FLASH UPDATE #1 – Southwest Monsoon, Tropical Cyclones 91W (BUTCHOY) & 92W (CARINA)
Countries under monitoring: Philippines, Viet Nam
OVERVIEW: According to PAGASA, on 19 July at 1900H UTC+7, INVEST 91W west of Batangas and INVEST 92W east of Eastern Visayas developed into Tropical Depressions BUTCHOY (91W) and CARINA (92W), respectively. At 0200H today, the centre of TC 91W was estimated based on all available data at 615 km West of Tanauan City, Batangas or 525 km West of Subic Bay (14.5°N, 115.4°E). The centre of 92W was estimated based on all available data at 645 km East of Virac, Catanduanes (14.6°N, 130.1°E). Meanwhile, the Southwest Monsoon which has been causing widespread flooding in Mindanao since 11 July, continues to affect the western parts of Southern Luzon, Visayas, and Mindanao.
MOVEMENT & INTENSITY: According to PAGASA’s update today, 20 July at 0200H UTC+7:
- TC 91W – maximum sustained winds of 55 km/h near the centre and gustiness of up to 70 km/h. It is moving West Northwestward at 20 km/h.
- TC 92W – with maximum sustained winds of 55 km/h near the center and gustiness of up to 70 km/h. It is moving Northwestward at 30 km/h.
FORECAST:
According to PAGASA Tropical Cyclone Bulletin 1 for TC 91W and TC 92W:
- TC 91W – is forecast to move generally west northwestward until 20 July before turning more north northwestward beginning on Sunday (21 July). On the track forecast, this tropical depression may exit the Philippine Area of Responsibility within the next 12 hours. Furthermore, a landfall scenario over Hainan, China is likely by late Sunday or early Monday (22 July).
- TC 92W – is forecast to move generally northwestward until 21 July. It is then forecast to decelerate while turning north northwestward on 22 July before accelerating northward over the Philippine Sea towards the Ryukyu archipelago from 23 July onwards. In general, TC 92W will generally have a mainly offshore path over the next 5 days and remain far from the Philippine landmass. It is forecast to slowly intensify and may reach tropical storm category by 21 July. Beginning on 22 July, TC 92W will likely intensify further at a faster rate, eventually reaching typhoon category on 23 July.
According to NHCMF update today at 0200H UTC+7, in the next 24-48 hours, TC 91W is forecast to be at the North East Sea areas on 21 July and in the sea north of Hoang Sa archipelago by 22 July, about 160 km East Southeast of Hainan, China.
HAZARDS:
Philippines
- Heavy Rainfall – According to PAGASA, the Southwest Monsoon currently enhanced by TC 91W will also be enhanced by 92W beginning on 21 July, resulting in moderate to heavy rains over the western portion of Luzon over the next 3 days:
July 20: Southwest Monsoon will bring moderate to heavy rains (50-100 mm) over Northern Palawan and Occidental Mindoro.
July 21: Moderate to heavy rains (50-100 mm) are possible over Zambales, Bataan, Occidental Mindoro, and Northern Palawan
July 22: moderate to heavy rains (50-100 mm) remain possible over Ilocos Region, Zambales, Bataan, Northern Palawan, and Occidental Mindoro
- TCWS – No Tropical Cyclone Wind Signal is currently in effect (PAGASA).
Viet Nam
- Strong Wind & Rough Seas – According to NHCMF, heavy showers and thunderstorms with strong winds of level 6-7, then increasing to level 8 and gusting up to level 10, cause very rough seas in the eastern area of the North East Sea.
IMPACTS: On 19 July, 0700H UTC+7, Philippines’ NDRRMC released the situation report on the widespread flooding and landslides from the combined effects of the Southwest Monsoon and 91W (as INVEST/Low Pressure Area):
- 573K affected population (118K families) in 7 regions, 17 provinces, 53 cities/municipalities
- 349K displacements; 53 evacuation centres have been activated
- 7 fatalities, 2 injuries, 1 missing
- 133 damaged houses (80 partially, 53 totally)
- 71 road sections, 5 bridge sections, and 1 seaport affected
- 8 cities/municipalities with interrupted power supply (50% restored); 2 with interrupted water supply, 1 with interrupted communication lines (restored)
- 310 hectares of crops have been totally damaged
- About 364K USD cost of damages
PREPAREDNESS AND RESPONSE:
- The Philippines’ NDRRMC-OCD is on ALERT Status BLUE for the combined effects of the Southwest Monsoon and 91W (as low pressure area).
- NDRRMC continues to monitor the situation, disseminate advisories, and coordinate with OCDROs and NDRRMC Member-Agencies.
- The NDRRMC-OCD and relevant authorities has ready standby funds and prepositioned relief stockpiles, emergency telecommunications equipment, and transportation assets.
- Search, Rescue, and Retrieval (SRR) teams, debris clearing operations units, uniformed personnel, and emergency response manpower have been mobilised and on standby for emergencies.
- PAGASA and NHCMF continue to monitor the weather situation and provide weather updates and early warning advisories to all stakeholders. NDRRMC Philippines and VDDMA Viet Nam closely monitor the updates and conduct close coordination and preparedness and response measures related to the development of these weather systems.
The AHA Centre will continue to monitor for further developments and issue necessary updates.
DATA SOURCES
ASEAN Disaster Monitoring & Response System (DMRS), ASEAN Disaster Information Network (ADINet); Pacific Disaster Center (PDC Global); ASEAN Specialised Meteorological Centre (ASMC);
Philippines: NDRRMC, PAGASA;
Viet Nam: VDDMA, NHCMF;
Verified news media agencies;
