western pacific Typhoon Kalmaegi

[Somerset Squall]

A new tropical depression has formed in the Western Pacific, well east of the Philippines. Winds are at 25kts. Convection is wrapping well on the western quadrant of the depression, although is a little thin on the northeast side. Conditions support some strengthening over the next few days, as waters are very warm and shear is low. A general west-northwesterly track is expected on the south side of ridging to the north. This puts Luzon at risk of impact from 15W in 4-5 days time, at which time JTWC expect 15W to be a 100kt typhoon. Track forecasts can change as ever, but this system is pretty concerning for the Philippines.

[Somerset Squall]

15W has slowly intensified and is now a 35kt tropical storm, named Kalmaegi. Convection has retained deep convection over the LLCC, and banding features have improved in all quadrants. Shear is moderate over Kalmaegi, but this is being offset somewhat by good upper level outflow, and very warm sea temps east of the Philippines. JTWC have backed off on the their intensity forecast prior to landfall in the Philippines, as the environment is not expected to be as favourable as first thought. Nevertheless, Kalmaegi is still expected to become a category 1 strength (SS scale) typhoon prior to landfall. There is a little disparity between when the landfall will occur between JTWC and JMA. JMA have Kalmaegi taking nearly three days to make landfall in Luzon, wheras JTWC forecast it being closer to two. This is probably due to some model disgreement about the strength of the ridge to the north. What is quite certain however, is a continution of the west-northwesterly track, which means that the landfall on Luzon is considered very likely. After clipping Luzon, Kalmaegi is expected to move across the northern South China Sea in a continued west-northwesterly motion, and make a second landfall, this time in Southern China, north of Hainan Island, as a category 2 typhoon.

 

 

[Somerset Squall]

Kalmaegi is rapidly becoming better organised. The 21:00 JTWC update put Kalmaegi's winds at 50kts, but they are probably going to be higher at the update due within the hour. The storm has developed a solid central dense overcast, with impressive spiral banding. Within the last hour or so, an eye also appears to be forming. The situation is looking far more dangerous for Luzon than it was 24hrs ago. Remember the first JTWC forecast indicating a 100kt system making landfall on Luzon? I wouldn't be surprised if that was too low an estimate. This has all the hallmarks of a monster.

 

 

 

EDIT: winds up to 55kts latest JTWC update. They are forecasting a peak of 85kts before landfall, but in my opinion, Kalmaegi could become stronger than this.

Edited September 13, 2014 by Somerset Squall

[Somerset Squall]

Kalmaegi has become a typhoon, with winds of 65kts. Further strengthening is expected before landfall in Luzon. Just how much strengthening is open to question. JTWC currently forecast winds of 85kts at landfall.

[Somerset Squall]

Kalmaegi has not strengthened as much as I thought it would, and has made landfall as a 70kt typhoon on Luzon. Kalmaegi will weaken slightly as it crosses Luzon but should recover a little before landfall on China.

[Somerset Squall]

Kalmaegi weakened to a 60kt tropical storm whilst crossing Luzon, but has now become a typhoon again, with winds of 65kts according to JTWC. Kalmaegi is reforming an eye, which is still not complete, and is rather ragged. Kalmaegi is expected to strengthen a little more before landfall on eastern Hainan/South China. This satellite image shows how large Kalmaegi is, winds are obviously of concern, but rainfall will continue to be a very serious threat over the coming days to South China and Hainan Island, and eventually northern Vietnam. Luzon still aren't out of the woods either, as the southwesterly flow around the south side of Kalmaegi brings more heavy rains here.

 

 

[Somerset Squall]

Kalmaegi peaked at 70kts for the second time before landfall. The system has now moved through Hainan Island and adjacent parts of Southern China and moved inland across northern Vietnam, where dissipation is now occuring.