Tropical Storm Kulap

[Somerset Squall]

Tropical Storm Kulap has formed out of a rapidly developing disturbance located 500 miles east-southeast of Kadena AB, Japan. Intensity is currently 35kts. Ridging southeast of the system is allowing Kulap to drift northwards, but this ridging is expected to shrink away and be replaced by strong ridging to the north which will force Kulap westwards towards the Air Base. Thereafter, a continued westward track north of Taiwan and then into eastern China is expected.

Kulap is a small storm (especially compared to other West Pacific beasts) that has the potential for rapid development in the near term. Poleward outflow is excellent and is beginning to develop in the other quadrants of the storm too. Shear is low, and waters are very warm at 29C. Therefore, Kulap is expected to become a typhoon in 48hrs time, possibly sooner. JTWC mention however that Kulap is taking on annular characteristics, which may prevent continued rapid strengthening long term as the storm isolates itself from it's environment. This will be interesting to watch to see if the small storm does indeed become annular; full annularity is still quite rare for any tropical cyclone. If Kulap doesn't become fully annular, the storm may reach a peak higher than the 75kts forecast by JTWC.

Track map for Kulap:

The image above shows the small but tightly organised Kulap well south of mainland Japan.

Edited September 7, 2011 by Somerset Squall

[Somerset Squall]

Kulap has strengthened to 45kts. The track forecast has changed. Ridging southeast of Kulap is still forecast to move away from the storm. However, the ridge building to the north of Kulap was initialised too far west, and is instead forecast to build to the northeast of the storm. This will force Kulap northwestwards instead of westwards. As the track map shows above, this will mean Kulap will likely miss Kadena AB, and then re-curve northwards to northeastwards as it rounds the periphery of the ridge into the westerlies over South and North Korea. The westerlies plus cooler sea temps in the area will initiate extratropical transition in around 96hrs time.

[Somerset Squall]

Kulap has fallen apart today. A unexpected dose of high shear has stripped all the convection from the now entirely exposed LLC. An ULL is also causing subsidence over the storm. Intensity has fallen to 35kts. Kulap is not expected to recover. Track forecast remains the same, but there might not be anything to track soon.