Latest forecast on the path of Typhoon Noru

On the afternoon of September 26th, Mr. Nguyen Van Huong, Head of the Weather Forecasting Department at the National Center for Meteorological and Hydrological Forecasting, answered questions from reporters.Regarding the forecast for Typhoon Noru.

- What is the meteorological agency's assessment of Typhoon Noru?

- Considering the intensity of the storm when it made landfall on the Vietnamese coast, Noru was one of the strongest in the last 20 years.

Before making landfall on the eastern part of Luzon Island in the Philippines, international meteorological agencies such as Japan predicted the typhoon would reach Category 15 (167-183 km/h), with gusts exceeding Category 17 (over 200 km/h).

The storm moved relatively quickly, averaging 20-25 km/h and in a straight line, so it crossed Luzon Island into the South China Sea early this morning, becoming the fourth storm in the region this year. Because of its rapid movement, the National Center for Meteorological and Hydrological Forecasting issued an emergency storm warning (applicable to storms near the coast) instead of the standard South China Sea storm warning.

Mr. Nguyen Van Huong, Head of the Weather Forecasting Department, National Center for Meteorological and Hydrological Forecasting, speaks about Typhoon Noru on the afternoon of September 26. Photo:Gia Chinh

- Where will the storm make landfall, and how strong will it be?

- Domestic and international weather forecasts regarding the storm's movement over the next 24, 48, and 72 hours are relatively consistent, mainly heading west, making landfall in the provinces from Thua Thien Hue to Binh Dinh. After entering the Philippines, the storm weakened but is in the process of strengthening again, reaching its strongest intensity in the East Sea when passing south of the Hoang Sa archipelago, at level 13-14, with gusts up to level 17.

However, the intensity and timing of the storm's landfall are differing among various weather stations. Specifically, two international stations predict the storm will make landfall in Vietnam on the morning of September 28th, with an intensity of level 13-14 according to the Japanese station and level 15-16 according to the US Navy station. Meanwhile, the Hong Kong station predicts the storm will make landfall in the early morning of September 28th, with a strength of level 14-15.

We predict the storm will begin affecting the mainland from the evening of September 27th. When it enters the coastal waters, the storm will maintain a speed of approximately level 13 (134-149 km/h), and when it affects the mainland, it will be somewhere between level 12-13, with gusts up to level 14.

Forecast of the path and affected areas of Typhoon Noru at 4 PM on September 26th. Photo:NCHMF

- Why did Typhoon Noru intensify as it approached the central coast, while most other typhoons weakened?

- Upon making landfall in the Philippines, friction with the land reduced the moisture supply, causing Typhoon Noru to weaken. However, as it moved into the South China Sea, the typhoon gained additional heat and momentum.

The thermal forces are high sea surface temperatures, approximately 31 degrees Celsius, and high humidity. The driving forces creating the vortex are southwesterly winds from below and northeasterly winds from above. These factors allow the storm to maintain its strong intensity as it approaches the Vietnamese mainland.

So, what kind of rain and wind will the storm bring to Central Vietnam?

- We've divided the impact into two parts. Firstly, the impact at sea: the northern and central areas of the South China Sea (the area where the storm's center passes through) will experience strong winds of force 8-9, with winds near the storm's center reaching force 12-13, and as the storm intensifies, winds will reach force 13-14, gusting to force 16. The southern part of the South China Sea and the Gulf of Tonkin will also experience strong winds of force 6-7, gusting to force 8-9, with waves reaching 3-4 meters in height. Therefore, it can be said that under the influence of Typhoon Noru, most of the South China Sea will experience rough seas.

From noon tomorrow, strong winds of force 8-9 will begin off the coast of provinces from Quang Binh to Ninh Thuan, later increasing to force 10-11, with winds near the storm's center reaching force 12-14, gusting to force 17, and sea waves reaching 8-10 meters. From tomorrow evening and night, sea waves along the coast from Thua Thien Hue to Binh Dinh will reach 3-5 meters, and 6-8 meters near the storm's center. Areas from Quang Binh to Quang Ngai should be wary of storm surges of 1-1.5 meters causing flooding in low-lying coastal areas and river mouths.

Secondly, there are the impacts on land. Forecasts indicate that from the morning of September 28th, coastal areas from Quang Tri to Ninh Thuan will experience winds of level 6, later increasing to levels 7-8, with gusts of level 9-10. Coastal areas of Da Nang, Quang Nam, Quang Ngai, and Binh Dinh will experience strong winds of level 9-10 from early morning on September 28th, with areas near the storm's center experiencing winds of level 12-13, and gusts of level 14-15.

Further inland areas experienced strong winds of force 8-9, gusting to force 12-13; Kon Tum and Gia Lai on September 28th saw winds gradually increase to force 6, then to force 7-8, with some areas reaching force 9, gusting to force 11. I assess that such wind speeds in Kon Tum and Gia Lai are relatively strong and will affect residential buildings and industrial crops.

Heavy rain from September 27th to 28th will bring very heavy rainfall to Quang Tri, Thua Thien Hue, Da Nang, Quang Nam, Quang Ngai, and Kon Tum, with amounts generally ranging from 250-350 mm, and exceeding 400 mm in some areas. Quang Binh, Binh Dinh, and Gia Lai will receive 100-200 mm of rain, with some areas exceeding 300 mm. From September 28th onwards, heavy rain is expected to spread to the North Central region and the southern part of the Northern Delta.

- What are the forecasts for rain and flooding after the storm, sir?

We forecast two flood scenarios. Firstly, heavy rainfall exceeding 300 mm is highly likely, resulting in flood warning levels 1-2 in Quang Binh, Quang Tri, and Quang Nam provinces; flood warning levels 2-3 in Binh Dinh, Kon Tum, and Gia Lai provinces, possibly exceeding level 3; and river levels around level 1 in Thua Thien Hue province.

The second scenario is that if rainfall exceeds 400 mm, flood peaks on rivers in Central Vietnam and the Northern Central Highlands will generally reach alarm levels 2-3, possibly exceeding alarm level 3. The Perfume River in Hue will be around alarm level 2. Approximately 60 districts in the Central Vietnam and Northern Central Highlands provinces will be at risk of flooding.

- You said Noru was one of the strongest typhoons in the last 20 years. So, in the past, what typhoons were as strong as Noru and what kind of damage did they cause?

ButTwo storms with similar intensity and trajectory to Noru have occurred. The first was Typhoon Xangsane in September 2006, which made landfall in Da Nang and Quang Nam, with maximum wind speeds of 136 km/h. The storm caused rain for five days, with 200-300 mm in provinces from Nghe An to Quang Ngai and 300-400 mm in Quang Binh to Thua Thien Hue. The consequences included 76 deaths and disappearances, over 500 injuries, nearly 350,000 houses destroyed or damaged, and nearly 1,000 boats sunk.

Secondly, Typhoon Ketsana struck Quang Nam and Quang Ngai provinces in late September 2009, causing rainfall of 120-270 mm in Quang Binh province, 200-400 mm in Quang Tri, Quang Ngai, Gia Lai, and Kon Tum provinces, and 400-600 mm in provinces from Thua Thien Hue to Quang Ngai. The storm claimed 163 lives, left 11 missing, destroyed over 21,000 houses, and severely damaged nearly 260,000 others. Material damage was estimated at 14 trillion VND.

At 5 PM on September 26th, the National Center for Meteorological and Hydrological Forecasting announced that Typhoon Noru had intensified by half a level compared to 2 PM. Specifically, the typhoon is currently located in the eastern and central parts of the South China Sea, approximately 580 km from the Hoang Sa (Paracel) Islands, with maximum wind speeds of 149 km/h (level 12-13), gusting to level 15. The forecast indicates that over the next 24 hours, the typhoon will move westward at a speed of 20-25 km/h and is expected to strengthen further.

The agency has adjusted the disaster risk levels. Thua Thien Hue, along with Da Nang, Quang Nam, Quang Ngai, and Binh Dinh, is now at risk level 4, while Quang Tri, Phu Yen, Kon Tum, and Gia Lai are at level 3 (the highest level being level 5 - a catastrophe).

Gia Chinh