Tropical Weather Discussion

000 

abio10 pgtw 221800
msgid/genadmin/joint typhoon wrncen Pearl Harbor hi//
subj/significant tropical weather advisory for the Indian
/Ocean/221800z-231800zapr2018//
ref/a/msg/joint typhoon wrncen Pearl Harbor hi/220721zapr18//
ref/b/msg/joint typhoon wrncen Pearl Harbor hi/220751zapr18//
narr/ref a and ref b are tropical cyclone formation alerts.//
Rmks/
1. North Indian Ocean area (Malay Peninsula west to coast of Africa):
   a. Tropical cyclone summary: none.
   B. Tropical disturbance summary: none.
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 (invest 96s) previously located
near 4.6s 79.9e, is now located near 4.9s 80.3e, approximately 492
nm east-northeast of Diego Garcia. Animated multispectral satellite
imagery depicts a broad, slowly-consolidating low-level circulation
center (LLCC) with deep convective banding over the southern
semicircle wrapping into the western semicircle of the LLCC. A
220233z NOAA-18 89ghz image indicates fragmented deep convective
banding and broad shallow banding, however, a recent scatsat image
shows 25 to 30 knot winds associated with the aforementioned deep
convective banding. Upper-level analysis indicates low to moderate
(15 to 25 knots) vertical wind shear offset by near-radial outflow
and strong divergence aloft associated with a point source
positioned over the system. Additionally, SST values of 29 to 30c
are conducive for further development. Dynamic model guidance
depicts a generally south-southeastward to southward track over the
next two days with gradual strengthening. Maximum sustained surface
winds are estimated at 25 to 30 knots. Minimum sea level pressure is
estimated to be near 1005 mb. The potential for the development of a
significant tropical cyclone within the next 24 hours remains high.
See ref a (wtxs21 pgtw 220730) for further details.
      (2) the area of convection (invest 93s) previously located
near 10.1s 50.6e, is now located near 11.1s 50.6e, approximately 657
nm north-northwest of La Reunion. Animated multispectral satellite
imagery reveals a partially exposed low level circulation center
(LLCC) with the majority of the convection located in the southern
periphery. A 220252z ssmis 91ghz microwave image also depicts the
deep convection organizing to the south of the LLCC and beginning to
wrap into the center. Upper level analysis shows that the system is
located in an area of favorable (10-15 knots) vertical wind shear
with distinct poleward outflow which is aiding development.
Additionally, warm sea surface temperatures (28-29c) are supportive
of development. Global models are now in good agreement that the
system will intensify to tropical cyclone strength at approximately
tau 24 with the system passing along the eastern coastline of
Madagascar as it transits along a southward trajectory. Maximum
sustained surface winds are estimated at 25 to 30 knots. Minimum sea
level pressure is estimated to be near 1004 mb. The potential for
the development of a significant tropical cyclone within the next 24
hours remains high. See ref b (wtxs22 pgtw 220800) for further
details.
      (3) no other suspect areas.//

View All Hurricanes and Tropical Cyclones

Category 6

Welcome to Category 6. This is the collective home for Weather Underground's featured writeups by Dr. Jeff Masters (right), Bob Henson (left), Chris Burt, and other regular contributors.

Learn more about and the hurricane season in our hurricane archive.

View All Hurricanes and Tropical Cyclones

Hurricane Archive

All Atlantic Storms (1851-2018)

Named Storms for 2016

Historical Hurricane Statistics


Articles of Interest