開梅

花蓮今天可是維持了一整天的好天氣,連前幾天傍晚的大雨也沒出現吔

uodam64402

這是由ASCAT（METOP_B）衛星掃瞄風場，在臺灣時間2014年6月9日21:30~33分，所掃瞄到的海面風場資料，這次很幸運的是，連同已經被撤遍的93W的LLCC（在下圖中，處在尖閣諸島／釣魚臺群島附近）也都有疑似被掃到。由於圖片又被「20N、120E」的分割條件給限制住了，為了使臺灣為主體，這邊就用「28N~18N、114E~129E」作四個圖片的部分組合。




由此圖片可以看出來，由於宮古島、大重山地方仍然受到已撤遍的93W與其相關的偏南風，9日晚間仍然吹著南風，而琉球本島也是吹著東南風（由晚間日本氣象廳所查得）；但是因為臺灣臺東、綠島受到94W風場的因素，9日晚間已經開始吹起偏北風，而8日吹偏南風的高屏沿海地區，9日晚間也開始在圖片中，或是中央氣象局的觀測資料中，吹起偏北風。

再從風場圖旗子可以得知，最大風場還是在中心偏南邊。

桜slime

剛剛高雄氣壓跌破了998,現在氣壓997.9hPa
就連台灣北部都有站點氣壓跌破1000hPa:o

這麽看來,94W正在增強,成為輕度颱風米塔的機會不低,
就看一會小J會不會發GW呢:)

colinwoo

桜slime 發表於 2014-6-10 02:46
剛剛高雄氣壓跌破了998,現在氣壓997.9hPa
就連台灣北部都有站點氣壓跌破1000hPa

這可能是因為94W是個季風低壓。季風低壓的一個特點是氣壓總是比其他類型的熱帶系統要低。現在94W離台灣不遠，所以台灣這些地方有這樣的氣壓是挺正常的。個人認為不可以因為這樣就評論它的未來發展耶

jwpk9899

JTWC評級LOW
現在94W真的離台灣好近
不過CWB定位好像是裸奔狀態
(1) AN AREA OF CONVECTION HAS PERSISTED NEAR 21.5N 121.5E,
APPROXIMATELY 210 NM SOUTH OF TAIPEI, TAIWAN. ANIMATED INFRARED
SATELLITE IMAGERY DEPICTS A BROAD AND POORLY DEFINED LOW LEVEL
CIRCULATION CENTER (LLCC) LOCATED ALONG A BAROCLINIC BOUNDARY WITH
CONVECTION ALONG THE EASTERN PERIPHERY. A 091910Z SSMI 37GHZ
MICROWAVE IMAGE SHOWS BROAD CYCLONIC TURNING ALONG THE SOUTHERN TIP
OF TAIWAN WITH THE POSSIBILITY OF MULTIPLE CIRCULATIONS LOCATED
ALONG THE BAROCLINIC BOUNDARY AS SUGGESTED BY A 091333Z ASCAT PASS.
UPPER LEVEL ANALYSIS REVEALS A MARGINAL ENVIRONMENT AS THE LLCC IS
LOCATED NORTH OF THE RIDGE AXIS WITH FAIR OUTFLOW AND LOW TO
MODERATE (10 TO 15 KNOTS) VERTICAL WIND SHEAR. DYNAMIC MODEL
GUIDANCE SUGGEST THIS SYSTEM WILL RAPIDLY ACCELERATE TO THE
NORTHEAST AND TRANSITION INTO A FULLY BAROCLINIC SYSTEM AS IT
BECOMES EMBEDDED INTO THE MID-LATITUDE WESTERLY FLOW. MAXIMUM
SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA
LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1001 MB. THE POTENTIAL FOR
THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS IS LOW.

krichard2011

疑似有多重LLCC的情形 樓上報文也有提到
中央氣象局跟JTWC的定位完全一樣 皆在 21.5N 121.5E (我打紅色X的地方)
從雷達動畫來看更清楚 目前LLCC似乎真有裸露的情形
不過在這LLCC的東南方 也有疑似LLCC正在建立的情形 抑或是中尺度渦旋?
只能觀察未來是否能順利取代

ben811018

熱帶低壓還在蘭嶼附近海域，今天將持續往東北東移動，
速度也會逐漸加快，隨著緯度增加，大氣環境越不支持發展，
未來將近一部轉化為溫帶氣旋。


這個熱帶低壓對台灣的天氣影響不大，
鋒面結構被破壞掉了，所以鋒面型態變得不是很明顯，
帶下來的北風把雲系都往巴士海峽推，
台灣的天氣反而穩定許多，不過東半部因為在迎風面的關係，
天氣還是很不穩定，一整天都有局部降雨發生。


熱帶低壓串聯整個低壓槽，隨著系統加速往東北移動，
也會逐漸脫離，預計南海北部還會有系統生成，
對台灣是否有威脅仍有待觀察，
不過，要提醒的是，因為離台灣不遠，
一旦有系統出現，應變時間相當短....

Meow

暌違一個多月的 Medium。:lol 指出系統小，讓數值預報搞錯位置。



THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 21.5N
121.5E, IS NOW LOCATED NEAR 21.8N 122.3E, APPROXIMATELY 185 NM SOUTH-
SOUTHWEST OF ISHIGAKIJIMA, JAPAN. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI) DEPICTS A WELL-DEFINED, EXPOSED LOW-LEVEL CIRCULATION
CENTER (LLCC) WITH ISOLATED BURSTS OF DEEP CONVECTION SHEARED EAST
AND SOUTHEAST OF THE LLCC. A 092344Z SSMIS IMAGE INDICATES
FORMATIVE, WEAK BANDING DISPLACED OVER THE SOUTHERN SEMI-CIRCLE OF
THE SYSTEM. A 100104Z ASCAT IMAGE SHOWS A SYMMETRIC CIRCULATION WITH
15 TO 20 KNOT WINDS AND STRONGER FLOW OVER THE SOUTHERN FLANK OF THE
SYSTEM, ASSOCIATED WITH THE AFOREMENTIONED WEAK CONVECTIVE BANDING.
MSI AND ASCAT IMAGERY INDICATE THAT THE LLCC IS LOCATED WELL SOUTH
OF A WEAK BAROCLINIC ZONE, WHICH EXTENDS FROM NORTHERN TAIWAN SOUTH-
SOUTHWESTWARD INTO THE SOUTH CHINA SEA. UPPER-LEVEL ANALYSIS SHOWS
THAT THE LLCC IS LOCATED JUST POLEWARD OF THE SUBTROPICAL RIDGE AXIS
IN A MARGINAL ENVIRONMENT WITH LOW TO MODERATE (15 TO 20 KNOTS)
VERTICAL WIND SHEAR ASSOCIATED WITH UPPER-LEVEL WEST-SOUTHWESTERLY
FLOW. DUE TO THE SMALL SIZE OF THE SYSTEM, THE DYNAMIC MODELS ARE
NOT INITIALIZING THE CIRCULATION ACCURATELY. HOWEVER, THE MODEL
FIELDS INDICATE A TWO TO THREE DAY PERIOD OF POTENTIAL DEVELOPMENT
BEFORE THE SYSTEM BECOMES ABSORBED IN THE BAIYU BOUNDARY SOUTH OF
KYUSHU. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20
KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1001 MB.
BASED ON THE STRENGTH AND SYMMETRY OF THE LOW-LEVEL WIND FIELD, THE
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS IS UPGRADED TO MEDIUM.