19 – 25 Apr 2023 · Thailand · Wednesday to Tuesday, UTC+7

Thailand weekly air quality

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

90.7Weekly mean modelled AQI · Moderate

Mean PM2.5: 26.6 µg/m³. Both means cover the selected cities hour by hour. They are not a national average or Thailand’s official index.

-31.3 AQI compared with the previous week’s mean of 122.

Highest hourly estimate: 251 in Bangkok · 22 Apr, 18:00 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, 19 Apr	97.8Moderate	65–187	32.2	192 / 192
Thu, 20 Apr	100Moderate	50–236	27.2	192 / 192
Fri, 21 Apr	93.8Moderate	48–238	28.5	192 / 192
Sat, 22 Apr	96.2Moderate	55–251	30.4	192 / 192
Sun, 23 Apr	83.1Moderate	52–134	20.4	192 / 192
Mon, 24 Apr	78Moderate	53–212	24.4	192 / 192
Tue, 25 Apr	86.3Moderate	54–240	23.4	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	94	93	93	93	93	93	93	94	94	94	94	95	95	95	95	97	100	103	109	110	107	104	105	105
Thu	105	105	105	104	103	101	97	94	94	93	93	93	93	96	97	99	103	105	105	106	105	105	103	99
Fri	93	93	93	92	90	88	85	85	85	86	86	86	87	90	93	98	103	106	107	107	105	102	98	92
Sat	88	88	88	88	87	87	87	87	87	88	88	89	90	93	99	105	110	114	116	115	112	107	102	96
Sun	92	92	92	92	91	91	90	90	89	88	86	85	83	82	80	79	78	77	76	74	73	73	72	72
Mon	72	71	71	71	71	71	71	71	71	72	72	72	72	76	78	79	84	88	90	91	92	91	90	87
Tue	83	80	81	81	81	81	81	81	82	82	82	82	82	84	86	91	93	98	100	98	96	93	90	84

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	138.9Unhealthy for Sensitive Groups	251	38.3	168 / 168
Chiang Rai	119.8Unhealthy for Sensitive Groups	155	41	168 / 168
Chiang Mai	98.5Moderate	112	34.1	168 / 168
Khon Kaen	94.2Moderate	165	30	168 / 168
Nakhon Ratchasima	84.9Moderate	167	23.3	168 / 168
Pattaya	70Moderate	92	18.9	168 / 168
Hat Yai	60.9Moderate	72	14.2	168 / 168
Phuket	58.7Moderate	72	13.2	168 / 168

City-hours by category

Good: 14

Moderate: 953

Unhealthy for Sensitive Groups: 310

Unhealthy: 37

Very Unhealthy: 30

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	94	93	93	93	93	93	93	94	94	94	94	95	95	95	95	97	100	103	109	110	107	104	105	105
Thu	105	105	105	104	103	101	97	94	94	93	93	93	93	96	97	99	103	105	105	106	105	105	103	99
Fri	93	93	93	92	90	88	85	85	85	86	86	86	87	90	93	98	103	106	107	107	105	102	98	92
Sat	88	88	88	88	87	87	87	87	87	88	88	89	90	93	99	105	110	114	116	115	112	107	102	96
Sun	92	92	92	92	91	91	90	90	89	88	86	85	83	82	80	79	78	77	76	74	73	73	72	72
Mon	72	71	71	71	71	71	71	71	71	72	72	72	72	76	78	79	84	88	90	91	92	91	90	87
Tue	83	80	81	81	81	81	81	81	82	82	82	82	82	84	86	91	93	98	100	98	96	93	90	84

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	94	93	93	93	93	93	93	94	94	94	94	95	95	95	95	97	100	103	109	110	107	104	105	105
Thu	105	105	105	104	103	101	97	94	94	93	93	93	93	96	97	99	103	105	105	106	105	105	103	99
Fri	93	93	93	92	90	88	85	85	85	86	86	86	87	90	93	98	103	106	107	107	105	102	98	92
Sat	88	88	88	88	87	87	87	87	87	88	88	89	90	93	99	105	110	114	116	115	112	107	102	96
Sun	92	92	92	92	91	91	90	90	89	88	86	85	83	82	80	79	78	77	76	74	73	73	72	72
Mon	72	71	71	71	71	71	71	71	71	72	72	72	72	76	78	79	84	88	90	91	92	91	90	87
Tue	83	80	81	81	81	81	81	81	82	82	82	82	82	84	86	91	93	98	100	98	96	93	90	84

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	94	93	93	93	93	93	93	94	94	94	94	95	95	95	95	97	100	103	109	110	107	104	105	105
Thu	105	105	105	104	103	101	97	94	94	93	93	93	93	96	97	99	103	105	105	106	105	105	103	99
Fri	93	93	93	92	90	88	85	85	85	86	86	86	87	90	93	98	103	106	107	107	105	102	98	92
Sat	88	88	88	88	87	87	87	87	87	88	88	89	90	93	99	105	110	114	116	115	112	107	102	96
Sun	92	92	92	92	91	91	90	90	89	88	86	85	83	82	80	79	78	77	76	74	73	73	72	72
Mon	72	71	71	71	71	71	71	71	71	72	72	72	72	76	78	79	84	88	90	91	92	91	90	87
Tue	83	80	81	81	81	81	81	81	82	82	82	82	82	84	86	91	93	98	100	98	96	93	90	84