Indian Ocean Tropical Weather Outlook
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abio10 pgtw 070400
msgid/genadmin/navmarfcstcen Pearl Harbor hi/jtwc//
subj/significant tropical weather advisory for the Indian Ocean
/reissued/070400z-071800znov2009//
ref/a/msg/navmarfcstcen Pearl Harbor hi/070151znov2009//
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 6.7n 77.5e,
is now located near 7.1n 78.2e, approximately 100 nm west of
Colombo, Sri Lanka. Animated infrared imagery shows a broad area of
deep convection slowly consolidating about an ill-defined low level
circulation center (LLCC). Recent scatterometer passes (061322z
Quikscat, 061534z ascat) indicate the LLCC may actually be more to
the northeast, in the vicinity of Sri Lanka. Nevertheless, the
system is located just south of the subtropical ridge axis in an
area of relatively low vertical wind shear with good upper-level
diffluence. Additionally, the environment is forecast to improve as
an approaching upper-level trough digs eastward and enhances the
poleward outflow into the mid-latitude westerlies. Maximum sustained
surface winds are estimated at 20 to 25 knots. Minimum sea level
pressure is estimated to be near 1006 mb. The potential for the
development of a significant tropical cyclone within the next 24
hours remains fair.
(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 3.2s 74.5e,
is now located near 3.7s 74.2e, approximately 245 nm north-northeast
of Diego Garcia. Animated infrared imagery shows multiple bands of
deep convection consolidating about a well-defined low level
circulation center (LLCC) which is depicted in a 062039z amsre
microwave image as well as a 061327z Quikscat pass. Upper-level
analysis indicates the system is in an area of weak steering with
moderate vertical wind shear and limited exhaust. Nevertheless, the
LLCC has strengthened over the last 12 hours and the deep convection
has persisted. Maximum sustained surface winds are estimated at 25
to 30 knots. Minimum sea level pressure is estimated to be near 1006
mb. The potential for the development of a significant tropical
cyclone within the next 24 hours is upgraded to good. See ref a
