SIO: INVEST 95S

[Nancy Smar]

95S INVEST 200416 1200 10.0S 119.9E SHEM 15 1010

[Nancy Smar]

ABIO10 PGTW 170730
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE INDIAN OCEAN
/REISSUED/170730Z-171800ZAPR2020//
RMKS/
1. NORTH INDIAN OCEAN AREA (MALAY PENINSULA WEST TO COAST OF AFRICA):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY: NONE.
C. SUBTROPICAL SYSTEM SUMMARY: NONE.
2. SOUTH INDIAN OCEAN AREA (135E WEST TO COAST OF AFRICA):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY:
(1) AN AREA OF CONVECTION (INVEST 95S) HAS PERSISTED NEAR
12.0S 117.6E, APPROXIMATELY 640 NM NORTH-NORTHEAST OF LEARMONTH,
AUSTRALIA. ANIMATED MULTISPECTRAL SATELLITE IMAGERY AND A 170133Z
METOP-B 89GHZ IMAGE DEPICT AN ILL-DEFINED LOW LEVEL CIRCULATION WITH
STRONG MID-LEVEL TURNING AND SOME FORMATIVE BANDING TO THE
SOUTHEAST. INVEST 95S IS IN A FAVORABLE ENVIRONMENT FOR DEVELOPMENT
WITH GOOD POLEWARD OUTFLOW, LOW (<15 KTS) VERTICAL WIND SHEAR, AND
WARM (29-31C) SEA SURFACE TEMPERATURES. GLOBAL MODELS, SPECIFICALLY
GFS AND ECMWF, SHOW FURTHER DEVELOPMENT AS A COMPACT SYSTEM AND
INTENSIFICATION FOR THE NEXT 48-60 HOURS AS INVEST 95S CONTINUES TO
TRACK SOUTHWESTWARD. NAVGEM AND UKMET IDENTIFY A CIRCULATION THAT
DOES NOT STRENGTHEN. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED
AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE
NEAR 1009 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT
TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS LOW.
(2) NO OTHER SUSPECT AREAS.
C. SUBTROPICAL SYSTEM SUMMARY: NONE.
3. JUSTIFICATION FOR REISSUE: UPGRADED AREA IN PARA 2.B.(1) TO
LOW. //
NNNN

[Nancy Smar]

A very weak low lies well north of Western Australia, near 11S 117E. It is expected to move southwest over the weekend and remain over open waters well to the north of WA. There is a small chance this system will turn towards the south southeast on Monday and head towards the west Pilbara coast. However, it is much more likely that it will instead head in a west southwesterly direction, and remain well to the northwest of the WA mainland.

The likelihood of this system developing into a tropical cyclone increases over the weekend and early next week.


Likelihood of this system being a tropical cyclone in the Western Region on:
Saturday:Very Low
Sunday:Low
Monday:Moderate