All areas · Central region

Southern Islands: what a changing climate means, and when

Southern Islands: little of the land is low-lying. Island-wide, flash-flood downpours reach 1.5 times their 1995–2014 level in about 64 years (2090) at today's pace.

At today's pace of emissions. An area-wide estimate for Southern Islands planning area, not a reading for any one building.

Open Southern Islands on the map

The three dates for Southern Islands

	Best case	At today's pace	Worst case
Coastal	Not before 2150	Not before 2150	Not before 2150
Heat	Not before 2100	Not before 2100	Not before 2100
Flash-flood downpours, island-wide	Not before 2100	209064 years · inside a 99-year lease	205630 years · inside a 30-year mortgage

Coastal: another tenth of the area's land sits below the safety line (3 m above mean sea level plus projected sea-level rise). Heat: 30 or more days a year at or above 35°C. Flash-flood downpours: days with 50 mm or more of rain across Singapore reach 1.5 times their 1995–2014 level; one date for every area, since the rain model can't tell neighbouring areas apart. For local flooding, see PUB's list below. Mortgage and lease are counted from today.

If you own in Southern Islands

The island-wide downpour date falls after a 30-year mortgage and inside a 99-year lease.

2026TodayAbout 15% of the land is below the safety line, protected by seawalls, tidal gates and drains.
205630-year mortgage endsIf taken out today.
2090Flash-flood downpours · 64 yearsIsland-wide, days with 50 mm or more of rain reach 1.5 times their 1995–2014 level.
2100HeatThis date is not reached by here, which is as far as that data goes.
212599-year lease endsIf it started today. Count from your own start date.
2150CoastalNo coastal date by here, which is as far as the sea-level data goes.

What to raise with your managing agent or town council

What is the ground level of our block, in metres above mean sea level?
How high is the basement carpark entrance above the road?
When is coastal protection planned for this stretch of coast?
Has our street or carpark ponded in heavy rain, and what was done about it?

If you are buying in Southern Islands

6 questions to take to a viewing.

Sea level: not before 2150

Little of the land is low-lying: 15% is below the safety line today and 19% by 2100.

What is the ground level of this block, in metres above mean sea level?
Is there a basement carpark or basement unit, and how high is its entrance above the road?
When is coastal protection planned for this stretch of coast, and has PUB's study for it been completed?

Flash floods: inside a 99-year lease

PUB lists no flood-prone area or hotspot in Southern Islands. Island-wide, days with 50 mm or more of rain go from 6.6 to 8.7 a year by 2100, reaching 1.5 times their 1995–2014 level by 2090.

Has this street flooded in heavy rain before?
Has the carpark or ground floor ponded in heavy rain before?

Heat: not before 2100

Days at or above 35°C go from 0 to 0 a year by 2100, staying under 30 a year.

Which way does the unit face, and how much afternoon sun does it take?

The numbers

	Today	2050	2100
Land below the safety line	15%	16%	19%
Days at or above 35°C a year	0	0	0
Days with 50 mm or more of rain a year, island-wide	6.6	7.6	8.7

At today's pace of emissions (SSP2-4.5). "Today" is modelled, not measured. Southern Islands covers 7.1 km² with a median ground height of 7.4 m.

NEA's Artillery Avenue (Sentosa) station recorded 3.4 days a year at or above 35°C in 2014 to 2024 (8 full years). The model gives 0.0 for the same years, as an average over the whole area.

How these are worked out

Ground heat in Southern Islands today

Tree cover	53% of land
Ground by day, vs island	−2.6°C 6 of 55, 1 = coolest
Ground at night, vs island	+0.4°C 22 of 55, 1 = coolest

Cooler than most of 55 areas by day; in the middle at night. Satellite readings of the ground surface, not the air: Landsat by day (2016–2025), MODIS at night, ESA WorldCover for trees. They describe today, not a forecast.

Other planning areas

An independent project, not produced or endorsed by CCRS, NEA, PUB, URA or any government agency. Low land in Singapore is protected today by seawalls, tidal gates and drains; these dates show when more of it will depend on that protection. Prompts, not property, insurance or investment advice.