# Singapore Haze Prediction Model: latest forecast

Issued Sat 17 Oct, 4:18pm SGT. Independent, experimental model; not an official NEA forecast. Source: https://singaporehaze.io/

- PSI now: 191 (NEA 24-hour PSI, highest of Singapore's five areas).
- Most likely next 6 days: gets worse (77%): Peaks 270–410 around Tue 20 Oct.; clears early (16%): PSI 100 or below by Mon 19 Oct.
- Back below 100 (first day at 100 or below): 32% chance by Fri 23 Oct; even odds by Tue 27 Oct.
- Haze over (7 days in a row at 100 or below): 7% chance it has started by Mon 26 Oct.
- End of the haze season (rain-season outlook, experimental): most likely around 3 Dec (80% between 10 Nov and 24 Dec).

| Day | Best guess PSI | Likely range | Above 100 | Above 200 | Above 300 |
|---|---|---|---|---|---|
| Sun 18 Oct | 240 | 189–269 | 96% | 70% | 8% |
| Mon 19 Oct | 271 | 174–317 | 86% | 69% | 34% |
| Tue 20 Oct | 273 | 129–329 | 80% | 65% | 38% |
| Wed 21 Oct | 274 | 131–339 | 83% | 65% | 40% |
| Thu 22 Oct | 218 | 132–285 | 85% | 54% | 20% |
| Fri 23 Oct | 200 | 110–275 | 84% | 50% | 18% |
| Sat 24 Oct | 195 | 124–277 | 87% | 47% | 18% |
| Sun 25 Oct | 155 | 113–235 | 87% | 34% | 12% |
| Mon 26 Oct | 142 | 98–187 | 73% | 23% | 6% |
| Tue 27 Oct | 135 | 100–201 | 75% | 25% | 8% |
| Wed 28 Oct | 140 | 102–198 | 76% | 22% | 5% |
| Thu 29 Oct | 144 | 110–213 | 84% | 27% | 6% |
| Fri 30 Oct | 147 | 111–208 | 81% | 28% | 6% |
| Sat 31 Oct | 138 | 102–195 | 76% | 23% | 5% |
| Sun 1 Nov | 135 | 94–179 | 70% | 18% | 4% |

## Questions

**When will the haze in Singapore end?** The model gives a 32% chance the 24-hour PSI is back to 100 or below by Fri 23 Oct. The haze season most likely ends around 3 Dec, when steady rain sets in over the fire areas (experimental estimate).

**Will the haze get worse this week?** Gets worse: 77% chance. Peaks 270–410 around Tue 20 Oct. Clears early: 16% chance. PSI 100 or below by Mon 19 Oct. Stays unhealthy: 4% chance. Above 100 through Fri 23 Oct. Middle path near 130.

**Is this NEA's official haze forecast?** No. This is an independent, experimental model. For official readings and health advice, follow NEA at haze.gov.sg.

**How does the Singapore Haze Prediction Model work?** It traces the air arriving in Singapore back through up to 56 weather forecasts (NOAA GEFS and ECMWF's AI model), adds smoke from fires seen by NASA satellites, and simulates 100,000 possible next 15 days, weighted to match NEA's latest readings. The odds rerun every hour; the full model runs every 6 hours.

**How accurate is it?** In replays of the 2014, 2015, 2019 and 2023 haze seasons, about 85% of NEA readings fell inside the forecast's 90% range. For 1 to 6 days ahead the best guess was about as good as assuming PSI stays as it is today; for 7 to 15 days ahead it was clearly better. Every live forecast is scored daily on the Track record page.