exmouth before rounding south and impacting western and southwestern Australia as an extratropical storm.

The environment for Bianca is favourable. Shear is low, and sea temps are in excess of 30C. Therefore, Bianca will strengthen at least steadily over the next few days. The potential exists for Bianca to become intense so this cyclone will need to be closely watched. Regardless of any potential landfall, Bianca will remain fairly near the coast all the way down on the west-southwesterly track, and will bring potentially flooding rains and possible high winds from Broome right down the coast to Exmouth.

[Cookie]

Hurry Offer must end soon!

3 storms for the price of 1!

[Somerset Squall]

Thanks for posting the track may Cookie- clearly shows the risk Bianca poses to the entire Northwest Australian coast. Nice image showing all three storms too!

[Somerset Squall]

Bianca has strengthened overnight with intensity rising to 55kts. Convection remains very deep and expansive over the well defined LLC, and banding is becoming more impressive. Heavy rains look like they are lashing the coast from Port Hedland right down to Exmouth. With low shear and hot sea temperatures ahead, Bianca should continue to intensify, maybe more quickly than normal. Therefore, the cyclone needs to be closely watched.

[Cookie]

old image but nice image

[Somerset Squall]

Thanks for the image Cookie, I would agree that Bianca's satellite apperance is looking pretty impressive at the moment. Convection is deep over the centre, spiral banding flanks the storm, and an eye appears to be nearly fully formed. Intensity is now 60kts, and Bianca looks in a good position to intensify further.

EDIT: BOM has just upped the intensity to 65kts, and have declared Bianca a severe tropical cyclone.

Edited January 26, 2011 by Cridders88

[Somerset Squall]

Bianca has rapidly strengthened this eve, and is now a 90kt cat 2 on the SS scale. A little more intensification is possible for Bianca reaches colder water.

[Somerset Squall]

Bianca intensified much more than expected this morning, and the intensity shot up to 115kts, making Bianca a cat 4 on the SS scale. The severe cyclone's eye became much better defined and was embedded a strong CDO feature flanked by spiral banding. Bianca was only forecast to attain a peak intensity of 80kts, so the cyclone made very good use of it's environment. Bianca is now moving southwards, and doesn't pose any further threat to NW Australia (Bianca came close to Exmouth earlier, but stayed offshore keeping the damaging 115kt winds out to sea), but the cyclone is expected to curve southeastwards and impact Perth, SW Australia and an extratropical storm.

Bianca's movement southwards has put the cyclone over colder water and thus the intensity has already dropped to 95kts, and will continue to drop over the next day or so.

[Cookie]

A visually stunning system

Look at the Tail on her, stunning!

[Somerset Squall]

Nice imagery Cookie, and yes, that is certainly an impressive band! Bianca also attained cat 4 status quite far south. There's also a small chance Bianca will still be tropical when she makes landfall near Perth- it's not often that happens (if at all)!

[Somerset Squall]

Convection has decreased and become more shallow with Bianca as the cyclone races southeastwards towards Perth. Bianca is well on the way to becoming extratropical as sea temps have dropped below 24C and shear is high. ET transition should be complete later this evening or early tomorrow.