Outside the usual range18 August 2026Environment
Meghalaya: average air quality index over the 7 days to 18 August 2026 was 66, above the 3-year median of 25 for the same week (+164%).
What happened
- 7-day mean to 18 August 2026
- 66
- That day alone: 41
- 3-year median, same week
- 25
- Change
- +41
- Change, per cent
- +164%
Why it matters
Daily figures mostly reflect the weather, so the observatory compares the mean of the last seven days with the same week in up to five earlier years. A breach means this week sits well outside what those years would lead you to expect, and by at least 15%. It is reported when an unusual run begins and for the latest day while it lasts, not every day.
For average air quality index, lower is better. This movement is therefore assessed as a deterioration.
Historical context
The number being averaged changed (about 2 now against 1 in earlier years), so part of this reflects which places are measured. Same week in earlier years: 2025 12, 2023 28, 2022 25. Daily values are compared as 7-day means because a single day mostly reflects weather.
The underlying data
| Period | Value | Release | Where in the document |
|---|---|---|---|
| 18 August 2026 | 41 | CPCB National Air Quality Index bulletin, 18 August 2026 (252 cities) | AQI bulletin p.3–11, Index Value column: mean of 2 city rows placed in Meghalaya — Byrnihat (Meghalaya) (p.3), Shillong (p.11) |
| 17 August 2026 | 32 | CPCB National Air Quality Index bulletin, 17 August 2026 (245 cities) | AQI bulletin p.3–11, Index Value column: mean of 2 city rows placed in Meghalaya — Byrnihat (Meghalaya) (p.3), Shillong (p.11) |
| 16 August 2026 | 81 | CPCB National Air Quality Index bulletin, 16 August 2026 (248 cities) | AQI bulletin p.3–11, Index Value column: mean of 2 city rows placed in Meghalaya — Byrnihat (Meghalaya) (p.3), Shillong (p.11) |
| 15 August 2026 | 78 | CPCB National Air Quality Index bulletin, 15 August 2026 (256 cities) | AQI bulletin p.3–12, Index Value column: mean of 2 city rows placed in Meghalaya — Byrnihat (Meghalaya) (p.3), Shillong (p.12) |
| 14 August 2026 | 53 | CPCB National Air Quality Index bulletin, 14 August 2026 (256 cities) | AQI bulletin p.3–11, Index Value column: mean of 2 city rows placed in Meghalaya — Byrnihat (Meghalaya) (p.3), Shillong (p.11) |
| 13 August 2026 |
Source and method
- Release
- CPCB National Air Quality Index bulletin, 18 August 2026 (252 cities)Archived fileOriginal URLFirst seen 3 Oct 2026
More signals for average air quality index in Meghalaya
- Meghalaya: average air quality index over the 7 days to 3 October 2026 was 128, above the 3-year median of 25 for the same week (+407%).
- Meghalaya: average air quality index over the 7 days to 15 September 2026 was 154, above the 4-year median of 20 for the same week (+655%).
- Meghalaya: average air quality index of 23 on 28 August 2026 is the lowest since 3 February 2026.
- Meghalaya: average air quality index over the 7 days to 7 August 2026 was 77, above the 4-year median of 20 for the same week (+288%).
Cite this
According to the India Health Observatory, Meghalaya: average air quality index over the 7 days to 18 August 2026 was 66, above the 3-year median of 25 for the same week (+164%). Source: Central Pollution Control Board, Ministry of Environment, Forest and Climate Change, CPCB National Air Quality Index bulletin, 18 August 2026 (252 cities). https://indiahealthobservatory.com/signals/air-quality-index--meghalaya--2026-08-18--baseline_breach
See also Meghalaya and 41 AQI in context.