AXAU02 APRF 241922 IDW27700 TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION ISSUED BY AUSTRALIAN BUREAU OF METEOROLOGY TROPICAL CYCLONE WARNING CENTRE AT: 1920 UTC 24/12/2025 NAME: TROPICAL CYCLONE GRANT IDENTIFIER: 03U DATA AT: 1800 UTC LATITUDE: 11.9S LONGITUDE: 97.4E LOCATION ACCURACY: WITHIN 25NM (45 KM) MOVEMENT TOWARDS: WEST (270 DEG) SPEED OF MOVEMENT: 6 KNOTS (11 KM/H) MAXIMUM 10-MINUTE WIND: 35 KNOTS (65 KM/H) MAXIMUM 3-SECOND WIND GUST: 50 KNOTS (95 KM/H) CENTRAL PRESSURE: 997 HPA RADIUS OF 34-KNOT WINDS NE QUADRANT: 20 NM (35 KM) RADIUS OF 34-KNOT WINDS SE QUADRANT: 30 NM (55 KM) RADIUS OF 34-KNOT WINDS SW QUADRANT: 20 NM (35 KM) RADIUS OF 34-KNOT WINDS NW QUADRANT: 20 NM (35 KM) RADIUS OF 48-KNOT WINDS NE QUADRANT: RADIUS OF 48-KNOT WINDS SE QUADRANT: RADIUS OF 48-KNOT WINDS SW QUADRANT: RADIUS OF 48-KNOT WINDS NW QUADRANT: RADIUS OF 64-KNOT WINDS: NM ( KM) RADIUS OF MAXIMUM WINDS: 15 NM (30 KM) DVORAK INTENSITY CODE: T2.0/2.0/S0.0/24HRS STT:S0.0/06HRS PRESSURE OF OUTERMOST ISOBAR: 1004 HPA RADIUS OF OUTERMOST CLOSED ISOBAR: 120 NM (220 KM) FORECAST DATA DATE/TIME : LOCATION : LOC. ACCURACY: MAX WIND : CENTRAL PRESSURE (UTC) : DEGREES : NM (KM): KNOTS(KM/H): HPA +06: 25/0000: 11.9S 96.7E: 035 (070): 040 (075): 994 +12: 25/0600: 11.9S 96.0E: 045 (090): 040 (075): 994 +18: 25/1200: 11.9S 95.1E: 055 (100): 045 (085): 991 +24: 25/1800: 11.7S 94.5E: 055 (100): 045 (085): 991 +36: 26/0600: 11.5S 93.2E: 055 (100): 050 (095): 987 +48: 26/1800: 11.6S 92.0E: 065 (120): 050 (095): 987 +60: 27/0600: 11.9S 90.4E: 075 (135): 055 (100): 984 +72: 27/1800: 12.3S 88.6E: 080 (150): 060 (110): 981 +96: 28/1800: 13.2S 84.2E: 095 (175): 060 (110): 982 +120: 29/1800: 13.8S 80.2E: 115 (210): 060 (110): 981 REMARKS: TROPICAL CYCLONE GRANT HAS STARTED TO SHOW SIGNS OF INTENSIFICATION IN THE LAST FEW HOURS AFTER A PERIOD OF WEAKENING WEDNESDAY EVENING. COCOS ISLAND WIND AND PRESSURE OBSERVATIONS SHOW GRANT IS NOW APPROACHING THE COCOS (KEELING) ISLANDS. ASCAT-C SCATTEROMETRY AT 1525 UTC AND RCM-1 SYNTHETIC APERTURE RADAR (SAR) SATELLITE DATA AT 1153 UTC CLEARLY IDENTIFIED THE CENTRE POSITION OF GRANT. THIS DATA ALSO SHOWED THE INTENSITY TO BE 30 TO 35 KNOTS, WITH A SMALL GALE RADIUS AT BEST. HOWEVER, RECENT DEEP CONVECTION SHOWS THAT GRANT HAS SINCE STRENGTHENED AND IS LIKELY A CATEGORY 1 SYSTEM WITH AN INTENSITY OF 35 KNOTS. DVORAK ANALYSIS: FT BASED ON MET OF 2.0. DT 2.0 BASED ON A 0.2-0.3 WRAP CURVED BAND PATTERN WITH LOW CONFIDENCE. FT=2.0 AND CI=2.0. OBJECTIVE GUIDANCE ESTIMATES (1-MIN MEAN) AT 1730 UTC ARE ADT 45 KN, AIDT 43 KN, DPRINT 36 KN, DMINT (1208 UTC) 36 KN AND SATCON (1500 UTC) 42 KN. CIMMS UPPER WIND ANALYSIS AT 1200 UTC INDICATED NE'LY SHEAR OF 14 KN. MID-LEVEL DRY AIR REMAINS PRESENT TO THE SOUTHWEST WRAPPING AROUND THE SYSTEM ON THE WESTERN SIDE AND TO THE NORTH. A BROADER DRY AIRMASS IS ALSO BUTTING AGAINST THE SOUTHERN FLANK, WITH MOISTURE WRAPPING IN FROM THE NORTHEAST MAINTAINING THE TROPICAL DEVELOPMENT. MOISTURE WILL LIKELY CONTINUE TO BE A LIMITING FACTOR TO THE DEVELOPMENT OF GRANT OVER THE NEXT FEW DAYS. SSTS ARE MODERATELY HIGH AT APPROXIMATELY 28C ALONG THE TRACK. A SHORT WAVE UPPER TROUGH HAS PASSED TO THE SOUTH OF GRANT OVERNIGHT, HOWEVER, THERE WAS VERY LITTLE RESPONSE FROM THE SYSTEM. BEING A SMALL SYSTEM, IT IS FORECAST THAT GRANT COULD INTENSIFY IN A MARGINALLY FAVOURABLE ENVIRONMENT OVER THE NEXT FEW DAYS. FROM SATURDAY OR SUNDAY, ANOTHER UPPER TROUGH PASSES TO THE SOUTH AND INCREASED OUTFLOW AND DIVERGENCE MAY LEAD TO FURTHER INTENSIFICATION IN THE LONG TERM. HOWEVER, GRANT WILL BE WELL WEST OF 90E FROM SUNDAY WITH HIGH CONFIDENCE IN THE LONG TERM TRACK DUE TO A STRONG RIDGE TO THE SOUTH. COPYRIGHT COMMONWEALTH OF AUSTRALIA == THE NEXT BULLETIN FOR THIS SYSTEM WILL BE ISSUED BY: 25/0130 UTC.=