TCS047: To develop or not to develop
TCS047 is the next TCS invest of interest.
Attached is the 12Z IR image, Scatt data and surface observations available nearby:
IR Image, surface, ship, buoy reports, Scatt data and low-level AMVs for potentially developing system TCS047.
TCS047 is not very well developed or organized. Most of the surface winds above are easterly, although there are hints of southwest winds from the scatt images and a few ship reports.
Although there is some weak divergence aloft and a low level vorticity center. It’s just to the south of an upper low, and that may be causing the shear surrounding the invest. The shear is fairly weak over the invest center, but it is quite strong to the west and north.
See the attached divergence image, and vorticity/shear image:
Upper level divergence and AMVS (top) and deep shear and low-level vorticity (bottom). AMVs and analyses are valid 16Z on 22 September. The IR images are valid at 11 Z.
Of course the big question is when and if this system will develop.
The Met Office model weakens it through 00Z on the 24th and then slowly strengthens it, moving it to the northwest at about 18N 130E by 00Z on the 27th.
The ECMWF model analyzes the storm fairly well. It’s 12 hour forecast matches pretty well with the cloud pattern seen above. It develops this storm over the next few hours and begins to recurve it by around 12Z on the 26nd. By the end of the forecast period: October 02, the ECMWF has a very sheared system located to the south of Japan.
The GFS doesn’t really develop it at all past the short term. As it moves it north and west it kills it off, merging it with some other convective elements up near the Phillipeans. The 12Z run seems to be developing it a bit more actually. The convection seems a bit more organized. Is this a trend?
It seems there are some differences in the long term shear. See the 00z run here and the 12z shear/850 vorticity here. Look at the forecasts at 00Z on the 26th. The 12Z has a more organized system that is farther to the west than the 00Z run. It’s also under an area of lower shear. Perhaps this is encouraging it’s development.
The NOGAPS that never made it a disturbance it didn’t like, develops it steadily throughout the forecast period and brings it up east of the Phillipeans by 00Z on the 28th.
Taking a quick look at the upper levels in the two models as shown here implies that the 12Z forecaster has a weaker upper level jet, perhaps contributing to the weaker easterly flow.
Tags: Development, TCS047, Track