Southeast Asia Weather & Natural Hazards Today: Monday, November 9, 2026

Nov 9, 2026 · @Paul

By Paul Harrison, Orbis Weather

Central Vietnam faces the region’s most serious hazard on Monday: three days of very heavy rain from Hue to Quang Ngai, with flash floods and landslides possible. A cold air mass from China is bringing cooler, windy weather to northern Vietnam and upper Thailand and very heavy rain to southern Thailand, while a monsoon surge reaches Malaysia’s east coast and Sabah and four Indonesian provinces are under heavy-rain alerts.

Typhoon Cempaka is over the Philippine Sea south of Japan. The Philippine weather agency PAGASA does not expect it to directly affect weather in the Philippines, and forecasters expect it to turn northeast, away from Southeast Asia. This report is current to 7:00 a.m. Monday, November 9 in Bangkok, Hanoi and Jakarta (UTC+7), 8:00 a.m. in Manila, Singapore and Kuala Lumpur (UTC+8), and 7:00 p.m. Sunday, November 8 US Eastern time.

Key facts

Tropical cyclones

Typhoon Cempaka is the only active system in the region’s waters, and no agency expects it to reach Southeast Asian land.

PAGASA expected Cempaka to enter its monitoring area, known as PAR, between Sunday evening and Monday, then turn north-northeast and leave it by Monday afternoon or evening. JMA’s forecast takes it east toward Japan’s Ogasawara Islands by Wednesday. No tropical cyclone or disturbance was listed for the South China Sea, Bay of Bengal or Andaman Sea in the latest Joint Typhoon Warning Center outlooks.

Floods and heavy rain

Vietnam

Vietnam’s National Centre for Hydro-Meteorological Forecasting (NCHMF) rates the heavy-rain risk at level 1, its highest, and warns that rain may exceed 100 mm in three hours. Between 7:00 p.m. Sunday and 3:00 a.m. Monday (Hanoi time), Thanh Tan 1 station in Thanh Hoa recorded 266.6 mm and Nong Truong 15 in Nghe An 171.6 mm.

The agency warns of urban flooding, flash floods on small rivers and landslides on slopes, and expects the rain to ease from Thursday. A dispatch signed on November 7 by Deputy Prime Minister Ho Quoc Dung told Nghe An, Ha Tinh, Quang Tri, Hue, Da Nang, Quang Ngai, Gia Lai and Dak Lak to review evacuation plans and position rescue equipment. No deaths had been attributed to the new event in reports published by Sunday evening.

Thailand

The Thai Meteorological Department (TMD) forecasts heavy to very heavy rain across the south as a strong cold air mass strengthens easterly winds. Nakhon Si Thammarat, Songkhla, Pattani, Surat Thani, Phatthalung and Narathiwat face very heavy rain on Monday. TMD warns of flash floods, rapid runoff and mudslides, and of waves above 2 metres in thunderstorms in the Andaman Sea and Gulf of Thailand through Friday, November 13.

Malaysia

MetMalaysia director-general Mohd Hisham Mohd Anip said “a monsoon surge is expected to affect the country from Nov 9 to 11.” An alert-level continuous-rain warning runs until Wednesday for much of Kelantan, all of Terengganu, and Kuantan, Pekan and Rompin in Pahang, and from Monday for Kudat and Sandakan in Sabah. On Sunday afternoon, flash floods hit Taman Sri Muda and Kampung Baru Hicom in Shah Alam, Selangor; the Selangor Fire and Rescue Department said no evacuations were carried out.

Country-by-country weather today

Earthquakes

The US Geological Survey (USGS) recorded five earthquakes of magnitude 4.4 or greater in the region in the 48 hours to Monday morning, none above magnitude 4.9.

Tsunami status: USGS did not flag a tsunami for any of these events, and no tsunami warning was reported.

Volcanoes

Mayon in the Philippines is the volcano to watch, after a moderate eruption on October 30 led PHIVOLCS to raise its alert. Philippine alert levels run from 0 to 5; Indonesia’s run from Level I (normal) to Level IV (Awas, danger).

Haze, fires and air quality

The ASEAN Specialised Meteorological Centre (ASMC) downgraded the southern ASEAN region to haze Alert Level 1 in its update of November 5, with few to isolated hotspots (satellite-detected fires) in southern Sumatra, Kalimantan, Sulawesi and eastern Vietnam. It still observed moderate to dense smoke plumes over southeastern Sulawesi and southern Kalimantan and Papua, and expected the situation to remain subdued.

What to watch over the next few days

• Central Vietnam, Monday to Wednesday: the heaviest rain shifts to Hue, Da Nang and eastern Quang Ngai, where river and flash flooding are the main risks.
• Typhoon Cempaka: JMA forecasts it to peak as a “very strong” typhoon (about 155 km/h sustained) by early Tuesday before moving east. PAGASA expects very rough seas off Northern Luzon from Tuesday.
• Malaysia: rain from the monsoon surge is forecast to persist on the peninsula’s east coast and in eastern Sabah through midweek.
• Thailand: cooler, windy weather in the upper country through Friday; a westerly trough may bring thunderstorms, hail and gusty winds to the upper North on November 11–12.
• Mayon: PHIVOLCS is tracking indicators such as RSAM, a measure of seismic energy, to decide whether to raise the alert further.

About this article

This article summarises official bulletins and news reports from national weather and disaster agencies; it is not an official warning, and readers should follow their national agency for decisions. Wind speeds were converted from knots (1 knot = 1.852 km/h) and distances from nautical miles, then rounded. Volcano alert levels carry the date of the most recent status found, and some predate this report by several weeks. Rainfall forecasts and warnings change quickly, so later bulletins may supersede the figures here.

Frequently asked questions

Will Typhoon Cempaka hit the Philippines? PAGASA says Cempaka is not expected to directly affect weather or sea conditions in the Philippines. Forecasters expect it to turn north-northeast and leave the Philippine monitoring area quickly. Sea conditions off Northern Luzon are still expected to worsen because of the northeast monsoon.

What is driving the weather in northern and central Vietnam? A cold air mass from China reached northern Vietnam overnight Sunday into Monday, and forecasters expect very heavy rain in the centre for three consecutive days. NCHMF forecasts lows of 15–18°C in the north and north-central region during the cold spell, and below 12°C in the high mountains.

What do Indonesia’s “Siaga” and “Waspada” warnings mean? They are levels in BMKG’s early-warning system. “Waspada” (watch) means moderate to heavy rain is possible; “Siaga” (alert) means heavy to very heavy rain with a potential for floods, flash floods and landslides.

Why do agencies give different wind speeds for Cempaka? Each agency issues its estimate at a different time, and they measure wind differently. JMA and PAGASA report winds averaged over 10 minutes, while the US Joint Typhoon Warning Center uses a one-minute average, which usually gives a higher figure for the same storm.

Sources

• JMA: Typhoon Cempaka specifications (TC2638)
• JTWC: Significant Tropical Weather Advisory, Western Pacific
• JTWC: Significant Tropical Weather Advisory, Indian Ocean
• PAGASA homepage and forecasts
• PAGASA Tropical Cyclone Advisory
• Philstar: ‘Cempaka’ expected to intensify into typhoon before entering PAR
• NCHMF: Heavy-rain bulletin, southern Nghe An to Da Nang and Quang Ngai to Dak Lak
• NCHMF: Northeast monsoon (cold air) bulletin
• NCHMF homepage and warnings
• Dan Tri: North turns cold, central region very heavy rain
• NetNewsLedger: Vietnam orders flood preparations as central coast faces extreme rain
• The Nation: Rain eases in upper Thailand with heavy rain forecast in southern areas
• The Nation: Cooler weather forecast for upper Thailand as South faces heavy rain
• Malay Mail: MetMalaysia forecasts continuous rain in Kelantan, Terengganu
• Media Selangor: Continuous rain expected in four states until Wednesday
• Malay Mail: Flash floods in Taman Sri Muda, no displacement reported
• Meteorological Service Singapore: Fortnightly weather outlook
• Kontan: BMKG early warning for November 9
• Sinata.id: BMKG warns of heavy rain, high waves and coastal flooding
• USGS earthquake catalogue query
• Manila Times: Mayon continues to show heightened volcanic activity
• Manila Times: PHIVOLCS warns of possible Mayon Alert Level 4 escalation
• Smithsonian/USGS Weekly Volcanic Activity Report
• CNBC Indonesia: Semeru erupts, 1,000 m ash column
• Antara: 11 Indonesian volcanoes that erupted in 2026
• ASEAN Specialised Meteorological Centre