Tropical Storm Haitang (2011)

Tropical Storm Haitang
Tropical Storm Haitang at peak intensity on September 26
Meteorological history
FormedSeptember 24, 2011
DissipatedSeptember 27, 2011
Tropical storm
10-minute sustained (JMA)
Highest winds65 km/h (40 mph)
Lowest pressure996 hPa (mbar); 29.41 inHg
Tropical storm
1-minute sustained (SSHWS/JTWC)
Highest winds65 km/h (40 mph)
Lowest pressure996 hPa (mbar); 29.41 inHg
Overall effects
Fatalities7
Missing4
DamageUnknown
Areas affectedChina, Southeast Asia

Part of the 2011 Pacific typhoon season

Tropical Storm Haitang was a weak tropical cyclone which impacted China and Southeast Asia. The nineteenth named storm of the below-average 2011 Pacific typhoon season, Haitang developed from a disturbance in the South China Sea. After being recognized as a tropical depression on September 24, Haitang would peak as a minimal tropical storm before making landfall in Hue, Vietnam. Haitang would rapidly weaken once inland, dissipating in Laos in September 27.

Meteorological history[edit]

Map plotting the storm's track and intensity, according to the Saffir–Simpson scale
Map key
  Tropical depression (≤38 mph, ≤62 km/h)
  Tropical storm (39–73 mph, 63–118 km/h)
  Category 1 (74–95 mph, 119–153 km/h)
  Category 2 (96–110 mph, 154–177 km/h)
  Category 3 (111–129 mph, 178–208 km/h)
  Category 4 (130–156 mph, 209–251 km/h)
  Category 5 (≥157 mph, ≥252 km/h)
  Unknown
Storm type
triangle Extratropical cyclone, remnant low, tropical disturbance, or monsoon depression

At 15:00 UTC on September 21, the Joint Typhoon Warning Center (JTWC) began to monitor a low-pressure area persisting around 260 nautical miles south of Hong Kong.[1] As the next three days progressed, the disturbance meandered northwards, strengthening slightly. On September 24, the Japan Meteorological Agency (JMA) would recognize the disturbance as a tropical depression east of Vietnam.[2] Later that day, the JTWC would issue a Tropical Cyclone Formation Alert, stating that the low could develop into a tropical cyclone.[3] A few hours later, the JTWC would issue its first advisory on the system, designating it as Tropical Depression 21W.[4]

The next day, the JMA would upgrade the nascent depression to a tropical storm, naming it Haitang.[5] Later that day, the storm became better organized; however, its low-level circulation center (LLCC) would become fully exposed due to moderate vertical wind shear from nearby Typhoon Nesat, which prevented further strengthening.[6] Haitang would significantly slow down, meandering towards Vietnam at a speed of 3 knots (5.6 km/h; 3.5 mph).[7] However, in the night of September 26, Haitang would rapidly accelerate westwards, later making landfall near Hue, Vietnam.[8] Despite some bursts of convection, both land interaction and vertical wind shear would cause the system to weaken into a tropical depression, resulting in the JTWC issuing its last advisory on Haitang at 21:00 UTC that day.[9] The JMA would still track Haitang until it degenerated into a remnant low in Vietnam early on September 27.[10]

Preparations and impacts[edit]

Vietnam[edit]

The national carrier of Vietnam, Vietnam Airlines, would cancel 36 flights throughout September 26–27 due to the threat posed by the cyclone.[11] As Haitang impacted Vietnam, it would cause flash flooding throughout the nation's central provinces.[12] Waters in the Kiến Giang, Bo, and Huong rivers rose to record levels and in Hue City, low-lying areas were inundated, resulting in the city's residents using boats for transport.[13] Haitang would cause seven fatalities, all in Vietnam, and cause four others to be missing as well.[12][14] Haitang would damage 128 homes, also flooding around 5000 hectares of crops.[15]

Thailand[edit]

In Thailand, the remnants of Haitang would produce torrential rains throughout most of the nation, contributing to the 2011 Thailand floods.[16][17] The Thai Meteorological Department would advise people to refrain from going out to sea.[17]

See also[edit]

References[edit]

  1. ^ Joint Typhoon Warning Center. "JTWC — Tropical Cyclone Warning 211500 – Tropical Storm Nesat and Tropical Depression 31". Archived from the original on May 22, 2024. Retrieved September 24, 2011.
  2. ^ "JMA — Tropical Cyclone Warning 240000 – Tropical Depressions 31". Japan Meteorological Agency. Archived from the original on May 2, 2001. Retrieved September 24, 2011.
  3. ^ Joint Typhoon Warning Center. "JTWC — Tropical Cyclone Formation Alert — Tropical Depression 31". Archived from the original on April 30, 2001. Retrieved September 24, 2011.
  4. ^ Joint Typhoon Warning Center. "JTWC — Tropical Cyclone Advisory 01 – Tropical Storm Haitang". Archived from the original on April 30, 2001. Retrieved September 29, 2011.
  5. ^ "JMA — Tropical Cyclone Advisory 250000 – Tropical Storm Haitang". Japan Meteorological Agency. Archived from the original on May 22, 2024. Retrieved September 29, 2011.
  6. ^ Joint Typhoon Warning Center. "JTWC — Tropical Cyclone Advisory 04 – Tropical Storm Haitang". Archived from the original on May 22, 2024. Retrieved September 29, 2011.
  7. ^ Joint Typhoon Warning Center. "JTWC — Tropical Cyclone Advisory 06 – Tropical Storm Haitang". Archived from the original on May 22, 2024. Retrieved September 29, 2011.
  8. ^ "2011 West Pacific TCR" (PDF). Joint Typhoon Warning Center: 36.
  9. ^ Joint Typhoon Warning Center. "JTWC — Tropical Cyclone Advisory 10 – Tropical Storm Haitang". Archived from the original on May 22, 2024. Retrieved September 29, 2011.
  10. ^ "JMA — Tropical Cyclone Advisory 270600 – Tropical Storm Haitang". Japan Meteorological Agency. Archived from the original on May 22, 2024. Retrieved September 29, 2011.
  11. ^ "PRESS DIGEST - Vietnam newspapers - Sept 27". Reuters. September 26, 2011. Retrieved December 23, 2023.
  12. ^ a b "Tropical Cyclones bring Heavy Rains to the Far East | NASA Global Precipitation Measurement Mission". gpm.nasa.gov. Retrieved 2023-12-23.
  13. ^ "Tropical storm Haitang slams central Vietnam". Borneo Post Online. 2011-09-27. Retrieved 2023-12-22.
  14. ^ "TROPICAL CYCLONES IN 2011". www.hko.gov.hk. Retrieved 2023-12-22.
  15. ^ "Typhoon Nesat to strike central region tomorrow". Vietnamese Government. September 29, 2011 – via ReliefWeb.
  16. ^ "Thailand flood its most expensive in history; Western Caribbean disturbance develops | Category 6™". Weather Underground. Retrieved 2023-12-23.
  17. ^ a b Mail, Pattaya (2011-09-28). "Northeast, East and South to brace for Storm Haitang". Pattaya Mail. Retrieved 2023-12-23.