19 – 25 Mar 2025 · Thailand · Wednesday to Tuesday, UTC+7

Thailand weekly air quality

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

127.5Weekly mean modelled AQI · Unhealthy for Sensitive Groups

Mean PM2.5: 46 µg/m³. Both means cover the selected cities hour by hour. They are not a national average or Thailand’s official index.

+45.6 AQI compared with the previous week’s mean of 81.9.

Highest hourly estimate: 265 in Bangkok · 23 Mar, 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, 19 Mar	97.6Moderate	53–182	37.4	192 / 192
Thu, 20 Mar	114.2Unhealthy for Sensitive Groups	57–188	38.7	192 / 192
Fri, 21 Mar	122.3Unhealthy for Sensitive Groups	59–206	46.6	192 / 192
Sat, 22 Mar	139.5Unhealthy for Sensitive Groups	76–228	53.9	192 / 192
Sun, 23 Mar	143.5Unhealthy for Sensitive Groups	60–265	52.8	192 / 192
Mon, 24 Mar	143.5Unhealthy for Sensitive Groups	60–239	51.8	192 / 192
Tue, 25 Mar	131.6Unhealthy for Sensitive Groups	64–204	40.9	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	91	85	83	84	84	85	86	87	88	90	92	93	95	97	98	99	106	112	116	118	118	116	113	108
Thu	107	106	107	107	108	108	109	109	109	109	108	108	108	107	107	110	117	127	133	135	133	130	124	117
Fri	113	111	112	111	110	110	111	111	112	113	114	114	115	117	119	123	131	140	146	146	145	141	138	132
Sat	130	130	131	132	132	133	133	133	134	134	134	133	132	132	134	141	151	157	160	160	156	150	146	141
Sun	138	137	136	135	136	136	137	137	136	135	135	135	135	136	138	143	151	161	166	164	159	156	154	152
Mon	150	147	146	143	141	139	138	136	135	135	134	135	137	141	143	147	151	159	160	157	151	146	140	135
Tue	132	129	129	128	127	127	126	125	124	123	122	122	121	120	121	129	144	154	158	155	147	139	132	127

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	163.8Unhealthy	265	57.4	168 / 168
Chiang Mai	158.3Unhealthy	207	67.3	168 / 168
Chiang Rai	153Unhealthy	175	66.1	168 / 168
Khon Kaen	137.7Unhealthy for Sensitive Groups	195	52	168 / 168
Nakhon Ratchasima	131.9Unhealthy for Sensitive Groups	204	49.5	168 / 168
Pattaya	126.6Unhealthy for Sensitive Groups	236	36.9	168 / 168
Phuket	79.9Moderate	143	21.3	168 / 168
Hat Yai	68.5Moderate	103	17.6	168 / 168

City-hours by category

Good: 0

Moderate: 401

Unhealthy for Sensitive Groups: 463

Unhealthy: 428

Very Unhealthy: 52

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	91	85	83	84	84	85	86	87	88	90	92	93	95	97	98	99	106	112	116	118	118	116	113	108
Thu	107	106	107	107	108	108	109	109	109	109	108	108	108	107	107	110	117	127	133	135	133	130	124	117
Fri	113	111	112	111	110	110	111	111	112	113	114	114	115	117	119	123	131	140	146	146	145	141	138	132
Sat	130	130	131	132	132	133	133	133	134	134	134	133	132	132	134	141	151	157	160	160	156	150	146	141
Sun	138	137	136	135	136	136	137	137	136	135	135	135	135	136	138	143	151	161	166	164	159	156	154	152
Mon	150	147	146	143	141	139	138	136	135	135	134	135	137	141	143	147	151	159	160	157	151	146	140	135
Tue	132	129	129	128	127	127	126	125	124	123	122	122	121	120	121	129	144	154	158	155	147	139	132	127

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	91	85	83	84	84	85	86	87	88	90	92	93	95	97	98	99	106	112	116	118	118	116	113	108
Thu	107	106	107	107	108	108	109	109	109	109	108	108	108	107	107	110	117	127	133	135	133	130	124	117
Fri	113	111	112	111	110	110	111	111	112	113	114	114	115	117	119	123	131	140	146	146	145	141	138	132
Sat	130	130	131	132	132	133	133	133	134	134	134	133	132	132	134	141	151	157	160	160	156	150	146	141
Sun	138	137	136	135	136	136	137	137	136	135	135	135	135	136	138	143	151	161	166	164	159	156	154	152
Mon	150	147	146	143	141	139	138	136	135	135	134	135	137	141	143	147	151	159	160	157	151	146	140	135
Tue	132	129	129	128	127	127	126	125	124	123	122	122	121	120	121	129	144	154	158	155	147	139	132	127

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	91	85	83	84	84	85	86	87	88	90	92	93	95	97	98	99	106	112	116	118	118	116	113	108
Thu	107	106	107	107	108	108	109	109	109	109	108	108	108	107	107	110	117	127	133	135	133	130	124	117
Fri	113	111	112	111	110	110	111	111	112	113	114	114	115	117	119	123	131	140	146	146	145	141	138	132
Sat	130	130	131	132	132	133	133	133	134	134	134	133	132	132	134	141	151	157	160	160	156	150	146	141
Sun	138	137	136	135	136	136	137	137	136	135	135	135	135	136	138	143	151	161	166	164	159	156	154	152
Mon	150	147	146	143	141	139	138	136	135	135	134	135	137	141	143	147	151	159	160	157	151	146	140	135
Tue	132	129	129	128	127	127	126	125	124	123	122	122	121	120	121	129	144	154	158	155	147	139	132	127