SIO: INVEST 93S

[Meow]

Southwest of Maldives.

[Crostorm]

TROPICAL DISTURBANCE SUMMARY:
(1) AN AREA OF CONVECTION HAS PERSISTED NEAR 10.4S 65.9E,
APPROXIMATELY 890 NM NORTHEAST OF LA REUNION. ANIMATED MULTISPECTRAL
SATELLITE IMAGERY DEPICTS A PARTIALLY-EXPOSED LOW-LEVEL CIRCULATION
CENTER (LLCC) WITH PERSISTENT DEEP CONVECTION SHEARED OVER THE
SOUTHERN SEMI-CIRCLE. A 070438Z ASCAT IMAGE INDICATES A BROAD
CIRCULATION WITH 20 TO 25 KNOTS WINDS OVER THE PERIPHERY. A SHIP
OBSERVATION LOCATED APPROXIMATELY 200NM SOUTH CONFIRMS THE ASCAT
DATA WITH SOUTHERLY WINDS AT 23 KNOTS. A 070957Z AMSU IMAGE SHOWS
FORMATIVE CONVECTIVE BANDING WRAPPING INTO AN ELONGATED LLCC. UPPER-
LEVEL ANALYSIS SHOWS AN IMPROVING ENVIRONMENT WITH STRONG DIFFLUENCE
AND MODERATE TO STRONG (20-30 KNOTS) VERTICAL WIND SHEAR. 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 IS LOW.

[Crostorm]

TROPICAL DISTURBANCE SUMMARY:
(1) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 10.4S
65.9E, IS NOW LOCATED NEAR 10.4S 64.3E, APPROXIMATELY 825 NM
NORTHEAST OF LA REUNION. ANIMATED INFRARED SATELLITE IMAGERY
DEPICTS A BROAD LOW-LEVEL CIRCULATION CENTER (LLCC) WITH SHALLOW
CONVECTION INHIBITED BY STRONG VERTICAL WIND SHEAR. A 070728Z OSCAT
IMAGE INDICATES A BROAD CIRCULATION ORIENTED EAST-WEST WITH 15 TO
20 KNOT WINDS NEAR THE LLCC AND 25 KNOT WINDS DISPLACED TO THE
SOUTHEAST AND NORTHEAST. THERE IS SOME EVIDENCE OF AN ADDITIONAL
CIRCULATION JUST TO THE EAST OF THIS LLCC. A BUOY OBSERVATION
LOCATED AT APPROXIMATELY 8.0S 67.0E SUPPORTS THE OSCAT DATA WITH
WESTERLY WINDS AT 15 KNOTS. A 071604Z SSMIS IMAGE SHOWS LITTLE TO
NO CONVECTIVE BANDING ASSOCIATED WITH A BROAD LLCC. UPPER-LEVEL
ANALYSIS SHOWS MODERATE TO STRONG VERTICAL WIND SHEAR (20-30 KNOTS)
WITH SOME MODERATE DIFFLUENCE. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 18 TO 23 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 LOW.

[Crostorm]

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 10.5S
65.5E, IS NOW LOCATED NEAR 11.8S 61.2E, APPROXIMATELY 745 NM
NORTHEAST OF LA REUNION. RECENT ANIMATED MULTISPECTRAL SATELLITE
IMAGERY SHOWS ISOLATED CONVECTION EMBEDDED ALONG THE EASTERN FLANK
OF A MOSTLY EXPOSED LOW-LEVEL CIRCULATION CENTER (LLCC). A 091406Z
37GHZ CORIOLIS PASS SHOWS FRAGMENTED SPIRAL BANDING AROUND THE LLCC.
THIS DISTURBANCE IS LOCATED UNDER THE WESTERN PERIPHERY OF THE UPPER-
LEVEL RIDGE AXIS, WITH LIGHT TO MODERATE (10-15 KTS) EASTERLY
VERTICAL WIND SHEAR (VWS) AND MODERATE POLEWARD DIFFLUENCE. MARGINAL
SEA SURFACE TEMPERATURES (SST) OF 26 DEGREES CELSIUS WILL BE A
LIMITING FACTOR FOR DEVELOPMENT. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1006 MB. BASED ON INCREASING VWS AND COOLING SSTS, THE
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS REMAINS LOW.

[euro6208]

10/1130 UTC 14.4S 58.1E T1.0/1.0 93S -- Southwest Indian

[Extratropical94]

2 - A broad ill-defined low level clockwise circulation is located at 0900Z near 14.2S/58.4E, moving south-westward at about 10kt. Associated convective activity is fluctuating. MSLP is estimated at 1007 hPa and winds are estimated at 10/15 kt near the centre, reaching 20/25 kt far away from the centre in the south-eastern quadrant due to gradient effect with the subtropical high pressures. Available NWP models are in good agreement and do not deepen the low within the next days. Oceanic heat content is marginal and a rather strong north wind-shear should remain on the expected west-southwestward track.