510 
abio10 pgtw 071800
msgid/genadmin/navmarfcstcen Pearl Harbor hi/jtwc//
subj/significant tropical weather advisory for the Indian
/Ocean/071800z-081800znov2009//
ref/a/msg/navmarfcstcen Pearl Harbor hi/070152znov2009//
ampn/ref a is a tropical cyclone formation alert.//
Rmks/
1. North Indian Ocean area (Malay Peninsula west to coast of Africa):
   a. Tropical cyclone summary: none.
   B. Tropical disturbance summary:
      (1) the area of convection previously located near 7.1n 78.2e,
is now located near 8.1n 79.1e, approximately 85 nm north-northwest
of Colombo, Sri Lanka. Over the last 12 hours, animated
multispectral imagery showed a partially-exposed low level
circulation center (LLCC) to the west of Sri Lanka, in the Gulf of
mannar. Recent animated infrared imagery indicates the LLCC is
approaching land and may be over southern India. The recent imagery
also shows waning convection with the deepest convection over land.
Though the LLCC was recently exposed and appeared to be well-
defined, the overall circulation, as indicated by the multispectral
satellite imagery and a 071256z Quikscat pass, is very broad and
monsoonal in nature. Additionally, several 071200z ship observations
within 135 to 215 nm from the system center are reporting 10- to 15-
knot winds and low sea level pressures ranging from 1004 to 1005.5
mb. Finally, recent AMSU cross sections fail to show indications of
a warm core aloft and recent microwave images, such as the 071332z
ssmis images, do not appear to depict any banding or a defined LLCC.
Maximum sustained surface winds are estimated at 15 to 20 knots.
Minimum sea level pressure is estimated to be near 1003 mb. The
potential for the development of a significant tropical cyclone
within the next 24 hours is downgraded to poor.
      (2) no other suspect areas.
2. South Indian Ocean area (135e west to coast of Africa):
   a. Tropical cyclone summary: none.
   B. Tropical disturbance summary:
      (1) the area of convection previously located near 3.7s 74.2e,
is now located near 3.0s 73.9e, approximately 275 nm north-northeast
of Diego Garcia. Animated infrared imagery shows deep, cyclonic-
turning convection continuing to persist over the low level
circulation center (LLCC). However, water vapor imagery and upper-
level analysis indicate the presence of moderate vertical wind shear
as the subtropical ridge axis has moved further poleward while the
system has remained quasi-stationary over the last 24 hours.
Additionally, the nrl solution of the 071301z Quikscat pass shows an
elongated LLCC. Nevertheless, the osi saf solution of the same
Quikscat pass continues to show a well-defined LLCC and as the
system moves southwest under the ridge axis, the vertical wind shear
should relax. Maximum sustained surface winds are estimated at 25 to
30 knots. Minimum sea level pressure is estimated to be near 1002
mb. The potential for the development of a significant tropical
cyclone within the next 24 hours remains good. See ref a (wtxs21
pgtw 070200) for further details.
      (2) no other suspect areas.//

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