老農民版夜神月

  五級強烈熱帶氣旋  
編號：17 U ( 23 P )
名稱：Niran

  基本資料  
擾動編號日期：2021 年 02 月 26 日 22 時
JTWC升格日期:2021 年 03 月 01 日 09 時
命名日期　　：2021 年 03 月 02 日 04 時
撤編日期　　：2021 年 03 月 07 日 20 時
登陸地點　　：無

  巔峰時期資料  
近中心最強風速
斐濟氣象局 (FMS)：110 kt
聯合颱風警報中心(JTWC)：140 kt ( Cat.5 )
海平面最低氣壓   ：931 百帕

  擾動編號資料  
99P.INVEST.15kts.996mb.13.5S.147E

以上資料來自：FMS、JTWC、颱風論壇整理製作

dom

BoM認為未來48小時後發展為熱帶氣旋機會中等，數值支持成旋

A weak and broad low is embedded within the developing monsoon trough in the northwestern Coral Sea. The low is expected to develop over the next few days into next week, the rate dependent on the system's proximity to land, with a favourable environment increasing the likelihood of a tropical cyclone in the region next week.

Likelihood of a tropical cyclone in the Eastern Region on:
Saturday: Very LowSunday: Low
Monday: Moderate

老農民版夜神月

EC,GFS均支持後期達到較高強度

老農民版夜神月

JTWC0300Z評級Low

(1) AN AREA OF CONVECTION (INVEST 99P) HAS PERSISTED NEAR
15.7S 148.1E, APPROXIMATELY 153 NM EAST-NORTHEAST OF CAIRNS,
AUSTRALIA. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY INDICATES
FLARING, DISORGANIZED DEEP CONVECTION ASSOCIATED WITH A BROAD ILL-
DEFINED LOW-LEVEL CIRCULATION CENTER (LLCC). A 262201Z ASCAT-A IMAGE
REVEALS A BROAD, DEFINED CIRCULATION WITH 20-25 KNOT WINDS OVER THE
NORTHERN PERIPHERY. A 262314Z MHS 89GHZ IMAGE AND ANIMATED RADAR
IMAGERY FROM THE WILLIS ISLAND RADAR SHOW BROAD CYCLONIC TURNING
WITH A WEAK LLCC. ENVIRONMENTAL ANALYSIS DEPICTS A MARGINAL
ENVIRONMENT WITH STRONG EASTERLY VERTICAL WIND SHEAR OFFSET BY
ENHANCED POLEWARD OUTFLOW. SST VALUES ARE CONDUCIVE AT 29-30C.
GLOBAL MODELS INDICATE A SLOW, MEANDERING SOUTHWESTWARD TRACK OVER
THE NEXT TWO DAYS WITH SLOW DEVELOPMENT. MAXIMUM SUSTAINED SURFACE
WINDS ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
ESTIMATED TO BE NEAR 1002 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS LOW.

dom

BoM認為+72h發展為熱帶氣旋機會高

At 1pm AEST Saturday, a weak tropical low was developing in the northwestern Coral Sea, about 400km east of Cooktown.
The low is expected to continue to develop in favourable atmospheric conditions, and is expected to reach tropical cyclone strength by mid next week.
At this stage, the system is expected to remain slow moving off of the north tropical coast for the next several days, before moving away to the southeast late next week. Although a direct impact on the Queensland coast is currently considered a low risk, heavy rainfall and strong winds from the periphery of the system are possible about east tropical coastal and island areas during the next few days.

Likelihood of a tropical cyclone in the Eastern Region on:
Sunday: Low
Monday: Moderate
Tuesday: High

老農民版夜神月

JTWC18Z升格其為TD

SH, 99, 2021022712, , BEST, 0, 159S, 1489E, 20, 1002, DB, 0, , 0, 0, 0, 0, 1005, 150, 40, 0, 0, , 0, , 0, 0, INVEST, ,
SH, 99, 2021022718, , BEST, 0, 164S, 1489E, 25, 1000, TD, 0, , 0, 0, 0, 0, 1003, 180, 40, 0, 0, , 0, , 0, 0, INVEST, ,

老農民版夜神月

2200Z提升評級為Medium

(1) THE AREA OF CONVECTION (INVEST 99P) PREVIOUSLY LOCATED
NEAR 15.7S 148.1E IS NOW LOCATED NEAR 16.4S 148.9E, APPROXIMATELY
184 NM EAST OF CAIRNS, AUSTRALIA. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY, RADAR IMAGERY FROM WILLIS ISLAND, SURFACE OBSERVATIONS, AND
A 271827Z SSMIS 91GHZ MICROWAVE IMAGE INDICATE A CONSOLIDATING LOW
LEVEL CIRCULATION CENTER WITH FLARING DEEP CONVECTION IN THE
SOUTHERN SEMICIRCLE. ENVIRONMENTAL ANALYSIS DEPICTS A FAVORABLE
ENVIRONMENT WITH LOW TO MODERATE (15-20KTS) VERTICAL WIND SHEAR,
GOOD UPPER LEVEL OUTFLOW, AND WARM (29-30C) SEA SURFACE
TEMPERATURES. GLOBAL MODELS INDICATE A SOUTHWESTWARD TRACK TOWARD
THE COAST OF AUSTRALIA OVER THE NEXT 36-48 HOURS WITH STEADY
INTENSIFICATION. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 25
TO 30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1000
MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL
CYCLONE WITHIN THE NEXT 24 HOURS IS UPGRADED TO MEDIUM.

dom

BoM開始發報，預測兩天後成旋

Details of Tropical Low at 10:00 am AEST:

Intensity: tropical low, sustained winds near the centre of 45 kilometres per hour with wind gusts to 85 kilometres per hour.
Location: within 35 kilometres of 16.8 degrees South, 148.3 degrees East , 270 kilometres east of Cairns and 255 kilometres east northeast of Innisfail .
Movement: south at 11 kilometres per hour .

The tropical low is expected to remain slow moving off the north tropical coast while continuing to develop. It is expected to reach tropical cyclone strength on Tuesday morning. Although a direct coastal impact is not expected, gales are possible about exposed coastal and island areas as the system reaches cyclone strength. Heavy rainfall is also likely.

In the longer term, the system is expected to take a southeasterly track late in the week while remaining off the coast.