12E forms!

[senorpepr]

Tropical Depression Twelve-E Discussion Number 1

Statement as of 2:00 am PDT on September 08, 2004

latest satellite intensity estimates from TAFB and SAB were
1.5/1.5...and a 25 kt tropical depression has formed. A 0553 UTC
AMSU pass as well as a 0429 UTC SSMI pass over this system
indicated a fairly well defined middle-level center with a
low-level circulation found on the NE periphery of the deepest
convection. Infrared imagery since 0000 UTC continues to indicate
increasing organization of the convection with the low-level
circulation attempting to tuck beneath the deepest convection.

System is expected to develop into a strong tropical storm in 48
hours as the easterly shear currently over it...begins to lessen.
Only hindering factor by that time will be the proximity of the
tropical cyclone to sub 26 degree celsius sea surface temperatures
noted along the current forecast track...particularly at days 4 and
5. Ships accounts for the cooling sea surface temperatures and
levels off the intensity forecast days three and four before
weakening the system on day five. The official intensity forecast
is consistent with SHIPS through day three and is weaker thereafter
due to increasingly cooler ocean temperatures.

Track forecast calls for steady WNW motion at 10 kt as a middle
level ridge N of the system remains in place through the forecast
period. By days four and five...a weakening of the system will
likely result in a steering flow more dominated by the low-level
ridge N of the system which will force what is left of the tropical
depression due west through day five.

Forecaster holweg/Stewart

forecast positions and Max winds

initial 08/0900z 15.2n 110.6w 25 kt
12hr VT 08/1800z 15.9n 112.0w 30 kt
24hr VT 09/0600z 16.5n 114.0w 35 kt
36hr VT 09/1800z 16.8n 116.0w 45 kt
48hr VT 10/0600z 17.2n 118.2w 55 kt
72hr VT 11/0600z 17.5n 123.0w 55 kt
96hr VT 12/0600z 17.5n 129.0w 35 kt...dissipating
120hr VT 13/0600z 17.5n 135.0w 25 kt...dissipating