科科斯群岛以西二级热带气旋“格兰特”(03U/09S.Grant) - 逐渐西行

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全球热带气旋监测公报
预报：徐润杰、刘涛  签发：张玲  2025 年 12 月 26 日 10 时
“格兰特”向偏西方向移动

时  间: 26日08时（北京时）

海  域: 澳大利亚附近海域

命  名: “格兰特”，GRANT

中心位置:  南纬11.9度，东经93.5度

强度等级:  二级热带气旋

最大风力: 10级，26米/秒，相当于我国的强热带风暴级

中心气压: 990百帕

参考位置: 距离科科斯群岛偏西方向约365公里

变化过程: 过去24小时，“格兰特”强度由8级加强到10级

预报结论: “格兰特”将以每小时13公里左右的速度向偏西方向移动，强度维持



图1  卫星红外监测图像（北京时间2025年12月26日08时00分）

桑美和伊欧凯

ygsj24 发表于 2025-12-26 09:40
WTXS32 PGTW 260300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 09S ( ...

发展进入正轨，将缓慢加强，向MFR的责任区进发

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IDW27700
TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by AUSTRALIAN BUREAU OF METEOROLOGY TROPICAL CYCLONE WARNING CENTRE
at: 0704 UTC 26/12/2025
Name: Tropical Cyclone Grant
Identifier: 03U
Data At: 0600 UTC
Latitude: 11.8S
Longitude: 92.8E
Location Accuracy: within 25nm (45 km)
Movement Towards: west northwest (289 deg)
Speed of Movement: 8 knots (14 km/h)
Maximum 10-Minute Wind: 50 knots (95 km/h)
Maximum 3-Second Wind Gust: 70 knots (130 km/h)
Central Pressure: 990 hPa
Radius of 34-knot winds NE quadrant: 20 nm (35 km)
Radius of 34-knot winds SE quadrant: 50 nm (95 km)
Radius of 34-knot winds SW quadrant: 80 nm (150 km)
Radius of 34-knot winds NW quadrant: 30 nm (55 km)
Radius of 48-knot winds NE quadrant:
Radius of 48-knot winds SE quadrant: 20 nm (35 km)
Radius of 48-knot winds SW quadrant: 40 nm (75 km)
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: T3.0/3.0/S0.0/24HRS  STT:S0.0/06HRS
Pressure of outermost isobar: 1007 hPa
Radius of outermost closed isobar: 140 nm (260 km)
FORECAST DATA
Date/Time    : Location    : Loc. Accuracy: Max Wind   : Central Pressure
(UTC)        : degrees     :      nm  (km): knots(km/h): hPa
+06:  26/1200: 11.9S  92.2E:     035 (070):  050  (095):  990
+12:  26/1800: 11.9S  91.5E:     045 (085):  050  (095):  991
+18:  27/0000: 11.9S  90.7E:     055 (100):  050  (095):  991
+24:  27/0600: 12.0S  89.8E:     060 (110):  055  (100):  988
+36:  27/1800: 12.3S  87.9E:     065 (125):  055  (100):  988
+48:  28/0600: 12.9S  85.9E:     065 (125):  055  (100):  988
+60:  28/1800:             :              :            :     
+72:  29/0600:             :              :            :     
+96:  30/0600:             :              :            :     
+120: 31/0600:             :              :            :     
REMARKS:
Tropical Cyclone Grant continues to move westwards and maintain deep convection
near its centre.

Position is based on animated Vis satellite imagery with low cloud lines
visible to the northeast of the LLCC. The LLCC is analysed to the northeast of
the deep convection, consistent with the northeasterly shear that continues to
influence Grant.

Dvorak analysis: DT=3.0 based on curved band of 0.5. MET=3.5 based on D 24h
trend, PAT=3.0. FT and CI 3.0. Objective guidance estimates (1-min mean) at
0500 UTC: ADT 47 kn, AiDT 39 kn, DPRINT 53 kn, DMINT (0033 UTC) 57 kn.  Deep
convection near and to the west of the LLCC continues to persist and curved
bands have been limited to 0.5-0.6 over the past 6 hours. Earlier microwave
imagery (AMSR2 1914 UTC, and SSMIS at 2157 UTC and 0031UTC) show more extensive
curvature than the visible or IR imagery suggests. SMAP at 2343 UTC shows storm
force winds to the southwest of Grant's centre. ASCAT at 0313 UTC doesn't
capture all of the system, however, captures at least 45 kn in the southwest
quadrant. Intensity is analysed at 50 knots with little change in the last 6
hours, and is consistent with the SMAP, ASCAT, and most of the objective aids.
Dvorak, and the ADT and AiDT, remain a little below the analysed intensity.  
The environment surrounding Grant appears to be maintaining sufficient
atmospheric moisture despite dry air wrapping around the west and north. This
dry air is forecast to continue to wrap to the east and limit intensification.
Moderate northeasterly shear (CIMSS 20.2 kt at 18Z) continues to influence
Grant, and we can see a somewhat sheared appearance on the satellite, though
convection continues to develop near and southwest of the centre. Slow, limited
development is favoured with warm SSTs and good poleward outflow. However,
being a small system, Grant may continue to be subject to intensity
fluctuations.

The track remains consistent among guidance, with continued westward movement
under the influence of a mid-level ridge to the south. Grant is forecast to
move west of 90  E and out of the Australian region during Saturday. At this
time, an upper trough passing to the south may provide increased outflow and
divergence, with some slight further intensification possible.

Copyright Commonwealth of Australia
==
The next bulletin for this system will be issued by: 26/1330 UTC.

---

IDW24010
Australian Bureau of Meteorology
Tropical Cyclone Warning Centre

TROPICAL CYCLONE INFORMATION BULLETIN
Issued at 2:41 pm WST on Friday 26 December 2025

Tropical Cyclone Grant (Category 2) was located at 2:00 pm AWST (12:30 pm CCT)
near 11.8S 92.8E,
that is 440 km west of Cocos (Keeling) Islands and moving west northwest at 14
kilometres per hour.

Tropical Cyclone Grant is moving west over the Indian Ocean, now well to the
west of Cocos (Keeling) Islands.

Tropical Cyclone Grant will not have any further direct impacts to the Cocos
(Keeling) Islands.


The next Information Bulletin will be issued at 9:00 pm AWST Friday 26 December.

	Time (AWST)	Intensity Category	Latitude (decimal deg.)	Longitude (decimal deg.)	Estimated Position Accuracy (km)
0hr	2 pm December 26	2	11.8S	92.8E	45
+6hr	8 pm December 26	2	11.9S	92.2E	70
+12hr	2 am December 27	2	11.9S	91.5E	85
+18hr	8 am December 27	2	11.9S	90.7E	100
+24hr	2 pm December 27	2	12.0S	89.8E	110
+36hr	2 am December 28	2	12.3S	87.9E	125
+48hr	2 pm December 28	2	12.9S	85.9E	125
+60hr	2 am December 29	tropical low	XXX	XXX	XXX
+72hr	2 pm December 29	tropical low	XXX	XXX	XXX