Latest forecast on the path of typhoon Noru

On the afternoon of September 26, Mr. Nguyen Van Huong - Head of Weather Forecast Department, National Center for Hydro-Meteorological Forecasting, answered reporterson typhoon Noru forecast.

- How does the meteorological agency assess storm Noru?

- Considering the intensity of the storm when it hit the coast of Vietnam, Noru was one of the strongest storms in the past 20 years.

Before making landfall on the eastern part of Luzon Island in the Philippines, international meteorological agencies such as Japan assessed the storm to be level 15 (167-183 km/h), gusting above level 17 (over 200 km/h).

The storm is moving relatively fast, averaging 20-25 km/h and straight, so early this morning it crossed Luzon Island into the East Sea, becoming the fourth storm in this area this year. Because the storm is moving fast, this morning the National Center for Hydro-Meteorological Forecasting immediately issued an emergency storm warning (applicable to storms near the coast) instead of a storm warning in the East Sea according to procedure.

Mr. Nguyen Van Huong, Head of Weather Forecast Department, National Center for Hydro-Meteorological Forecasting, talks about storm Noru, afternoon of September 26. Photo:Household

- Where will the storm make landfall and what will its intensity be?

- The forecasts of domestic and international stations on the direction of movement in 24, 48, 72 hours are relatively consistent, mainly in a westerly direction, making landfall in the provinces from Thua Thien Hue to Binh Dinh. The storm has lost its intensity after entering the Philippines but is in the process of strengthening again, reaching its strongest intensity in the East Sea when passing south of the Hoang Sa archipelago, level 13-14, gusting to level 17.

However, the intensity and time of the storm's landing are different between stations. Specifically, two international stations said the storm will make landfall in Vietnam on the morning of September 28, with the Japanese station saying it will be level 13-14; the US Navy station saying it will be level 15-16. Meanwhile, Hong Kong radio said the storm will make landfall in the early morning of September 28, with a strength of level 14-15.

We estimate that the storm will begin to affect the mainland from the evening of September 27. When entering the coastal waters, the storm will maintain a level 13 wind speed (134-149 km/h), and when affecting the mainland, it will be between level 12-13, gusting to level 14.

Forecast of the path and affected area of ​​storm Noru at 4:00 p.m. on September 26. Photo:NCHMF

- Why did storm Noru intensify as it approached the central coast, while most other storms lost their intensity?

- When it made landfall in the Philippines, due to friction with the ground, the moisture supply was reduced, so the intensity of typhoon Noru decreased. However, when it reached the East Sea, the typhoon was given more heat and momentum.

Thermal forces are high sea surface temperature, approximately 31 degrees Celsius, high humidity. The driving force to create the vortex is the southwest wind below and the northeast wind above. These factors make the storm maintain its strong intensity when approaching the mainland of Vietnam.

- So what kind of rain and wind will the storm bring to the Central region?

- We divide the impact into two parts. First is the impact on the sea, the northern and central areas of the East Sea (the area where the storm's center passes) have strong winds of level 8-9, the area near the storm's center has strong winds of level 12-13 and as the storm intensifies, there will be strong winds of level 13-14, gusting to level 16. The southern part of the East Sea, the Gulf of Tonkin also has strong winds of level 6-7, gusting to level 8-9, waves 3-4 m high. Thus, it can be said that under the impact of storm Noru, most of the East Sea is rough.

From tomorrow afternoon, off the coast of the provinces from Quang Binh to Ninh Thuan, strong winds of level 8-9 will begin to appear, then increase to level 10-11, near the storm center, strong winds of level 12-14, gusts of level 17, waves 8-10 m high. From tomorrow evening and night, coastal waters from Thua Thien Hue to Binh Dinh will have waves 3-5 m high, near the storm center 6-8 m. Areas from Quang Binh to Quang Ngai need to be on guard against rising water levels of 1-1.5 m causing flooding in low-lying areas along the coast and river mouths.

The second is the impact on land. It is forecasted that from the morning of September 28, the coastal area from Quang Tri to Ninh Thuan will have winds of level 6, then increase to level 7-8, gusting to level 9-10. The coastal area from Da Nang, Quang Nam, Quang Ngai, Binh Dinh will have strong winds of level 9-10 from early morning of September 28, the area near the storm center will have winds of level 12-13, gusting to level 14-15.

Inland areas, the wind is strong at level 8-9, gusting to level 12-13; on September 28, Kon Tum and Gia Lai had winds gradually increasing to level 6, then increasing to level 7-8, in some places level 9, gusting to level 11. I assess that the wind level in Kon Tum and Gia Lai is relatively strong, and will affect residential buildings and industrial crops.

Heavy rain from September 27 to September 28, Quang Tri, Thua Thien Hue, Da Nang, Quang Nam, Quang Ngai, Kon Tum areas have very heavy rain with common amount of 250-350 mm, some places over 400 mm. Quang Binh, Binh Dinh, Gia Lai areas have rain of 100-200 mm, some places over 300 mm. From September 28, heavy rain tends to expand to the North Central region and the Southern Delta of the North.

- How is the flood forecast after the storm, sir?

We forecast two flood scenarios. First, heavy rain over 300 mm, with a high possibility, rivers in Quang Binh, Quang Tri, Quang Nam will have flood warning level 1-2; rivers in Binh Dinh, Kon Tum, Gia Lai will have flood warning level 2-3, possibly above warning level 3; rivers in Thua Thien Hue will be around warning level 1.

The second scenario is if heavy rain is over 400 mm, flood peaks on rivers in the Central Central region and the Northern Central Highlands will generally be at alert level 2-3, possibly above alert level 3. The Huong River in Hue is around alert level 2. The Central Central region and the Northern Central Highlands provinces with about 60 districts will be at risk of flooding.

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

-Two storms had similar intensity and direction to Noru. The first was storm Xangsane in September 2006, which made landfall in Da Nang - Quang Nam, with maximum winds of 136 km/h. The storm caused 5 days of rain with an amount of 200-300 mm in the provinces from Nghe An to Quang Ngai, 300-400 mm in Quang Binh to Thua Thien Hue. The consequences were 76 people dead and missing, more than 500 injured, nearly 350,000 houses collapsed and damaged, and nearly 1,000 ships sunk.

The second was typhoon Ketsana in late September 2009, the eye of the storm hit Quang Nam - Quang Ngai, causing 120-270 mm of rain in Quang Binh province, 200-400 mm in Quang Tri, Quang Ngai, Gia Lai, Kon Tum provinces and 400-600 mm in the provinces from Thua Thien Hue to Quang Ngai. The storm and flood claimed 163 lives, left 11 people missing, more than 21,000 houses collapsed, nearly 260,000 others were severely damaged. Material damage was estimated at 14,000 billion VND.

At 5:00 p.m. on September 26, the National Center for Hydro-Meteorological Forecasting said that storm Noru had increased by half a level compared to 2:00 p.m. Specifically, the storm was in the eastern and central waters of the East Sea, about 580 km from the Hoang Sa archipelago, with the strongest wind speed of 149 km/h, level 12-13, gusting to level 15. It is forecasted that in the next 24 hours, the storm will move westward at a speed of 20-25 km/h and will tend to strengthen.

The agency has adjusted the disaster risk level. Thua Thien Hue was added to Da Nang, Quang Nam, Quang Ngai, Binh Dinh to face level 4 risk, Quang Tri, Phu Yen, Kon Tum, Gia Lai to level 3 (highest is level 5 - disaster).