28 Jan – 3 Feb 2026 · Thailand · Wednesday to Tuesday, UTC+7

Thailand weekly air quality

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

78.4Weekly mean modelled AQI · Moderate

Mean PM2.5: 21 µg/m³. Both means cover the selected cities hour by hour. They are not a national average or Thailand’s official index.

+1.9 AQI compared with the previous week’s mean of 76.5.

Highest hourly estimate: 214 in Bangkok · 30 Jan, 20:00 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, 28 Jan	80.2Moderate	51–160	20.9	192 / 192
Thu, 29 Jan	77.2Moderate	51–180	22.9	192 / 192
Fri, 30 Jan	84.3Moderate	53–214	23.6	192 / 192
Sat, 31 Jan	85.8Moderate	54–211	23.7	192 / 192
Sun, 1 Feb	81.2Moderate	52–173	20.5	192 / 192
Mon, 2 Feb	73.1Moderate	53–135	19.2	192 / 192
Tue, 3 Feb	66.9Moderate	43–129	16.3	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	83	82	81	80	80	79	78	77	77	77	77	77	76	76	76	79	84	90	93	90	86	80	75	73
Thu	73	73	72	72	72	71	71	71	71	71	72	72	72	73	73	74	79	89	95	95	91	88	83	79
Fri	78	77	77	77	77	77	77	77	77	77	77	77	77	77	77	81	89	100	106	106	103	98	94	90
Sat	85	81	78	78	78	78	78	78	78	78	78	78	78	78	79	83	94	105	110	108	103	98	92	87
Sun	81	78	78	79	78	79	79	79	78	78	77	77	77	77	77	78	85	95	100	98	91	82	75	73
Mon	72	72	72	72	71	71	71	71	71	70	70	70	70	70	70	70	75	82	87	86	80	73	71	70
Tue	69	69	69	68	68	68	67	66	66	66	66	65	65	65	65	65	65	70	73	72	68	65	64	64

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	122.5Unhealthy for Sensitive Groups	214	36.9	168 / 168
Chiang Mai	101.1Unhealthy for Sensitive Groups	160	33.3	168 / 168
Chiang Rai	82Moderate	121	24.7	168 / 168
Pattaya	79.9Moderate	126	18.9	168 / 168
Nakhon Ratchasima	64.1Moderate	108	15.3	168 / 168
Khon Kaen	62.5Moderate	115	14.9	168 / 168
Phuket	58.8Moderate	91	12.2	168 / 168
Hat Yai	56.2Moderate	64	11.8	168 / 168

City-hours by category

Good: 30

Moderate: 1089

Unhealthy for Sensitive Groups: 196

Unhealthy: 20

Very Unhealthy: 9

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	83	82	81	80	80	79	78	77	77	77	77	77	76	76	76	79	84	90	93	90	86	80	75	73
Thu	73	73	72	72	72	71	71	71	71	71	72	72	72	73	73	74	79	89	95	95	91	88	83	79
Fri	78	77	77	77	77	77	77	77	77	77	77	77	77	77	77	81	89	100	106	106	103	98	94	90
Sat	85	81	78	78	78	78	78	78	78	78	78	78	78	78	79	83	94	105	110	108	103	98	92	87
Sun	81	78	78	79	78	79	79	79	78	78	77	77	77	77	77	78	85	95	100	98	91	82	75	73
Mon	72	72	72	72	71	71	71	71	71	70	70	70	70	70	70	70	75	82	87	86	80	73	71	70
Tue	69	69	69	68	68	68	67	66	66	66	66	65	65	65	65	65	65	70	73	72	68	65	64	64

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	83	82	81	80	80	79	78	77	77	77	77	77	76	76	76	79	84	90	93	90	86	80	75	73
Thu	73	73	72	72	72	71	71	71	71	71	72	72	72	73	73	74	79	89	95	95	91	88	83	79
Fri	78	77	77	77	77	77	77	77	77	77	77	77	77	77	77	81	89	100	106	106	103	98	94	90
Sat	85	81	78	78	78	78	78	78	78	78	78	78	78	78	79	83	94	105	110	108	103	98	92	87
Sun	81	78	78	79	78	79	79	79	78	78	77	77	77	77	77	78	85	95	100	98	91	82	75	73
Mon	72	72	72	72	71	71	71	71	71	70	70	70	70	70	70	70	75	82	87	86	80	73	71	70
Tue	69	69	69	68	68	68	67	66	66	66	66	65	65	65	65	65	65	70	73	72	68	65	64	64

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	83	82	81	80	80	79	78	77	77	77	77	77	76	76	76	79	84	90	93	90	86	80	75	73
Thu	73	73	72	72	72	71	71	71	71	71	72	72	72	73	73	74	79	89	95	95	91	88	83	79
Fri	78	77	77	77	77	77	77	77	77	77	77	77	77	77	77	81	89	100	106	106	103	98	94	90
Sat	85	81	78	78	78	78	78	78	78	78	78	78	78	78	79	83	94	105	110	108	103	98	92	87
Sun	81	78	78	79	78	79	79	79	78	78	77	77	77	77	77	78	85	95	100	98	91	82	75	73
Mon	72	72	72	72	71	71	71	71	71	70	70	70	70	70	70	70	75	82	87	86	80	73	71	70
Tue	69	69	69	68	68	68	67	66	66	66	66	65	65	65	65	65	65	70	73	72	68	65	64	64