KETSANA made landfall in central Vietnam yesterday and gradually weakened into a tropical storm. At 08 HKT, KETSANA was centred about 210 km (110 NM) WSW of Da Nang.
KETSANA is the 90th name in the tropical cyclone name list. This name was contributed by Laos, and is the name of a type of trees. This name was last used in 2003.
KETSANA is about to make landfall in central Vietnam. At 14 HKT, KETSANA was centred about 100 km (55 NM) SE of Da Nang.
凱薩娜即將登陸越南中部。在 14 HKT，凱薩娜集結在峴港東南約 100 公里 (55 海里)。
TC Naming 氣旋命名
KETSANA is the 90th name in the tropical cyclone name list. This name was contributed by Laos, and is the name of a type of trees. This name was last used in 2003.
KETSANA has intensified further into a category 2 typhoon. At 20 HKT, KETSANA was centred about 770 km (410 NM) SSW of Hong Kong. All tropical cyclone signals were cancelled at 19:15 HKT.
KETSANA is the 90th name in the tropical cyclone name list. This name was contributed by Laos, and is the name of a type of trees. This name was last used in 2003.
The subtropical ridge north of KETSANA has broken with a weakness developed in southeastern China. However, the northeast monsoon is expected to work together with the remaining (weak) steering flow from the ridge to push KETSANA towards Vietnam in the short term.
Current T-number: T5.0/5.0/D1.5/21 HRS
KETSANA's eye is now clearly discernible in IR image. KETSANA may still intensify a bit before making landfall in central Vietnam, after which rapid weakening follows.
現時的 T 號碼: T5.0/5.0/D1.5/21 HRS 凱薩娜的風眼現在於紅外線衛星雲圖中清晰可見。預料凱薩娜或可在登陸前增強少許，且於登陸後快速減弱。
Effects on Hong Kong 對香港的影響
Although KETSANA is moving away from Hong Kong, occasional rain and fresh winds are generally expected in the first half of tomorrow.
雖然凱薩娜正遠離本港，但預計香港仍會於明天前半部受大雨影響，風勢維持清勁。
Next Update 下次更新
19 HKT, 2009/09/29 (or earlier 或更早)
Other Images 其他圖像
JTWC Track 聯合颱風警報中心路徑圖
JMA Track 日本氣象廳路徑圖
HKO Satellite 香港天文台衛星圖
HKO Track 香港天文台路徑圖
Probabilities of TC Signals from HKO 香港天文台 (已) 發出 / 取消熱帶氣旋警告信號的機率
KETSANA has intensified into a typhoon. At 14 HKT, KETSANA was centred about 750 km (410 NM) SSW of Hong Kong.
凱薩娜增強為一颱風。在 14 HKT，凱薩娜集結在香港西南偏南約 750 公里 (410 海里)。
TC Naming 氣旋命名
KETSANA is the 90th name in the tropical cyclone name list. This name was contributed by Laos, and is the name of a type of trees. This name was last used in 2003.
The subtropical ridge north of KETSANA has broken with a weakness developed in southeastern China. However, the northeast monsoon is expected to work together with the remaining (weak) steering flow from the ridge to push KETSANA towards Vietnam in the short term.
Current T-number: T4.5/4.5/D1.0/15 HRS
KETSANA has intensified into a typhoon with an eye visible on visible imagery. It is expected to maintain strength or intensify slightly before landfall. It will weaken rapidly after making landfall in Vietnam.
現時的 T 號碼: T4.5/4.5/D1.0/15 HRS 凱薩娜增強為颱風，於可見光雲圖中風眼清晰可見。預料凱薩娜將於登陸前維持強度或稍作增強，並於登陸後快速減弱。
Effects on Hong Kong 對香港的影響
KETSANA's southeasterly airflow in its northeastern quadrant is interacting with the northeast monsoon to bring unsettled weather to Hong Kong. Rain will be heavy at times for today and tomorrow, with winds freshening from the northeast. Strong force winds may be observed in offshore waters and on high ground.
KETSANA's track speed has decreased. At 23 HKT, KETSANA was centred about 700 km (380 NM) S of Hong Kong. The HK Observatory issued the #1 Standby Signal at 22:15 yesterday.
KETSANA is the 90th name in the tropical cyclone name list. This name was contributed by Laos, and is the name of a type of trees. This name was last used in 2003.
The subtropical ridge north of KETSANA has weakened a bit so that some northward component was observed in KETSANA's track, but the ridge is still strong enough to steer KETSANA to the west in the near term. It will make landfall in Vietnam two days later.
Current T-number: T3.5/3.5/D1.0/24 HRS
Good outflow will allow KETSANA to intensify into a typhoon. However, as ocean heat content decreases near Vietnam, KETSANA is not expected to intensify to beyond category 1.
現時的 T 號碼: T3.5/3.5/D1.0/24 HRS 良好的輻散將令凱薩娜增強至颱風強度。但由於越南附近的海面熱能較低，預料凱薩娜將不會增強至高於一級颱風之強度。
Effects on Hong Kong 對香港的影響
KETSANA's southeasterly airflow in its northeastern quadrant may interact with the northeast monsoon to bring unsettled weather to Hong Kong in the next two days. Winds will also strengthen from the northeast.
KETSANA is travelling due west in the South China Sea, and has intensified into a severe tropical storm. At 14 HKT, KETSANA was centred about 390 km (210 NM) ESE of Paracel Islands (Xisha).
KETSANA is the 90th name in the tropical cyclone name list. This name was contributed by Laos, and is the name of a type of trees. This name was last used in 2003.
The subtropical ridge north of KETSANA is expected to steer it towards the west. The subtropical ridge is expected to weaken later, allowing a slight poleward component in its track. KETSANA should make landfall in Vietnam about two days later.
Current T-number: T3.5/3.5/D1.0/24 HRS
Good outflow will allow KETSANA to intensify into a typhoon. However, as ocean heat content decreases near Vietnam, KETSANA is not expected to intensify to beyond category 1.
現時的 T 號碼: T3.5/3.5/D1.0/24 HRS 良好的輻散將令凱薩娜增強至颱風強度。但由於越南附近的海面熱能較低，預料凱薩娜將不會增強至高於一級颱風之強度。
Effects on Hong Kong 對香港的影響
KETSANA's southeasterly airflow in its northeastern quadrant may interact with the northeast monsoon to bring unsettled weather to Hong Kong in the next two days. Winds will also strengthen from the northeast.
17W intensified into a tropical storm today, and was named KETSANA by the JMA. KETSANA is making landfall at eastern Luzon. At 14 HKT, KETSANA was centred about 120 km (60 NM) NNE of Manila.
KETSANA is the 90th name in the tropical cyclone name list. This name was contributed by Laos, and is the name of a type of trees. This name was last used in 2003.
A strong subtropical ridge is situated north of KETSANA and is expected to remain in place for the next 3 days. This will steer 17W westward across central/northern South China Sea. There are still a few models predicting that the ridge would weaken soon to allow significant poleward component, but this scenario is unlikely to occur. Nevertheless, such a possibility will be closely monitored.
Current T-number: T2.5/2.5/D0.5/18 HRS
KETSANA is about to make landfall at Luzon, and intensification should cease until it re-emerges. Inside South China Sea, KETSANA is expected to slow down, and this will allow time for intensification into a typhoon.
現時的 T 號碼: T2.5/2.5/D0.5/18 HRS 凱薩娜即將登陸呂宋，預料它將停止增強直至進入南海。進入南海後，預料凱薩娜的移速會減低，這將有望令凱薩娜逐步增強至颱風強度。
Effects on Hong Kong 對香港的影響
Although the possibility is now lower, KETSANA may still enter the so-called Cuming area 2 days later, in which the moist southeasterly winds from the system may interact with the northeast monsoon to bring unsettled weather to Hong Kong.
A strong subtropical ridge is situated north of 17W and is expected to remain in place for the next 5 days. This will steer 17W westward towards central South China Sea. Currently there are a few models predicting that the ridge would weaken next week to allow more poleward component, which is deemed rather unlikely at present.
Current T-number: T2.0/2.0/INT OBS
17W is still slowly developing with convective clouds displaced to the west, leaving a partially exposed low-level circulation centre. 17W is expected to intensify slightly before making landfall on Luzon. It will then weaken slightly while on land and re-intensify as it enters South China Sea.
17W may enter the so-called Cuming area 3 days later, in which the moist southeasterly winds from the system interacts with the northeast monsoon to bring unsettled weather to Hong Kong.
17W 可能於三天後進入奎明範圍，其東北面之濕潤東南風或會與東北季候風相遇，令香港天氣變得不穩定。
Next Update 下次更新
19 HKT, 2009/09/26 (or earlier 或更早)
Other Images 其他圖像
JTWC Track 聯合颱風警報中心路徑圖
N/A 沒有資料
JMA Track 日本氣象廳路徑圖
HKO Satellite 香港天文台衛星圖
HKO Track 香港天文台路徑圖
Probabilities of TC Signals from HKO 香港天文台 (已) 發出 / 取消熱帶氣旋警告信號的機率
Active Tropical Cyclone(s) 正活躍之熱帶氣旋
