On August 22, according to Vietnam Air Traffic Management Corporation (VATM), storm No. 4 (NARRA) is operating in the Northern Gulf of Tonkin with intensity level 8, gusts level 10, moving slowly and still developing complicatedly.
The typhoon circulation combined with the tropical convergence zone and strongly developing convective cloud areas is directly affecting the Northern FIR region of Vietnam (fly notice zone).
At 7:00 AM on August 22, the storm center was located in sub-area 2 under the control of the Hanoi Long-Dang Control Center (ACC Hanoi), about 85km from Van Don airport, 165km from Cat Bi, 250km from Noi Bai and 325km from Tho Xuan.
Forecast for the next 24 hours, the storm will move in a South-Southwest direction at a speed of about 3 km/h over the Northern Gulf area, with little change in intensity. After that, the storm will continue to move slowly, changing direction to Southeast then East-Northeast and is likely to gradually weaken into a tropical depression in the next 72-120 hours.
VATM said that besides the storm's circulation, the tropical convergence zone with an axis of about 18-21°N connected to the storm, combined with wind convergence, is creating conditions for the formation of strong convective cloud areas in the northern sky.
From now until August 24, in sub-zones 1 and 2 under the management of ACC Hanoi, convective clouds, thunderstorms and many dangerous weather phenomena are forecast to appear.
According to VATM, convective clouds can develop rapidly, changing weather conditions in a short time and affecting the organization and operation of flights in the area.
Along with the diễn biến of the storm, the weather at Van Don, Cat Bi and Noi Bai airports continues to have unfavorable factors for exploitation activities.
In Van Don, from August 22nd, there will be rain, showers, and sometimes thunderstorms. In thunderstorms, the lowest visibility may decrease to 2-3km; from the evening of August 22nd, visibility may sometimes decrease to 1.5-3km.
In Cat Bi, thunderstorms can reduce visibility to 1.5-3km. In the following periods, thunderstorms will still persist.
In Noi Bai, on August 22, visibility in thunderstorms may decrease to 2-4km. The weather in the following days will continue to have rain, showers and thunderstorms.
Faced with the developments of storm No. 4, VATM continues to direct agencies and units to strictly maintain duty regimes, regularly update storm developments and actual weather conditions, and proactively implement appropriate response measures.
Air traffic control facilities under VATM implement a periodic reporting regime at 6 am and 12 pm daily, update weather conditions, developments of air traffic control operations and related issues, and send them to the General Corporation's Steering Committee for Natural Disaster Prevention and Control and Search and Rescue for summarization and reporting to the Civil Aviation Authority of Vietnam and the Ministry of Construction.
