What is the current concentration of PM10 in Watertown, Massachusetts?

The current PM10 concentration at Watertown, Massachusetts is 126.353 μg/m3.

What is the current concentration of sulfur dioxide (SO2) in Watertown, Massachusetts?

The current sulfur dioxide (SO2) concentration at Watertown, Massachusetts is 0.384 ppb.

What is the current concentration of ozone (O3) in Watertown, Massachusetts?

The current ozone (O3) concentration at Watertown, Massachusetts is 25.785 ppm.

What is the current concentration of nitrogen dioxide (NO2) in Watertown, Massachusetts?

The current nitrogen dioxide (NO2) concentration at Watertown, Massachusetts is 4.769 ppb.

Watertown, Massachusetts live air quality index now

Name: Live air pollution levels in Watertown, Massachusetts today
Creator: Ambee

Stay updated with real-time air quality in Watertown, Massachusetts featuring accurate data on AQI, PM_2.5, PM₁₀, O₃, NO₂, SO₂, and CO levels. Use our interactive map and detailed forecasts to monitor pollution trends, manage health risks, and plan your daily activities with confidence.

Live AQI (Air Quality Index)

Moderate

Watertown, Massachusetts

Last updated: ... (Local time)

Major air pollutants in Watertown, Massachusetts

Good

Fine

Moderate

Poor

Very poor

Hazardous

Particulate Matter_2.5 (PM_2.5)

27.98 μg/m³

12.1

35.5

55.5

250.5

500.5+

Particulate Matter₁₀ (PM₁₀)

103.53 μg/m³

155

255

425

605+

Ozone (O₃)

24.34 ppb

201

201+

Sulfur Dioxide (SO₂)

0.29 ppb

186

605

1005+

Nitrogen Dioxide (NO₂)

5.88 ppb

101

361

1250

2050+

Carbon Monoxide (CO)

0.25 ppm

4.5

9.5

12.5

230.5

50.5+

Pollen Level

Low

Watertown, Massachusetts

Get Live Pollen Counts

Watertown, Massachusetts

Scroll To Air Quality Map

Track live Watertown, Massachusetts air quality forecast and history

Time	AQI	PM_2.5	PM₁₀	O₃	SO₂	NO₂	CO
2025-07-30T05:00:00.000Z	54 \| moderate	10.523 \| good	41.717 \| good	40.452 \| good	0.367 \| good	12.856 \| good	0.34 \| good
2025-07-30T06:00:00.000Z	49 \| good	8.734 \| good	37.786 \| good	36.137 \| good	0.284 \| good	21.404 \| good	0.281 \| good
2025-07-30T07:00:00.000Z	44 \| good	8.261 \| good	39.721 \| good	22.159 \| good	0.537 \| good	17.618 \| good	0.35 \| good
2025-07-30T08:00:00.000Z	56 \| moderate	12.01 \| good	46.099 \| good	19.887 \| good	0.543 \| good	18.048 \| good	0.347 \| good
2025-07-30T09:00:00.000Z	54 \| moderate	11.244 \| good	43.546 \| good	17.57 \| good	0.439 \| good	8.305 \| good	0.203 \| good
2025-07-30T10:00:00.000Z	52 \| moderate	10.468 \| good	40.894 \| good	21.076 \| good	0.424 \| good	9.394 \| good	0.209 \| good
2025-07-30T11:00:00.000Z	52 \| moderate	9.838 \| good	38.321 \| good	19.81 \| good	0.432 \| good	11.258 \| good	0.211 \| good
2025-07-30T12:00:00.000Z	52 \| moderate	9.58 \| good	37.668 \| good	17.23 \| good	0.437 \| good	11.629 \| good	0.313 \| good
2025-07-30T13:00:00.000Z	52 \| moderate	9.697 \| good	38.423 \| good	23.348 \| good	0.478 \| good	11.272 \| good	0.3 \| good
2025-07-30T14:00:00.000Z	52 \| moderate	10.138 \| good	40.713 \| good	27.239 \| good	0.609 \| good	10.478 \| good	0.258 \| good
2025-07-30T15:00:00.000Z	52 \| moderate	10.321 \| good	41.094 \| good	28.596 \| good	0.456 \| good	7.682 \| good	0.218 \| good
2025-07-30T16:00:00.000Z	54 \| moderate	10.581 \| good	42.309 \| good	35.804 \| good	0.476 \| good	8.277 \| good	0.209 \| good
2025-07-30T17:00:00.000Z	54 \| moderate	10.868 \| good	43.826 \| good	38.011 \| good	0.722 \| good	11.961 \| good	0.25 \| good
2025-07-30T18:00:00.000Z	54 \| moderate	11.195 \| good	46.508 \| good	37.815 \| good	0.62 \| good	9.967 \| good	0.247 \| good
2025-07-30T19:00:00.000Z	56 \| moderate	11.565 \| good	46.974 \| good	48.756 \| good	0.624 \| good	9.147 \| good	0.253 \| good
2025-07-30T20:00:00.000Z	56 \| moderate	11.696 \| good	46.974 \| good	48.514 \| good	0.577 \| good	8.66 \| good	0.253 \| good
2025-07-30T21:00:00.000Z	56 \| moderate	11.642 \| good	46.633 \| good	43.14 \| good	0.632 \| good	9.311 \| good	0.302 \| good
2025-07-30T22:00:00.000Z	54 \| moderate	11.498 \| good	46.514 \| good	40.532 \| good	0.536 \| good	9.222 \| good	0.341 \| good
2025-07-30T23:00:00.000Z	54 \| moderate	11.293 \| good	45.94 \| good	35.76 \| good	0.715 \| good	14.205 \| good	0.255 \| good
2025-07-31T00:00:00.000Z	54 \| moderate	10.722 \| good	43.32 \| good	40.885 \| good	0.484 \| good	7.304 \| good	0.255 \| good
2025-07-31T01:00:00.000Z	54 \| moderate	10.579 \| good	42.445 \| good	39.662 \| good	0.436 \| good	11.442 \| good	0.339 \| good
2025-07-31T02:00:00.000Z	52 \| moderate	10.5 \| good	42.11 \| good	36.263 \| good	0.438 \| good	10.441 \| good	0.294 \| good
2025-07-31T03:00:00.000Z	52 \| moderate	10.135 \| good	39.735 \| good	33.084 \| good	0.435 \| good	8.113 \| good	0.253 \| good
2025-07-31T04:00:00.000Z	52 \| moderate	10.135 \| good	39.735 \| good	33.381 \| good	0.432 \| good	8.122 \| good	0.253 \| good
2025-07-31T05:00:00.000Z	52 \| moderate	10.135 \| good	39.735 \| good	37.804 \| good	0.432 \| good	10.953 \| good	0.3 \| good
2025-07-31T06:00:00.000Z	53 \| moderate	10.41 \| good	58.773 \| fine	34.784 \| good	0.855 \| good	11.7 \| good	0.319 \| good
2025-07-31T07:00:00.000Z	71 \| moderate	20.334 \| fine	60.526 \| fine	20.835 \| good	0.385 \| good	11.701 \| good	0.198 \| good
2025-07-31T08:00:00.000Z	49 \| good	9.008 \| good	34.344 \| good	28.872 \| good	0.393 \| good	12.608 \| good	0.198 \| good
2025-07-31T09:00:00.000Z	49 \| good	8.766 \| good	33.753 \| good	28.356 \| good	0.457 \| good	6.354 \| good	0.159 \| good
2025-07-31T10:00:00.000Z	49 \| good	9.01 \| good	34.855 \| good	29.661 \| good	0.456 \| good	5.189 \| good	0.164 \| good
2025-07-31T11:00:00.000Z	52 \| moderate	9.59 \| good	36.894 \| good	24.704 \| good	0.407 \| good	5.236 \| good	0.255 \| good
2025-07-31T12:00:00.000Z	54 \| moderate	11.326 \| good	43.78 \| good	26.064 \| good	0.431 \| good	7.35 \| good	0.253 \| good
2025-07-31T13:00:00.000Z	60 \| moderate	14.211 \| fine	55.575 \| fine	24.282 \| good	0.453 \| good	8.943 \| good	0.303 \| good
2025-07-31T14:00:00.000Z	66 \| moderate	17.171 \| fine	66.303 \| fine	25.134 \| good	0.38 \| good	8.766 \| good	0.303 \| good
2025-07-31T15:00:00.000Z	71 \| moderate	19.729 \| fine	75.552 \| fine	25.805 \| good	0.38 \| good	8.764 \| good	0.353 \| good
2025-07-31T16:00:00.000Z	77 \| moderate	23.457 \| fine	89.017 \| fine	26.749 \| good	0.435 \| good	7.011 \| good	0.353 \| good
2025-07-31T17:00:00.000Z	86 \| moderate	27.567 \| fine	103.47 \| fine	21.608 \| good	0.38 \| good	7.311 \| good	0.303 \| good
2025-07-31T18:00:00.000Z	90 \| moderate	29.959 \| fine	111.923 \| fine	20.335 \| good	0.34 \| good	6.592 \| good	0.303 \| good
2025-07-31T19:00:00.000Z	97 \| moderate	34.374 \| fine	129.262 \| fine	24.343 \| good	0.38 \| good	5.902 \| good	0.355 \| good
2025-07-31T20:00:00.000Z	97 \| moderate	33.565 \| fine	126.353 \| fine	25.785 \| good	0.384 \| good	4.769 \| good	0.306 \| good
2025-07-31T21:00:00.000Z	94 \| moderate	32.205 \| fine	119.968 \| fine	25.605 \| good	0.327 \| good	5.755 \| good	0.3 \| good
2025-07-31T22:00:00.000Z	92 \| moderate	31.07 \| fine	114.911 \| fine	24.436 \| good	0.34 \| good	6.74 \| good	0.3 \| good
2025-07-31T23:00:00.000Z	60 \| moderate	13.85 \| fine	61.395 \| fine	20.726 \| good	0.828 \| good	6.555 \| good	0.29 \| good
2025-08-01T00:00:00.000Z	92 \| moderate	30.522 \| fine	113.695 \| fine	22.067 \| good	0.343 \| good	8.132 \| good	0.3 \| good
2025-08-01T01:00:00.000Z	88 \| moderate	29.106 \| fine	107.763 \| fine	18.445 \| good	0.342 \| good	6.469 \| good	0.303 \| good
2025-08-01T02:00:00.000Z	88 \| moderate	28.951 \| fine	106.399 \| fine	20.615 \| good	0.287 \| good	5.347 \| good	0.25 \| good
2025-08-01T03:00:00.000Z	86 \| moderate	27.981 \| fine	103.534 \| fine	24.344 \| good	0.287 \| good	5.876 \| good	0.25 \| good
2025-08-01T04:00:00.000Z	86 \| moderate	27.981 \| fine	103.534 \| fine	24.344 \| good	0.287 \| good	5.876 \| good	0.25 \| good
2025-07-31T22:00:00.000Z	56 \| moderate	11.779 \| good	52.444 \| good	18.559 \| good	1 \| good	6.471 \| good	0.273 \| good
2025-07-31T23:00:00.000Z	56 \| moderate	12.423 \| fine	56.366 \| fine	18.165 \| good	0.974 \| good	7.356 \| good	0.276 \| good
2025-08-01T00:00:00.000Z	58 \| moderate	12.524 \| fine	56.95 \| fine	20.728 \| good	0.949 \| good	8.242 \| good	0.279 \| good
2025-08-01T01:00:00.000Z	60 \| moderate	13.812 \| fine	61.568 \| fine	18.495 \| good	0.905 \| good	7.598 \| good	0.273 \| good
2025-08-01T02:00:00.000Z	64 \| moderate	16.494 \| fine	72.959 \| fine	17.938 \| good	0.86 \| good	6.954 \| good	0.266 \| good
2025-08-01T03:00:00.000Z	66 \| moderate	16.751 \| fine	74.688 \| fine	20.068 \| good	0.815 \| good	6.309 \| good	0.26 \| good
2025-08-01T04:00:00.000Z	66 \| moderate	17.393 \| fine	76.894 \| fine	22.353 \| good	0.802 \| good	5.726 \| good	0.253 \| good
2025-08-01T05:00:00.000Z	66 \| moderate	17.403 \| fine	77.022 \| fine	23.494 \| good	0.79 \| good	5.143 \| good	0.247 \| good
2025-08-01T06:00:00.000Z	64 \| moderate	16.254 \| fine	72.438 \| fine	23.166 \| good	0.777 \| good	4.559 \| good	0.24 \| good
2025-08-01T07:00:00.000Z	62 \| moderate	14.931 \| fine	66.44 \| fine	24.319 \| good	0.74 \| good	4.027 \| good	0.234 \| good
2025-08-01T08:00:00.000Z	58 \| moderate	13.256 \| fine	59.258 \| fine	24.029 \| good	0.704 \| good	3.494 \| good	0.227 \| good
2025-08-01T09:00:00.000Z	49 \| good	8.881 \| good	39.231 \| good	23.72 \| good	0.667 \| good	2.962 \| good	0.22 \| good
2025-08-01T10:00:00.000Z	49 \| good	9.324 \| good	41.634 \| good	21.472 \| good	0.658 \| good	3.683 \| good	0.22 \| good
2025-08-01T11:00:00.000Z	44 \| good	8.238 \| good	36.004 \| good	18.913 \| good	0.65 \| good	4.404 \| good	0.221 \| good
2025-08-01T12:00:00.000Z	44 \| good	8.324 \| good	36.793 \| good	16.742 \| good	0.641 \| good	5.125 \| good	0.221 \| good
2025-08-01T13:00:00.000Z	49 \| good	9.448 \| good	41.989 \| good	17.21 \| good	0.625 \| good	4.501 \| good	0.209 \| good
2025-08-01T14:00:00.000Z	49 \| good	9.131 \| good	40.799 \| good	18.257 \| good	0.608 \| good	3.877 \| good	0.197 \| good
2025-08-01T15:00:00.000Z	52 \| moderate	9.834 \| good	43.775 \| good	18.421 \| good	0.591 \| good	3.253 \| good	0.185 \| good
2025-08-01T16:00:00.000Z	49 \| good	9.478 \| good	42.394 \| good	22.28 \| good	0.578 \| good	2.792 \| good	0.182 \| good
2025-08-01T17:00:00.000Z	38 \| good	6.897 \| good	30.33 \| good	27.843 \| good	0.565 \| good	2.33 \| good	0.179 \| good
2025-08-01T18:00:00.000Z	33 \| good	5.841 \| good	25.316 \| good	28.533 \| good	0.552 \| good	1.868 \| good	0.177 \| good
2025-08-01T19:00:00.000Z	33 \| good	6.009 \| good	26.788 \| good	27.386 \| good	0.589 \| good	2.007 \| good	0.176 \| good
2025-08-01T20:00:00.000Z	33 \| good	6.306 \| good	27.975 \| good	28.056 \| good	0.625 \| good	2.146 \| good	0.176 \| good
2025-08-01T21:00:00.000Z	33 \| good	5.973 \| good	26.364 \| good	27.057 \| good	0.662 \| good	2.285 \| good	0.176 \| good
2025-08-01T22:00:00.000Z	38 \| good	6.64 \| good	29.593 \| good	25.566 \| good	0.771 \| good	4.518 \| good	0.189 \| good
2025-08-01T23:00:00.000Z	38 \| good	6.988 \| good	30.864 \| good	22.948 \| good	0.88 \| good	6.752 \| good	0.202 \| good
2025-08-02T00:00:00.000Z	49 \| good	8.574 \| good	37.552 \| good	21.886 \| good	0.989 \| good	8.985 \| good	0.215 \| good
2025-08-02T01:00:00.000Z	49 \| good	9.228 \| good	40.809 \| good	18.745 \| good	1.107 \| good	10.613 \| good	0.227 \| good
2025-08-02T02:00:00.000Z	52 \| moderate	9.567 \| good	42.784 \| good	18.78 \| good	1.226 \| good	12.241 \| good	0.239 \| good
2025-08-02T03:00:00.000Z	54 \| moderate	10.75 \| good	47.496 \| good	19.226 \| good	1.344 \| good	13.869 \| good	0.251 \| good
2025-08-02T04:00:00.000Z	54 \| moderate	10.726 \| good	47.689 \| good	20.778 \| good	1.322 \| good	12.217 \| good	0.24 \| good
2025-08-02T05:00:00.000Z	56 \| moderate	11.624 \| good	50.884 \| good	21.179 \| good	1.3 \| good	10.564 \| good	0.228 \| good
2025-08-02T06:00:00.000Z	54 \| moderate	10.778 \| good	47.786 \| good	19.544 \| good	1.278 \| good	8.912 \| good	0.216 \| good
2025-08-02T07:00:00.000Z	52 \| moderate	9.609 \| good	42.937 \| good	19.52 \| good	1.178 \| good	7.752 \| good	0.209 \| good
2025-08-02T08:00:00.000Z	49 \| good	8.72 \| good	38.118 \| good	17.491 \| good	1.079 \| good	6.592 \| good	0.202 \| good
2025-08-02T09:00:00.000Z	38 \| good	6.815 \| good	30.058 \| good	15.648 \| good	0.979 \| good	5.431 \| good	0.194 \| good
2025-08-02T10:00:00.000Z	44 \| good	7.708 \| good	34.036 \| good	15.352 \| good	0.95 \| good	5.356 \| good	0.2 \| good
2025-08-02T11:00:00.000Z	52 \| moderate	9.8 \| good	43.712 \| good	16.679 \| good	0.922 \| good	5.281 \| good	0.205 \| good
2025-08-02T12:00:00.000Z	54 \| moderate	10.5 \| good	46.646 \| good	21.583 \| good	0.893 \| good	5.206 \| good	0.21 \| good
2025-08-02T13:00:00.000Z	52 \| moderate	10.196 \| good	44.979 \| good	26.883 \| good	0.872 \| good	4.311 \| good	0.2 \| good
2025-08-02T14:00:00.000Z	44 \| good	8.33 \| good	36.788 \| good	32.916 \| good	0.851 \| good	3.416 \| good	0.19 \| good
2025-08-02T15:00:00.000Z	44 \| good	8.15 \| good	35.792 \| good	36.335 \| good	0.83 \| good	2.522 \| good	0.18 \| good
2025-08-02T16:00:00.000Z	44 \| good	7.855 \| good	34.591 \| good	36.502 \| good	0.795 \| good	2.323 \| good	0.178 \| good
2025-08-02T17:00:00.000Z	49 \| good	8.521 \| good	37.453 \| good	32.499 \| good	0.759 \| good	2.124 \| good	0.176 \| good
2025-08-02T18:00:00.000Z	44 \| good	8.244 \| good	36.453 \| good	35.499 \| good	0.724 \| good	1.925 \| good	0.174 \| good
2025-08-02T19:00:00.000Z	44 \| good	7.984 \| good	34.824 \| good	38.41 \| good	0.725 \| good	2.23 \| good	0.175 \| good
2025-08-02T20:00:00.000Z	44 \| good	8.169 \| good	35.703 \| good	38.874 \| good	0.726 \| good	2.535 \| good	0.176 \| good
2025-08-02T21:00:00.000Z	38 \| good	7.1 \| good	31.338 \| good	38.807 \| good	0.727 \| good	2.841 \| good	0.178 \| good

Watertown

Get reliable air quality data to drive your business

Watertown, Massachusetts air quality map: Track AQI near you

0.31ppm

How accurate is Massachusetts, USA air quality data?

Air quality data and pollutant measurements for Massachusetts, USA adhere to strict US EPA standards. The data is collected from multiple reliable sources, including satellites and ground-based monitoring stations. This data is further analyzed and enhanced using machine learning and advanced algorithms that factor in elements such as traffic and population density, ensuring accurate and reliable results.

Source: Ambee Data Sources

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Frequently asked questions

How often is the air quality data for Watertown, Massachusetts updated?

The air quality for Watertown, Massachusetts is updated every hour.

When was the worst air quality at Watertown, Massachusetts in the last 24 hrs?

The worst air quality in Watertown, Massachusetts in the last 24 hours was observed at 08:00:00 on 2025-07-31.

When was the best air quality at Watertown, Massachusetts in the last 24 hrs?

In the last 24 hrs, the best air quality in Watertown, Massachusetts was observed at 10:00:00 on 2025-07-31.

What is the current air quality in Watertown, Massachusetts?

The current air quality in Watertown, Massachusetts is 97, categorized as Moderate based on real-time data.

What pollutant is the most common in Watertown, Massachusetts?

The most common pollutant in Watertown, Massachusetts is PM2.5.

What should I do if the air quality in Watertown, Massachusetts is poor?

If the air quality in Watertown, Massachusetts is poor, consider staying indoors and wearing a mask to protect yourself.

What is the current concentration of PM_2.5 in Watertown, Massachusetts?

The current PM_2.5 concentration at Watertown, Massachusetts is 33.565 μg/m³.

What is the current concentration of PM₁₀ in Watertown, Massachusetts?

The current PM₁₀ concentration at Watertown, Massachusetts is 126.353 μg/m³.

What is the current concentration of carbon monoxide (CO) in Watertown, Massachusetts?

The current carbon monoxide (CO) concentration at Watertown, Massachusetts is 0.306 ppm.

What is the current concentration of sulfur dioxide (SO₂) in Watertown, Massachusetts?

The current sulfur dioxide (SO₂) concentration at Watertown, Massachusetts is 0.384 ppb.

What is the current concentration of ozone (O₃) in Watertown, Massachusetts?

The current ozone (O₃) concentration at Watertown, Massachusetts is 25.785 ppm.

What is the current concentration of nitrogen dioxide (NO₂) in Watertown, Massachusetts?

The current nitrogen dioxide (NO₂) concentration at Watertown, Massachusetts is 4.769 ppb.

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Time	AQI	PM_2.5	PM₁₀	O₃	SO₂	NO₂	CO
2025-07-30T05:00:00.000Z	54 \| moderate	10.523 \| good	41.717 \| good	40.452 \| good	0.367 \| good	12.856 \| good	0.34 \| good
2025-07-30T06:00:00.000Z	49 \| good	8.734 \| good	37.786 \| good	36.137 \| good	0.284 \| good	21.404 \| good	0.281 \| good
2025-07-30T07:00:00.000Z	44 \| good	8.261 \| good	39.721 \| good	22.159 \| good	0.537 \| good	17.618 \| good	0.35 \| good
2025-07-30T08:00:00.000Z	56 \| moderate	12.01 \| good	46.099 \| good	19.887 \| good	0.543 \| good	18.048 \| good	0.347 \| good
2025-07-30T09:00:00.000Z	54 \| moderate	11.244 \| good	43.546 \| good	17.57 \| good	0.439 \| good	8.305 \| good	0.203 \| good
2025-07-30T10:00:00.000Z	52 \| moderate	10.468 \| good	40.894 \| good	21.076 \| good	0.424 \| good	9.394 \| good	0.209 \| good
2025-07-30T11:00:00.000Z	52 \| moderate	9.838 \| good	38.321 \| good	19.81 \| good	0.432 \| good	11.258 \| good	0.211 \| good
2025-07-30T12:00:00.000Z	52 \| moderate	9.58 \| good	37.668 \| good	17.23 \| good	0.437 \| good	11.629 \| good	0.313 \| good
2025-07-30T13:00:00.000Z	52 \| moderate	9.697 \| good	38.423 \| good	23.348 \| good	0.478 \| good	11.272 \| good	0.3 \| good
2025-07-30T14:00:00.000Z	52 \| moderate	10.138 \| good	40.713 \| good	27.239 \| good	0.609 \| good	10.478 \| good	0.258 \| good
2025-07-30T15:00:00.000Z	52 \| moderate	10.321 \| good	41.094 \| good	28.596 \| good	0.456 \| good	7.682 \| good	0.218 \| good
2025-07-30T16:00:00.000Z	54 \| moderate	10.581 \| good	42.309 \| good	35.804 \| good	0.476 \| good	8.277 \| good	0.209 \| good
2025-07-30T17:00:00.000Z	54 \| moderate	10.868 \| good	43.826 \| good	38.011 \| good	0.722 \| good	11.961 \| good	0.25 \| good
2025-07-30T18:00:00.000Z	54 \| moderate	11.195 \| good	46.508 \| good	37.815 \| good	0.62 \| good	9.967 \| good	0.247 \| good
2025-07-30T19:00:00.000Z	56 \| moderate	11.565 \| good	46.974 \| good	48.756 \| good	0.624 \| good	9.147 \| good	0.253 \| good
2025-07-30T20:00:00.000Z	56 \| moderate	11.696 \| good	46.974 \| good	48.514 \| good	0.577 \| good	8.66 \| good	0.253 \| good
2025-07-30T21:00:00.000Z	56 \| moderate	11.642 \| good	46.633 \| good	43.14 \| good	0.632 \| good	9.311 \| good	0.302 \| good
2025-07-30T22:00:00.000Z	54 \| moderate	11.498 \| good	46.514 \| good	40.532 \| good	0.536 \| good	9.222 \| good	0.341 \| good
2025-07-30T23:00:00.000Z	54 \| moderate	11.293 \| good	45.94 \| good	35.76 \| good	0.715 \| good	14.205 \| good	0.255 \| good
2025-07-31T00:00:00.000Z	54 \| moderate	10.722 \| good	43.32 \| good	40.885 \| good	0.484 \| good	7.304 \| good	0.255 \| good
2025-07-31T01:00:00.000Z	54 \| moderate	10.579 \| good	42.445 \| good	39.662 \| good	0.436 \| good	11.442 \| good	0.339 \| good
2025-07-31T02:00:00.000Z	52 \| moderate	10.5 \| good	42.11 \| good	36.263 \| good	0.438 \| good	10.441 \| good	0.294 \| good
2025-07-31T03:00:00.000Z	52 \| moderate	10.135 \| good	39.735 \| good	33.084 \| good	0.435 \| good	8.113 \| good	0.253 \| good
2025-07-31T04:00:00.000Z	52 \| moderate	10.135 \| good	39.735 \| good	33.381 \| good	0.432 \| good	8.122 \| good	0.253 \| good
2025-07-31T05:00:00.000Z	52 \| moderate	10.135 \| good	39.735 \| good	37.804 \| good	0.432 \| good	10.953 \| good	0.3 \| good
2025-07-31T06:00:00.000Z	53 \| moderate	10.41 \| good	58.773 \| fine	34.784 \| good	0.855 \| good	11.7 \| good	0.319 \| good
2025-07-31T07:00:00.000Z	71 \| moderate	20.334 \| fine	60.526 \| fine	20.835 \| good	0.385 \| good	11.701 \| good	0.198 \| good
2025-07-31T08:00:00.000Z	49 \| good	9.008 \| good	34.344 \| good	28.872 \| good	0.393 \| good	12.608 \| good	0.198 \| good
2025-07-31T09:00:00.000Z	49 \| good	8.766 \| good	33.753 \| good	28.356 \| good	0.457 \| good	6.354 \| good	0.159 \| good
2025-07-31T10:00:00.000Z	49 \| good	9.01 \| good	34.855 \| good	29.661 \| good	0.456 \| good	5.189 \| good	0.164 \| good
2025-07-31T11:00:00.000Z	52 \| moderate	9.59 \| good	36.894 \| good	24.704 \| good	0.407 \| good	5.236 \| good	0.255 \| good
2025-07-31T12:00:00.000Z	54 \| moderate	11.326 \| good	43.78 \| good	26.064 \| good	0.431 \| good	7.35 \| good	0.253 \| good
2025-07-31T13:00:00.000Z	60 \| moderate	14.211 \| fine	55.575 \| fine	24.282 \| good	0.453 \| good	8.943 \| good	0.303 \| good
2025-07-31T14:00:00.000Z	66 \| moderate	17.171 \| fine	66.303 \| fine	25.134 \| good	0.38 \| good	8.766 \| good	0.303 \| good
2025-07-31T15:00:00.000Z	71 \| moderate	19.729 \| fine	75.552 \| fine	25.805 \| good	0.38 \| good	8.764 \| good	0.353 \| good
2025-07-31T16:00:00.000Z	77 \| moderate	23.457 \| fine	89.017 \| fine	26.749 \| good	0.435 \| good	7.011 \| good	0.353 \| good
2025-07-31T17:00:00.000Z	86 \| moderate	27.567 \| fine	103.47 \| fine	21.608 \| good	0.38 \| good	7.311 \| good	0.303 \| good
2025-07-31T18:00:00.000Z	90 \| moderate	29.959 \| fine	111.923 \| fine	20.335 \| good	0.34 \| good	6.592 \| good	0.303 \| good
2025-07-31T19:00:00.000Z	97 \| moderate	34.374 \| fine	129.262 \| fine	24.343 \| good	0.38 \| good	5.902 \| good	0.355 \| good
2025-07-31T20:00:00.000Z	97 \| moderate	33.565 \| fine	126.353 \| fine	25.785 \| good	0.384 \| good	4.769 \| good	0.306 \| good
2025-07-31T21:00:00.000Z	94 \| moderate	32.205 \| fine	119.968 \| fine	25.605 \| good	0.327 \| good	5.755 \| good	0.3 \| good
2025-07-31T22:00:00.000Z	92 \| moderate	31.07 \| fine	114.911 \| fine	24.436 \| good	0.34 \| good	6.74 \| good	0.3 \| good
2025-07-31T23:00:00.000Z	60 \| moderate	13.85 \| fine	61.395 \| fine	20.726 \| good	0.828 \| good	6.555 \| good	0.29 \| good
2025-08-01T00:00:00.000Z	92 \| moderate	30.522 \| fine	113.695 \| fine	22.067 \| good	0.343 \| good	8.132 \| good	0.3 \| good
2025-08-01T01:00:00.000Z	88 \| moderate	29.106 \| fine	107.763 \| fine	18.445 \| good	0.342 \| good	6.469 \| good	0.303 \| good
2025-08-01T02:00:00.000Z	88 \| moderate	28.951 \| fine	106.399 \| fine	20.615 \| good	0.287 \| good	5.347 \| good	0.25 \| good
2025-08-01T03:00:00.000Z	86 \| moderate	27.981 \| fine	103.534 \| fine	24.344 \| good	0.287 \| good	5.876 \| good	0.25 \| good
2025-08-01T04:00:00.000Z	86 \| moderate	27.981 \| fine	103.534 \| fine	24.344 \| good	0.287 \| good	5.876 \| good	0.25 \| good
2025-07-31T22:00:00.000Z	56 \| moderate	11.779 \| good	52.444 \| good	18.559 \| good	1 \| good	6.471 \| good	0.273 \| good
2025-07-31T23:00:00.000Z	56 \| moderate	12.423 \| fine	56.366 \| fine	18.165 \| good	0.974 \| good	7.356 \| good	0.276 \| good
2025-08-01T00:00:00.000Z	58 \| moderate	12.524 \| fine	56.95 \| fine	20.728 \| good	0.949 \| good	8.242 \| good	0.279 \| good
2025-08-01T01:00:00.000Z	60 \| moderate	13.812 \| fine	61.568 \| fine	18.495 \| good	0.905 \| good	7.598 \| good	0.273 \| good
2025-08-01T02:00:00.000Z	64 \| moderate	16.494 \| fine	72.959 \| fine	17.938 \| good	0.86 \| good	6.954 \| good	0.266 \| good
2025-08-01T03:00:00.000Z	66 \| moderate	16.751 \| fine	74.688 \| fine	20.068 \| good	0.815 \| good	6.309 \| good	0.26 \| good
2025-08-01T04:00:00.000Z	66 \| moderate	17.393 \| fine	76.894 \| fine	22.353 \| good	0.802 \| good	5.726 \| good	0.253 \| good
2025-08-01T05:00:00.000Z	66 \| moderate	17.403 \| fine	77.022 \| fine	23.494 \| good	0.79 \| good	5.143 \| good	0.247 \| good
2025-08-01T06:00:00.000Z	64 \| moderate	16.254 \| fine	72.438 \| fine	23.166 \| good	0.777 \| good	4.559 \| good	0.24 \| good
2025-08-01T07:00:00.000Z	62 \| moderate	14.931 \| fine	66.44 \| fine	24.319 \| good	0.74 \| good	4.027 \| good	0.234 \| good
2025-08-01T08:00:00.000Z	58 \| moderate	13.256 \| fine	59.258 \| fine	24.029 \| good	0.704 \| good	3.494 \| good	0.227 \| good
2025-08-01T09:00:00.000Z	49 \| good	8.881 \| good	39.231 \| good	23.72 \| good	0.667 \| good	2.962 \| good	0.22 \| good
2025-08-01T10:00:00.000Z	49 \| good	9.324 \| good	41.634 \| good	21.472 \| good	0.658 \| good	3.683 \| good	0.22 \| good
2025-08-01T11:00:00.000Z	44 \| good	8.238 \| good	36.004 \| good	18.913 \| good	0.65 \| good	4.404 \| good	0.221 \| good
2025-08-01T12:00:00.000Z	44 \| good	8.324 \| good	36.793 \| good	16.742 \| good	0.641 \| good	5.125 \| good	0.221 \| good
2025-08-01T13:00:00.000Z	49 \| good	9.448 \| good	41.989 \| good	17.21 \| good	0.625 \| good	4.501 \| good	0.209 \| good
2025-08-01T14:00:00.000Z	49 \| good	9.131 \| good	40.799 \| good	18.257 \| good	0.608 \| good	3.877 \| good	0.197 \| good
2025-08-01T15:00:00.000Z	52 \| moderate	9.834 \| good	43.775 \| good	18.421 \| good	0.591 \| good	3.253 \| good	0.185 \| good
2025-08-01T16:00:00.000Z	49 \| good	9.478 \| good	42.394 \| good	22.28 \| good	0.578 \| good	2.792 \| good	0.182 \| good
2025-08-01T17:00:00.000Z	38 \| good	6.897 \| good	30.33 \| good	27.843 \| good	0.565 \| good	2.33 \| good	0.179 \| good
2025-08-01T18:00:00.000Z	33 \| good	5.841 \| good	25.316 \| good	28.533 \| good	0.552 \| good	1.868 \| good	0.177 \| good
2025-08-01T19:00:00.000Z	33 \| good	6.009 \| good	26.788 \| good	27.386 \| good	0.589 \| good	2.007 \| good	0.176 \| good
2025-08-01T20:00:00.000Z	33 \| good	6.306 \| good	27.975 \| good	28.056 \| good	0.625 \| good	2.146 \| good	0.176 \| good
2025-08-01T21:00:00.000Z	33 \| good	5.973 \| good	26.364 \| good	27.057 \| good	0.662 \| good	2.285 \| good	0.176 \| good
2025-08-01T22:00:00.000Z	38 \| good	6.64 \| good	29.593 \| good	25.566 \| good	0.771 \| good	4.518 \| good	0.189 \| good
2025-08-01T23:00:00.000Z	38 \| good	6.988 \| good	30.864 \| good	22.948 \| good	0.88 \| good	6.752 \| good	0.202 \| good
2025-08-02T00:00:00.000Z	49 \| good	8.574 \| good	37.552 \| good	21.886 \| good	0.989 \| good	8.985 \| good	0.215 \| good
2025-08-02T01:00:00.000Z	49 \| good	9.228 \| good	40.809 \| good	18.745 \| good	1.107 \| good	10.613 \| good	0.227 \| good
2025-08-02T02:00:00.000Z	52 \| moderate	9.567 \| good	42.784 \| good	18.78 \| good	1.226 \| good	12.241 \| good	0.239 \| good
2025-08-02T03:00:00.000Z	54 \| moderate	10.75 \| good	47.496 \| good	19.226 \| good	1.344 \| good	13.869 \| good	0.251 \| good
2025-08-02T04:00:00.000Z	54 \| moderate	10.726 \| good	47.689 \| good	20.778 \| good	1.322 \| good	12.217 \| good	0.24 \| good
2025-08-02T05:00:00.000Z	56 \| moderate	11.624 \| good	50.884 \| good	21.179 \| good	1.3 \| good	10.564 \| good	0.228 \| good
2025-08-02T06:00:00.000Z	54 \| moderate	10.778 \| good	47.786 \| good	19.544 \| good	1.278 \| good	8.912 \| good	0.216 \| good
2025-08-02T07:00:00.000Z	52 \| moderate	9.609 \| good	42.937 \| good	19.52 \| good	1.178 \| good	7.752 \| good	0.209 \| good
2025-08-02T08:00:00.000Z	49 \| good	8.72 \| good	38.118 \| good	17.491 \| good	1.079 \| good	6.592 \| good	0.202 \| good
2025-08-02T09:00:00.000Z	38 \| good	6.815 \| good	30.058 \| good	15.648 \| good	0.979 \| good	5.431 \| good	0.194 \| good
2025-08-02T10:00:00.000Z	44 \| good	7.708 \| good	34.036 \| good	15.352 \| good	0.95 \| good	5.356 \| good	0.2 \| good
2025-08-02T11:00:00.000Z	52 \| moderate	9.8 \| good	43.712 \| good	16.679 \| good	0.922 \| good	5.281 \| good	0.205 \| good
2025-08-02T12:00:00.000Z	54 \| moderate	10.5 \| good	46.646 \| good	21.583 \| good	0.893 \| good	5.206 \| good	0.21 \| good
2025-08-02T13:00:00.000Z	52 \| moderate	10.196 \| good	44.979 \| good	26.883 \| good	0.872 \| good	4.311 \| good	0.2 \| good
2025-08-02T14:00:00.000Z	44 \| good	8.33 \| good	36.788 \| good	32.916 \| good	0.851 \| good	3.416 \| good	0.19 \| good
2025-08-02T15:00:00.000Z	44 \| good	8.15 \| good	35.792 \| good	36.335 \| good	0.83 \| good	2.522 \| good	0.18 \| good
2025-08-02T16:00:00.000Z	44 \| good	7.855 \| good	34.591 \| good	36.502 \| good	0.795 \| good	2.323 \| good	0.178 \| good
2025-08-02T17:00:00.000Z	49 \| good	8.521 \| good	37.453 \| good	32.499 \| good	0.759 \| good	2.124 \| good	0.176 \| good
2025-08-02T18:00:00.000Z	44 \| good	8.244 \| good	36.453 \| good	35.499 \| good	0.724 \| good	1.925 \| good	0.174 \| good
2025-08-02T19:00:00.000Z	44 \| good	7.984 \| good	34.824 \| good	38.41 \| good	0.725 \| good	2.23 \| good	0.175 \| good
2025-08-02T20:00:00.000Z	44 \| good	8.169 \| good	35.703 \| good	38.874 \| good	0.726 \| good	2.535 \| good	0.176 \| good
2025-08-02T21:00:00.000Z	38 \| good	7.1 \| good	31.338 \| good	38.807 \| good	0.727 \| good	2.841 \| good	0.178 \| good

Watertown, Massachusetts live air quality index now

Major air pollutants in Watertown, Massachusetts

Particulate Matter2.5 (PM2.5)

Particulate Matter10 (PM10)

Ozone (O3)

Sulfur Dioxide (SO2)

Nitrogen Dioxide (NO2)

Carbon Monoxide (CO)

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Air quality in nearby cities

Belmont, Massachusetts

Newton, Massachusetts

Waltham, Massachusetts

Arlington, Massachusetts

Cambridge, Massachusetts

Brookline, Massachusetts

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Particulate Matter_2.5 (PM_2.5)

Particulate Matter₁₀ (PM₁₀)

Ozone (O₃)

Sulfur Dioxide (SO₂)

Nitrogen Dioxide (NO₂)

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