AXAU02 APRF 270102
IDW27700
TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
ISSUED BY AUSTRALIAN BUREAU OF METEOROLOGY TROPICAL CYCLONE WARNING
CENTRE
AT: 0101 UTC 27/12/2025
NAME: TROPICAL CYCLONE GRANT
IDENTIFIER: 03U
DATA AT: 0000 UTC
LATITUDE: 11.8S
LONGITUDE: 90.1E
LOCATION ACCURACY: WITHIN 15NM (30 KM)
MOVEMENT TOWARDS: WEST (272 DEG)
SPEED OF MOVEMENT: 8 KNOTS (15 KM/H)
MAXIMUM 10-MINUTE WIND: 50 KNOTS (95 KM/H)
MAXIMUM 3-SECOND WIND GUST: 70 KNOTS (130 KM/H)
CENTRAL PRESSURE: 986 HPA
RADIUS OF 34-KNOT WINDS NE QUADRANT: 30 NM (55 KM)
RADIUS OF 34-KNOT WINDS SE QUADRANT: 30 NM (55 KM)
RADIUS OF 34-KNOT WINDS SW QUADRANT: 40 NM (75 KM)
RADIUS OF 34-KNOT WINDS NW QUADRANT: 40 NM (75 KM)
RADIUS OF 48-KNOT WINDS NE QUADRANT: 15 NM (30 KM)
RADIUS OF 48-KNOT WINDS SE QUADRANT: 20 NM (35 KM)
RADIUS OF 48-KNOT WINDS SW QUADRANT: 20 NM (35 KM)
RADIUS OF 48-KNOT WINDS NW QUADRANT: 15 NM (30 KM)
RADIUS OF 64-KNOT WINDS:   NM (  KM)
RADIUS OF MAXIMUM WINDS: 15 NM (30 KM)
DVORAK INTENSITY CODE: T3.5/3.5/D0.5/24HRS  STT:S0.0/06HRS
PRESSURE OF OUTERMOST ISOBAR: 1006 HPA
RADIUS OF OUTERMOST CLOSED ISOBAR: 110 NM (205 KM)
FORECAST DATA
DATE/TIME    : LOCATION    : LOC. ACCURACY: MAX WIND   : CENTRAL
PRESSURE
(UTC)        : DEGREES     :      NM  (KM): KNOTS(KM/H): HPA
+06:  27/0600: 11.8S  89.3E:     025 (050):  055  (100):  986
+12:  27/1200: 12.0S  88.4E:     035 (070):  060  (110):  983
+18:  27/1800: 12.1S  87.5E:     045 (085):  060  (110):  983
+24:  28/0000: 12.3S  86.6E:     050 (090):  060  (110):  983
+36:  28/1200: 12.9S  84.6E:     055 (105):  060  (110):  983
+48:  29/0000:             :              :            :
+60:  29/1200:             :              :            :
+72:  30/0000:             :              :            :
+96:  31/0000:             :              :            :
+120: 01/0000:             :              :            :
REMARKS:
TROPICAL CYCLONE GRANT CONTINUES TO MAINTAIN VIGOROUS CONVECTION
WITHIN ITS
CENTRAL DENSE OVERCAST, WHICH IS OFFSET SLIGHTLY TO THE WEST OF THE
LOW LEVEL
CENTRE. THE IR SIGNATURE LIKEWISE SHOWS THE EFFECTS OF LOW TO
MODERATE EASTERLY
SHEAR, ANALYSED AT 15 KNOTS ON THE 2100 UTC CIMSS UPPER WIND
ANALYSIS. POSITION
IS BASED ON ANIMATED SATELLITE IMAGERY AND EXTRAPOLATION FROM THE
2221 UTC GMI
PASS.

DVORAK ANALYSIS: DT=3.0 BASED ON A SHEAR PATTERN, WITH THE ESTIMATED
LOW LEVEL
CENTRE JUST UNDER 1/3 DEGREE INTO THE DENSE OVERCAST. MET=3.5 BASED
ON 24H D-
TREND, PAT=3.5. FT AND CI 3.5. RECENT OBJECTIVE GUIDANCE ESTIMATES
(1-MIN MEAN)
ARE ADT 55 KNOTS (2245 UTC), AIDT 55 KNOTS (2245 UTC), DPRINT 56
KNOTS (2300
UTC) DMINT 50 KNOTS (2224 UTC), SATCON 54 KNOTS (2045 UTC). INTENSITY
ESTIMATED
AT 50 KNOTS (10 MINUTE MEAN) BASED ON SUBJECTIVE DVORAK AND PAYING
THE UNUSUAL
CONSISTENCY OF THE OBJECTIVE AIDS. STRUCTURE IS EXTRAPOLATED FROM THE
1209 UTC
SAR PASS.

GRANT IS A SMALL SYSTEM UNDER LOW TO MODERATE SHEAR. CURRENT ANALYSED
SSTS ARE
27-28C, THOUGH SLIGHTLY WARMER ALONG THE FORECAST TRACK FURTHER WEST.
MIMIC-TPW
IMAGERY SHOWS DRY AIR WRAPPING AROUND THE NORTH SIDE OF GRANT BUT NOT
YET
PENETRATING THE CORE. WITH MOST ENVIRONMENTAL FACTORS NEAR NEUTRAL,
THE
FORECAST IS FOR VERY GRADUAL INTENSIFICATION OF GRANT IN THE SHORT
TERM, NOTING
THAT AS A VERY SMALL SYSTEM GRANT MAY REACT QUICKLY TO ANY CHANGES IN
ENVIRONMENTAL CONDITIONS. AS GRANT WILL SHORTLY MOVE INTO THE LA
REUNION AREA
OF RESPONSIBILITY, THE FORECAST DOES NOT EXTEND BEYOND 36 HOURS,
HOWEVER MOST
NUMERICAL GUIDANCE INDICATES FURTHER INTENSIFICATION IS LIKELY IN THE
MEDIUM
TERM AS GRANT CONTINUES TO MOVE WEST SOUTHWEST THROUGH MORE
FAVOURABLE
ENVIRONMENTAL CONDITIONS IN THE CENTRAL INDIAN OCEAN.

COPYRIGHT COMMONWEALTH OF AUSTRALIA
==
THERE WILL BE NO FURTHER BULLETINS FOR THIS SYSTEM ISSUED BY THE
AUSTRALIAN TROPICAL CYCLONE WARNING CENTRE.=