9 – 15 Sep 2026 · Thailand · Wednesday to Tuesday, UTC+7

Thailand weekly air quality

Modelled US AQI · 8 cities · CAMS via Open-Meteo

50.1Weekly mean modelled AQI · Moderate

Mean PM2.5: 10.1 µg/m³. Both means cover the selected cities hour by hour. They are not a national average or Thailand’s official index.

+6.2 AQI compared with the previous week’s mean of 43.9.

Highest hourly estimate: 204 in Bangkok · 13 Sept, 19:00 GMT+7.

1344 of 1344 city-hours have a modelled AQI. These are estimates for roughly 45 km model grid cells, not monitoring-station measurements. How this report is made

Daily modelled US AQI

Day	Mean AQI	Low–high	Mean PM2.5 (µg/m³)	City-hours
Wed, 9 Sep	35.5Good	17–53	6.7	192 / 192
Thu, 10 Sep	41.4Good	20–66	9.3	192 / 192
Fri, 11 Sep	52.9Moderate	24–172	8.3	192 / 192
Sat, 12 Sep	53.4Moderate	18–182	11.3	192 / 192
Sun, 13 Sep	59.8Moderate	18–204	10.1	192 / 192
Mon, 14 Sep	52.9Moderate	21–165	10.5	192 / 192
Tue, 15 Sep	54.8Moderate	23–105	14.1	192 / 192

Hourly means (UTC+7)

Each cell averages the selected cities’ modelled AQI for that hour.

Day	0	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23
Wed	35	34	33	33	33	33	33	33	34	34	34	34	35	35	35	36	38	40	40	39	39	38	38	37
Thu	37	37	38	38	38	38	38	38	39	40	40	41	41	42	42	43	44	45	46	45	46	46	46	46
Fri	46	46	46	46	47	47	47	47	47	46	46	45	45	46	46	52	66	77	81	78	69	59	50	44
Sat	42	42	42	41	41	41	41	41	42	43	44	45	46	48	52	59	70	81	85	82	74	66	60	54
Sun	51	51	50	50	51	51	51	51	51	51	51	51	51	55	59	68	76	82	84	83	79	72	64	55
Mon	49	47	47	46	46	46	46	45	45	46	46	46	47	47	48	49	57	66	71	72	69	66	63	59
Tue	54	51	51	51	51	52	52	52	52	53	54	54	55	55	56	56	57	60	61	60	59	58	57	57

Cities by modelled US AQI

Sorted by weekly mean. Each city is a single model grid cell near its centre.

City	Mean AQI	Peak AQI	Mean PM2.5 (µg/m³)	Hours
Bangkok	79.2Moderate	204	17.5	168 / 168
Chiang Mai	57.2Moderate	113	13	168 / 168
Khon Kaen	54.9Moderate	110	11.2	168 / 168
Pattaya	50.6Moderate	144	8.6	168 / 168
Chiang Rai	46.8Good	89	8.3	168 / 168
Nakhon Ratchasima	45.9Good	87	7.8	168 / 168
Hat Yai	36.1Good	105	9.3	168 / 168
Phuket	30.2Good	42	4.7	168 / 168

City-hours by category

Good: 766

Moderate: 525

Unhealthy for Sensitive Groups: 33

Unhealthy: 18

Very Unhealthy: 2

Hazardous: 0

US AQI scale
AQI	Category
0–50	Good
51–100	Moderate
101–150	Unhealthy for Sensitive Groups
151–200	Unhealthy
201–300	Very Unhealthy
301+	Hazardous

How this report is made

Open-Meteo provides hourly estimates from the Copernicus Atmosphere Monitoring Service (CAMS) global model at roughly 45 km resolution. We use the grid cell nearest each city’s centre. Nearby places may share a cell, and local pollution can differ.

The AQI is the provider’s modelled US AQI across pollutants, one value per city per hour. Weekly, daily and hourly means average those values across the selected cities. PM2.5 is a concentration in µg/m³. These figures use a different basis from the measured PM2.5-derived AQI in the Malaysia and Singapore reports.

Days and hours use UTC+7. The report includes past model hours only, never forecasts. The previous-week comparison appears only when at least 90% of that week’s city-hours are available.

For official local readings and advice, visit Pollution Control Department · Air4Thai. Air-quality data: Open-Meteo and CAMS, licensed under CC BY 4.0. Haze Monitor is independent of these providers and local authorities.

Day	0	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23
Wed	35	34	33	33	33	33	33	33	34	34	34	34	35	35	35	36	38	40	40	39	39	38	38	37
Thu	37	37	38	38	38	38	38	38	39	40	40	41	41	42	42	43	44	45	46	45	46	46	46	46
Fri	46	46	46	46	47	47	47	47	47	46	46	45	45	46	46	52	66	77	81	78	69	59	50	44
Sat	42	42	42	41	41	41	41	41	42	43	44	45	46	48	52	59	70	81	85	82	74	66	60	54
Sun	51	51	50	50	51	51	51	51	51	51	51	51	51	55	59	68	76	82	84	83	79	72	64	55
Mon	49	47	47	46	46	46	46	45	45	46	46	46	47	47	48	49	57	66	71	72	69	66	63	59
Tue	54	51	51	51	51	52	52	52	52	53	54	54	55	55	56	56	57	60	61	60	59	58	57	57

Day	0	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23
Wed	35	34	33	33	33	33	33	33	34	34	34	34	35	35	35	36	38	40	40	39	39	38	38	37
Thu	37	37	38	38	38	38	38	38	39	40	40	41	41	42	42	43	44	45	46	45	46	46	46	46
Fri	46	46	46	46	47	47	47	47	47	46	46	45	45	46	46	52	66	77	81	78	69	59	50	44
Sat	42	42	42	41	41	41	41	41	42	43	44	45	46	48	52	59	70	81	85	82	74	66	60	54
Sun	51	51	50	50	51	51	51	51	51	51	51	51	51	55	59	68	76	82	84	83	79	72	64	55
Mon	49	47	47	46	46	46	46	45	45	46	46	46	47	47	48	49	57	66	71	72	69	66	63	59
Tue	54	51	51	51	51	52	52	52	52	53	54	54	55	55	56	56	57	60	61	60	59	58	57	57

Day	0	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23
Wed	35	34	33	33	33	33	33	33	34	34	34	34	35	35	35	36	38	40	40	39	39	38	38	37
Thu	37	37	38	38	38	38	38	38	39	40	40	41	41	42	42	43	44	45	46	45	46	46	46	46
Fri	46	46	46	46	47	47	47	47	47	46	46	45	45	46	46	52	66	77	81	78	69	59	50	44
Sat	42	42	42	41	41	41	41	41	42	43	44	45	46	48	52	59	70	81	85	82	74	66	60	54
Sun	51	51	50	50	51	51	51	51	51	51	51	51	51	55	59	68	76	82	84	83	79	72	64	55
Mon	49	47	47	46	46	46	46	45	45	46	46	46	47	47	48	49	57	66	71	72	69	66	63	59
Tue	54	51	51	51	51	52	52	52	52	53	54	54	55	55	56	56	57	60	61	60	59	58	57	57