Singapore Weather & Natural Hazards This Week, October 19, 2026

By Paul Harrison, Orbis Weather

At a glance

Smoke haze from fires in Kalimantan remains the main hazard for Singapore this week, though a shift in the winds brought some relief on Sunday, October 18.

• Air quality: the 24-hour PSI was 109 to 192 (Unhealthy) at 6pm on Sunday, October 18, down from a season-high 230 in the west at 10am that day. The NEA forecast for Monday, October 19 is 101 to 190 (Unhealthy). The NEA says winds may turn east-southeasterly from Tuesday night, which may bring Kalimantan smoke back overnight.
• Weather: the Meteorological Service Singapore (MSS) forecasts afternoon thundery showers from Monday to Thursday, with highs of 34°C (93°F) and lows of 25°C (77°F). Rainfall for the second half of October is forecast to be below average over most of the island.
• Measures in force: the Haze Subsidy Scheme for haze-related clinic treatment has run since October 12. N95 masks are being handed out to vulnerable Singaporeans. Schools and educational institutions in Johor are closed for another five days from October 19.
• Tropics: no tropical cyclone or disturbance is in or near the South China Sea. None has any bearing on Singapore.
• Earthquakes: the US Geological Survey (USGS) recorded no earthquake of magnitude 4.5 or greater in the region around Singapore since October 12.
• Volcanoes: Krakatau in the Sunda Strait, and Merapi and Semeru on Java, are at Alert Level 3 of 4. Marapi on Sumatra is at Level 2. None is reported to affect flights at Changi.

The Meteorological Service Singapore and the National Environment Agency (NEA) issue the official forecasts, warnings and health advisories. Check haze.gov.sg, the MSS website or the myENV app before making plans.

This week’s weather

Hot afternoons with thundery showers are the pattern for the first four days of the week. The MSS four-day outlook, updated at 4.55pm SGT on Sunday, October 18, gives the same forecast for each day.

The official day-by-day forecast covers only these four days. There is no official daily forecast yet for Friday, October 23 to Sunday, October 25. The MSS fortnightly outlook gives the general pattern for those days (below).

For Monday, the MSS 24-hour forecast expects thundery showers mainly over northern and western Singapore in the afternoon. It gives a high of 34°C (93°F), a low of 25°C (77°F), relative humidity of 60% to 95% and southeasterly winds of 10–20 km/h (6–12 mph).

Observations so far today. As of 6am SGT on Monday, October 19, MSS reported:

• Highest temperature: 30.1°C (86.2°F) at Pasir Panjang Terminal, 2am.
• Lowest temperature: 25.2°C (77.4°F) at Tengah, 5.59am.
• Highest rainfall: 0.0 mm (0.0 in).
• Highest wind: easterly 12.0 km/h (7.5 mph) at Semakau Island, 12.05am.

What is driving the weather

The Southwest Monsoon is still in place. The MSS fortnightly outlook for October 16 to November 1, 2026 (page dated October 17) expects it to continue through the fortnight. Winds will blow mainly from the southeast or southwest, and may turn light and variable on a few days.

MSS expects localised, short-duration thundery showers in the afternoon on most days. Total rainfall for the second half of October is forecast to be below average over most of the island. Daily highs are likely to range from 33°C (91°F) to 35°C (95°F), and could slightly exceed 35°C on a few days. Some nights may stay above 27°C (81°F).

The first half of October was largely dry, with well below average rainfall. Rainfall around Punggol was about 94% below average. The wettest day was October 1, when 60.4 mm (2.38 in) fell at Nanyang Avenue. The hottest was 34.9°C (94.8°F) at Pulau Ubin on October 6.

For comparison, the MSS October averages for 1991 to 2020 are:

The ASEAN Specialised Meteorological Centre (ASMC) expects the Southwest Monsoon to gradually give way to inter-monsoon conditions towards the end of October. It predicts below-normal October rainfall for much of the Maritime Continent, and expects El Niño to strengthen in October and November 2026. Its subseasonal outlook for October 12 to 25 predicts drier than usual conditions over most of the southern ASEAN region.

Haze and air quality

Air quality remains in the Unhealthy range, but improved on Sunday afternoon as winds turned to blow from the south. The NEA expects a 24-hour PSI of 101 to 190 (Unhealthy) on Monday, October 19. It warns that winds may turn east-southeasterly from Tuesday night, which may bring smoke haze from Kalimantan back towards Singapore overnight.

The latest readings are from the NEA update at 6pm SGT on Sunday, October 18; Monday morning’s readings had not yet been published. The 10am readings from the same day show how high levels were earlier that day.

At 6pm the 24-hour PSI was Unhealthy across Singapore. It was highest in the west at 192 and lowest in the north at 109. At 10am the west had reached 230, a season high in the Very Unhealthy range, while the other regions read 130 to 187.

How the past week went

The haze worsened sharply from Wednesday, October 14, when dense smoke from Kalimantan arrived on southeasterly winds. MSS says one-hour PM2.5 entered the Very High band (251 µg/m³ or more) at 2pm that day, and the 24-hour PSI became Very Unhealthy at 9pm. The highest one-hour PM2.5 of the year, 288 µg/m³, was recorded in the west at 3pm on October 14, The Straits Times reported.

On Saturday, October 17, one-hour PM2.5 in the west reached 243 µg/m³ at 2pm before thundery showers kept it below the Very High band. Malay Mail, citing AsiaOne, reported on October 18 that Singapore had had 14 straight days of unhealthy air since October 5. It called this the longest such run since 2015.

For context, the 24-hour PSI first reached the Unhealthy range this year on September 4. Before this week, the 2026 peak was 192 in the central region on October 9.

Fires and the regional picture

The ASMC has kept Alert Level 3, its highest, for the southern ASEAN region since August 26, 2026. Its latest regional summary, last modified on October 16, reports widespread hotspots in Kalimantan and Sumatra. Air quality stations there reported Unhealthy to Hazardous levels. ASMC data cited by AsiaOne show 110 hotspots in Kalimantan and 11 in Sumatra on October 17.

The ASMC expects the southern ASEAN region to stay mostly dry over the next few days. It forecasts showers over Peninsular Malaysia, northern and central Sumatra and parts of Borneo. It says the hotspot and smoke haze situation is likely to stay elevated, with a continued risk of severe transboundary haze.

On the IQAir live ranking of major cities, read at about 7am SGT on Monday, October 19, Singapore was ninth with a US AQI of 158. Kuala Lumpur was third at 180 and Kuching seventh at 160. Johor Bahru was not listed. The US AQI used by IQAir is a different scale from Singapore’s PSI.

Health advice for Monday, October 19

The NEA bases its advice on the Unhealthy PSI forecast. For immediate outdoor plans, it asks people to check the latest one-hour PM2.5 reading.

When one-hour PM2.5 is in the High band, the NEA advised on October 17 that vulnerable groups avoid all outdoor activity for the next hour, and said they may wear a mask.

Measures in place

• Haze Subsidy Scheme: activated on Monday, October 12, for the first time since 2015, AFP reported. Treatment is capped at S$10 for most eligible Singaporeans and S$5 for seniors aged 67 and above. It covers allergic rhinitis, asthma, bronchitis, conjunctivitis, chronic obstructive pulmonary disease, upper respiratory tract infection and their complications.
• Masks: N95 masks have been distributed to vulnerable Singaporeans since October 14 through community clubs and 37 vending machines, Minister for Sustainability and the Environment Grace Fu said on October 16. About 10% of those eligible had collected masks by then.
• Enforcement: the NEA will send Preventive Measure Notices under the Transboundary Haze Pollution Act to seven companies whose land fires contributed to the haze, Ms Fu said. She also offered Indonesia firefighting and cloud-seeding help.
• Schools: a pupil quoted by AsiaOne on October 18 said recess had moved indoors and outdoor PE had stopped. No closure of Singapore schools has been reported.
• Johor: schools and educational institutions across Johor are closed for another five days from Monday, October 19, the state education committee chairman said on October 18. Home-based learning continues. Air Pollutant Index readings “remain at concerning levels, with no significant improvement”, he said.
• Flights: Firefly cancelled flights from Sultan Abdul Aziz Shah Airport near Kuala Lumpur to Seletar from Saturday, October 10, as a precaution. Reports dated October 12 and 13 differ on whether the cancellations ran to October 12 or 13.

Ms Fu said on October 16 that the haze may persist for some time and that air quality may reach hazardous levels. She said the inter-monsoon period is expected from late October or early November, and the Northeast Monsoon from around early December should blow haze away from Singapore.

Rain and thunderstorms

No heavy rain warning was in force early on Monday, October 19, and the rain expected this week is the short afternoon kind. MSS forecasts afternoon thundery showers on each day from Monday to Thursday. On Monday they are expected mainly over northern and western Singapore.

The MSS fortnightly outlook describes the showers as localised and short-duration, falling over parts of the island in the afternoon on most days. It forecasts below-average rainfall for the second half of October over most of the island. The ASMC rainfall outlook also expects the southern ASEAN region to remain mostly dry over the next few days.

Showers this week matter for air quality as well as for travel. The NEA said thundery showers on Saturday, October 17 kept one-hour PM2.5 in the west below the Very High band. It reported showers over parts of Singapore on October 15, 16 and 17.

No flash floods, fallen trees or lightning incidents were reported in Singapore in the past week. The last notable downpour was on October 1, when regional wind convergence brought heavy thundery showers to many areas. That day, 60.4 mm (2.38 in) fell at Nanyang Avenue, the highest daily total of the first half of October.

Readers can check the MSS website or myENV app for any heavy rain warning.

Heat and UV

The week will be hot, with highs above the October average. MSS forecasts a daily high of 34°C (93°F) from Monday to Thursday, against an October average daily maximum of 31.8°C (89.2°F). Its fortnightly outlook expects highs of 33°C to 35°C (91°F to 95°F) on most days, slightly above 35°C on a few days.

Nights will be warm. The four-day outlook gives lows of 25°C (77°F), while the fortnightly outlook says some nights may stay above 27°C (81°F). In the first half of October, most nights stayed above 27°C across several parts of the island.

UV levels are typically highest between 11am and 3pm. The NEA measures the UV index at Changi every 15 minutes from 7am to 7pm. The NEA notes that rain or cloud reduces the reading.

The Ministry of Health advice carried on the NEA page is to use sunscreen of at least SPF 30, seek shade or use an umbrella, and wear sunglasses that block UVA and UVB rays and a broad-brimmed hat.

Regional hazards

The region around Singapore is quiet for tropical cyclones and earthquakes, while several Indonesian volcanoes remain restless at a distance.

Tropical cyclones

No tropical cyclone or disturbance is in or near the South China Sea, and none has any bearing on Singapore. The Joint Typhoon Warning Center (JTWC) advisories list the systems below.

The western Pacific advisory was issued at 0600 UTC on October 18 (2pm SGT) and the Indian Ocean advisory at 0730 UTC (3.30pm SGT). Both report no tropical disturbance in the South China Sea or the Bay of Bengal.

Earthquakes

The USGS catalogue lists no earthquake of magnitude 4.5 or greater in the area from 9°S to 10°N and 93°E to 112°E since 0000 UTC on October 12. That area covers Sumatra, most of Java, the Malay Peninsula, western Borneo and the southern South China Sea. The catalogue was queried at 6.52am SGT on Monday, October 19. No tremors felt in Singapore were reported in the past week.

Volcanoes

Four volcanoes on Sumatra, Java and in the Sunda Strait erupted or remained active in the past week; none is reported to have disrupted flights at Changi. The Smithsonian and USGS Weekly Volcanic Activity Report covers October 8 to 14, 2026, and is five days old. Later eruptions come from reports of Indonesia’s Centre for Volcanology and Geological Hazard Mitigation (PVMBG).

The PVMBG-based reports on Krakatau, Marapi and Semeru mention no effect on aviation.

What to watch this week

The key moment is Tuesday night, October 20, when the NEA says a wind shift may bring Kalimantan smoke back to Singapore.

What could change the outlook

• Wind direction: the NEA links the change in air quality on Sunday to winds turning to blow from the south. Easterly or southeasterly winds carry Kalimantan smoke towards Singapore, so the forecast shift on Tuesday night is the main risk.
• Rain over the fire areas: the ASMC expects most of the southern ASEAN region to stay dry, apart from Peninsular Malaysia, northern and central Sumatra and parts of Borneo. Dry weather keeps the hotspot risk elevated.
• Showers over Singapore: thundery showers on Saturday, October 17 kept PM2.5 in the west below the Very High band, the NEA reported.
• Monsoon change: the ASMC and Ms Fu both point to inter-monsoon conditions from late October or early November, with the Northeast Monsoon from around early December expected to blow haze away from Singapore.

About this report

This report gathers the official forecasts and the latest hazard data for Singapore and the surrounding region into one weekly summary. It does not replace the warnings and advisories of MSS and the NEA.

Sources by topic

• Weather: MSS four-day outlook, 24-hour forecast, observations and fortnightly outlook; ASMC regional and seasonal outlooks.
• Haze: NEA daily haze situation updates; ASMC; regional readings and measures as reported by AsiaOne, The Straits Times and AFP (via Malay Mail, The Star, Kuwait Times and Manila Times); the Ministry of Sustainability and the Environment (MSE); IQAir.
• Heat and UV: MSS forecasts and the NEA UV index page.
• Tropical cyclones: JTWC significant tropical weather advisories.
• Earthquakes: USGS earthquake catalogue.
• Volcanoes: Smithsonian/USGS Weekly Volcanic Activity Report; PVMBG reports carried by Databoks and DotDotNews.

Glossary

Units

Temperatures are in degrees Celsius with Fahrenheit in brackets, rainfall in millimetres with inches in brackets and winds in km/h with mph in brackets. JTWC wind speeds are in knots and its distances in nautical miles, as issued. Earthquake distances and depths are in kilometres. Times are SGT (UTC+8) unless marked otherwise.

Limits

• Weather: the MSS four-day outlook used was updated at 4.55pm SGT on Sunday, October 18; MSS normally updates it at 5am and 6pm. It covers Monday to Thursday only. The fortnightly outlook covers October 16 to November 1.
• Haze: Monday morning’s readings had not been published when this report was prepared, so the latest are from 6pm SGT on Sunday, October 18, and are more than 12 hours old. The NEA gives 24-hour PSI as an island-wide range; only the highest (west) and lowest (north) regions were reported by region. ASMC regional text was last modified on October 16, and its hotspot counts are for October 17.
• IQAir: the ranking is hourly and changes through the day; it was read at about 7am SGT on October 19.
• Tropical cyclones: JTWC advisories were issued at 0600 UTC and 0730 UTC on October 18, about 15 to 17 hours before publication.
• Earthquakes: USGS locations and magnitudes are preliminary and may be revised.
• Volcanoes: the weekly report covers October 8 to 14 and is five days old. Later activity comes from news reports of PVMBG data.
• Tides: no tide table is included this week.

Frequently asked questions

Is the haze getting better or worse this week? It eased on Sunday, October 18, when winds turned to blow from the south and the PSI fell to 109–192 by 6pm. The NEA forecasts an Unhealthy 101–190 for Monday. It warns that winds may turn east-southeasterly from Tuesday night and bring Kalimantan smoke back.

What was the worst reading this past week? The 24-hour PSI reached 230, in the Very Unhealthy range, in the west at 10am on October 18. One-hour PM2.5 peaked at 288 µg/m³ in the west at 3pm on October 14, the highest of 2026 so far.

Should I exercise outdoors? On Monday the NEA advises healthy people to reduce prolonged or strenuous outdoor exertion. The elderly, pregnant women and children should minimise it, and people with chronic lung or heart disease should avoid it. Check the one-hour PM2.5 before going out.

What help is available for haze-related illness? The Haze Subsidy Scheme has run since October 12. Treatment for conditions such as asthma, bronchitis, conjunctivitis and upper respiratory tract infection is capped at S$10, or S$5 for seniors aged 67 and above. N95 masks are being distributed to vulnerable Singaporeans at community clubs and vending machines.

Will it rain this week? MSS forecasts afternoon thundery showers from Monday to Thursday, mainly short and localised. Rainfall for the second half of October is still expected to be below average over most of the island.

When will the haze season end? MSE and the ASMC expect inter-monsoon conditions from late October or early November. Ms Fu said the Northeast Monsoon from around early December should blow haze away from Singapore.

Is any typhoon heading for Singapore? No. The nearest active system, Super Typhoon Champi, was near Guam on October 18, far to the east. JTWC lists no system in or near the South China Sea.

Were there any earthquakes or volcanic ash affecting Singapore? No earthquake of magnitude 4.5 or greater was recorded in the region since October 12. Krakatau, Marapi, Merapi and Semeru remain active, but no effect on flights at Changi has been reported.