Sinlaku: 12Z September, 12th 2008
As of 12Zm September 12th, JTWC has Sinlaku near 23.7N 123.6E. It was moving 310 degrees at 5 kts
with max sustained winds of 100 kts and gusts of 125.
IR image, upper-level AMVs and JTWC track for Typhoon Sinlaku. Valid 13Z, September 12, 2008.
The above image shows Sinlaku’s solid outflow, reasonably well defined and large eye, and slightly assymetric circulation. Dry air to Sinlaku’s west may be hindering it’s outflow to that direction. It is still under fairly low shear, although there are some 20kt shear zones in the northern edges of Sinlaku.
The forecast:
The models are still uncertain about when/if Sinlaku will recurve.
The NOGAPS model that had been the least progressive, is still mostly moving Sinlaku to the northwest. By the end of the forecast cycle, however, there is a hint of Sinlaku moving northeast. It is no longer bringing Sinlaku back down across Taiwan.
The GFS forecast brings the recurvature at T+72 hours (00Z on the 15th) and then brings a slightly weakened Sinlaku into Japan by 00Z on the 17th.
The ECMWF model, which has far been the most progressive in the recurvature, is a bit to the east and north of the GFS in it’s track across Taiwan. Then, it begins the recurvature a little bit earlier, turning it to the east by 12Z on the 14th. It then bring it across the east coast of Japan: a bit to the east of the GFS.
The Met Office Global model once again sits in between the NOGAPS camp and the EC/GFS camp. It slowly moves Sinlaku up across Taiwan and then into China, but begins the recurvature much earlier than the NOGAPS by +96 (00Z on the 16th). It then moves Sinlaku much more slowly to the northeast barely bringing Sinlaku across the China coast by +120 (00Z on the 17th).
These models seem to vary when they interact with the mid-latitude westerlies. When does the ridge to the north of Sinlaku break down? Examining how observations influence the model and its subsequent track will be of interest.