TC Watch / 熱帶氣旋 > Selected TC Review / 重要熱帶氣旋回顧 > 201506W (NOUL 紅霞) [Refresh 更新]
 201506W (NOUL 紅霞) - Profile 檔案 |
(Issued on June 11, 2015)
(於 2015 年 6 月 11 日發出)
Brief profile of NOUL 紅霞小檔案:
| JTWC number 聯合颱風警報中心 (JTWC) 號碼 | 06W |
| International number 國際編號 | 1506 |
| Period of existence 生存時期 (JTWC) | 2015/05/03 08 HKT - 2015/05/13 02 HKT |
| Lifetime 壽命 (JTWC) | 9.75 days 日 |
| Maximum 1-minute wind (JTWC) JTWC 一分鐘平均最高中心風速 | 140 knots 節 (Category 5 Super Typhoon 五級超級颱風) |
| Minimum pressure (JTWC) JTWC 最低氣壓 | 918 hPa 百帕 |
| Highest TC signal by HKO (if applicable) 香港天文台發出最高熱帶氣旋警告信號 |
N/A 不適用 |
| Closest point of approach by HKO (if applicable) 香港天文台所示之最接近距離 (如適用) |
N/A 不適用 |
| Time of closest approach by HKO (if applicable) 香港天文台所示之最接近時間 (如適用) |
N/A 不適用 |
| Lowest pressure recorded at HKO (if applicable) 香港天文台錄得的最低氣壓 (如適用) |
N/A 不適用 |
TC track from HKWW 本站的熱帶氣旋路徑圖:
| Past HKWW Bulletins on NOUL 本站有關紅霞的發佈 |
Please click here for bulletins on NOUL. 請按這裡。
| Storm Summary 氣旋摘要 |
Unless otherwise stated, all times below are in Hong Kong Standard Time (UTC+8)
除非特別註明，下文時間均為香港標準時間 (協調世界時加 8 小時)
NOUL is the second category 5 super typhoon in the western Pacific this year. It developed as a tropical disturbance at the beginning of May, gradually gathering strength and intensified into tropical depression 06W on May 3. At its formation, the vertical wind shear is somewhat stronger in the southern side of the cyclone, and development was rather limited. Meanwhile, 06W was at that time situated south of a small break in the subtropical ridge and hence drifted north. 06W intensified into a tropical storm early on May 4, and was named NOUL by the JMA. It decelerated and turned west in a weak steering environment.
In the next two days, NOUL's convections were limited to its northern and western sides. It took a southward dip on May 5 and passed through Yap that night as it started to develop a low-level eye, which was initially discernible through microwave satellite imagery. The JTWC upgraded NOUL into a typhoon at 2 am May 6. During the day, NOUL's eye became more prominent; agencies that use 10-minute average wind speeds upgraded NOUL into a typhoon that night.
As vertical wind shear over the region relaxed and outflow improved, NOUL's convections became more symmetrical on May 6 and 7. It also accelerated towards the west-northwest as the subtropical ridge strengthened. The ridge's western edge was situated near the eastern end of Luzon Strait, and a recurving scenario was generally adopted by various agencies. NOUL's rate of intensification was very modest on May 8 and May 9, as its eye lacked stability and disappeared from satellite images at times. The JTWC even lowered its estimated intensity from 105 knots (195 km/h) to 95 knots (176 km/h) in the morning of May 9.
An episode of rapid intensification took place during that night. NOUL's central dense overcast consolidated into an annular, tight patch of convections within a period of 12 hours. Its eye cleared early on May 10 as the storm approached northeastern Luzon. The JTWC upgraded NOUL into a 140-knot (259 km/h) category 5 super typhoon at 8 am, while JMA's estimated intensity was 105 knots (195 km/h) with a central pressure of 915 hPa.
Due to its proximity to landmass, NOUL's peak intensity did not last long. Its eyewall warmed during the day and its eye shrank in size. It briefly touched Luzon's northeastern tip at around 7 pm as it reached the western periphery of the subtropical ridge and turned north. NOUL's degradation led various agencies to lower its estimated strength during the night of May 10.
In light of NOUL's approach, Taiwan's Central Weather Bureau issued a sea typhoon warning at 8:30 am May 10. The storm maintained a distance of around 200 km from the Island as it recurved and weakened gradually while crossing Luzon Strait, and the warning was lifted at 8:30 pm the next day. NOUL entered the westerlies soon after recurvature and accelerated quickly to around 50 km/h. Because of strong vertical wind shear and rapidly decreasing sea temperatures along its track, NOUL weakened steadily and its convections were heavily sheared. It neared Ryukyu Islands early on May 12, and within several hours' time it reached seas just southeast of Kagoshima. The JMA ceased tropical cyclone warning at 8 pm as it determined that NOUL's extratropical transition was complete; at that time NOUL was approaching Tokyo. In HKO's weather report, NOUL was once predicted to move at 90 km/h just prior to the completion of extratropical transition, a very high speed that is rarely seen even for transitioning cyclones.
紅霞是本年西北太平洋的第二個五級超級颱風。它在 5 月初發展成熱帶擾動，於 3 日逐漸增強為熱帶低氣壓 06W。06W 形成初期，其南端的垂直風切變較強，令該區發展速度較慢。當時 06W 正處於副熱帶高壓脊一細小弱點以南，因而向北飄移。06W 於 4 日增強為熱帶風暴，被日本氣象廳命名為紅霞。在微弱流場中，紅霞減速並轉向西移。
於其後兩天，紅霞大部份對流仍局限於其西北兩側。它於 5 日略為南移，當晚經過雅蒲島並開始發展出低層風眼，於微波衛星雲圖中可見。聯合颱風警報中心遂於 6 日上午 2 時將其升格為颱風。紅霞的風眼於當日日間更趨明顯，使用 10 分鐘平均風速標準的氣象台於當晚將其升格為颱風。
隨著該區的垂直風切變下降而輻散轉佳，紅霞的對流於 6 及 7 日變得較為對稱。由於副高增強，紅霞加速向西北偏西移動。當時副高西沿於呂宋海峽東端，因此大部分機構均預測紅霞將於到達較高緯度後轉向。紅霞於 8 及 9 日只略為增強，其風眼較不穩定，間中更於衛星雲圖上消失。聯合颱風警報中心曾於 9 日早上將其估計強度由 105 節 (每小時 195 公里) 下調至 95 節 (每小時 176 公里)。
紅霞於 9 日晚快速增強，其中心密集雲區於 12 小時內整合為一環狀緊密的對流團。風暴於 10 日早段靠近呂宋東北部，其風眼變得清晰無雲，聯合颱風警報中心於上午 8 時將其升格為五級超級颱風 (強度 140 節 / 每小時 259 公里)，而日本氣象廳對其估計強度則為 105 節 (每小時 195 公里)，中心氣壓 915 百帕斯卡。
由於紅霞靠近陸地，它維持巔峰強度的時間不長。紅霞眼牆溫度於當天日間升高，風眼逐漸縮小。它於晚上約 7 時擦過呂宋東北角，並沿副高西部轉向北移。因應紅霞的結構轉差，各氣象台均於 10 日晚間下調其強度估計。
台灣方面，因紅霞逐漸逼近，中央氣象局於 10 日早上 8 時 30 分發出海上颱風警報。紅霞於橫過呂宋海峽時轉向並減弱，與台灣主島維持約 200 公里距離，警告於翌日晚上 8 時 30 分取消。紅霞於轉向後不久即進入西風帶，致其加速至每小時約 50 公里。受強烈垂直風切變及海溫不斷下降的影響，紅霞穩定地減弱，而其對流則被嚴重切離。風暴於 12 日早段靠近琉球群島，數小時後已達鹿兒島東南方近海。日本氣象廳於當晚 8 時認為紅霞已完成溫帶氣旋轉化，風暴當時正趨向東京；較早時香港天文台的天氣報告則曾預計紅霞會以每小時約 90 公里的速度移動，可見風暴轉化時移速之高。
| Figures 圖片 |
Figures 1a and 1b - Steering flow charts at 8 am May 5 (left) and May 9 (right)
圖 1a 及 1b - 5 月 5 (左) 及 9 日 (右) 上午 8 時之駛流圖
Figure 2 - Forecast tracks from different agencies on May 8
圖 2 - 5 月 8 日各氣象台之預測路徑圖
Figure 3 - Satellite image of NOUL at peak intensity
圖 3 - 紅霞於巔峰強度時之衛星雲圖
Figure 4 - NOUL's estimated wind field at 2 pm May 10
圖 4 - 紅霞於 5 月 10 日下午 2 時之估算風場圖
Figures 5a and 5b - Wind field analysis at around 9 am May 10 (left) and 9 pm May 11 (right)
圖 5a 及 5b - 5 月 10 日上午 9 時 (左) 及 11 日晚上 9 時 (右) 之風場分析
Figures 6a and 6b - Radar images of NOUL as it crossed Luzon Strait (left) and neared Okinawa (right)
圖 6a 及 6b - 紅霞於橫過呂宋海峽 (左) 及靠近沖繩島 (右) 時之雷達圖
Figure 7 - NOUL's estimated wind field at 8 am May 12. Note the very weak winds in the navigable semicircle due to the cyclone's quick speed across the Pacific after recurvature.
圖 7 - 紅霞於 5 月 12 日上午 8 時之估算風場圖。由於紅霞轉向後以高速橫過太平洋，其可航半圓之風速十分低。
Figure 8 - NOUL undergoing extratropical transition as it passed the Ryukyu Islands
圖 8 - 紅霞於掠過琉球群島時正轉化為溫帶氣旋
| Other Data 其他數據 |
Table 1: Track data from HKWW:
表一 : 香港天氣觀測站之路徑資料
| YYMMDDZZ Lat Long Wind 15050300 078N1416E 025 15050306 082N1413E 025 15050312 088N1411E 030 15050318 094N1407E 035 15050400 096N1403E 040 15050406 098N1400E 040 15050412 097N1397E 045 15050418 097N1394E 050 15050500 096N1389E 050 15050506 096N1387E 055 15050512 096N1386E 055 15050518 095N1383E 060 15050600 095N1378E 065 15050606 096N1369E 065 15050612 098N1360E 070 15050618 101N1352E 075 15050700 106N1342E 085 15050706 114N1331E 090 15050712 117N1322E 095 15050718 118N1312E 095 15050800 121N1302E 095 15050806 127N1291E 095 15050812 133N1281E 100 15050818 138N1270E 100 15050900 143N1263E 100 15050906 149N1252E 105 15050912 154N1245E 115 15050918 161N1239E 130 15051000 170N1233E 140 15051006 179N1226E 140 15051012 186N1224E 130 15051018 196N1223E 115 15051100 206N1220E 105 15051106 218N1225E 095 15051112 233N1236E 080 15051118 259N1257E 075 15051200 281N1287E 070 15051206 308N1323E 060 |
Table 2: Track data from JTWC:
表二 : 聯合颱風警報中心之路徑資料
ID Name YYMMDD ZZZZ Lat Long Basin Wind Pres 06W NOUL 150512 1800 37.6N 144.1E WPAC 40 993 |
Last Accessed 最近訪問日期: Sun Sep 08 2024 12:46:54 HKT
Last Modified 最近修訂日期: Mon Jul 24 2023
