Air Quality in Waltham, United States

Windy
7.0°C · 60.1% humidity
7.0°
Feels 1.0°
19
Good
Air quality is satisfactory. Enjoy outdoor activities.
1 station

Nearby Monitoring Stations

AQI Forecast Calibrated
20 9pm
20
18
20 12am
32
32
32 3am
32
32
32 6am
32
32
32 9am
32
45
45 12pm
70
45
45 3pm
45
32
32 6pm
32
32
Station readings
20
20
18
CAMS model adj -5
25
25
25
25
37
37
37
37
37
37
37
37
37
37
50
50
75
50
50
50
37
37
37
37
AD 728×90

PM2.5 Trend (24h)

23h · 2 stations
60.1%
Humidity
58.7 km/h
Wind SSW
1031.8 hPa
Pressure
2.2
UV Moderate
GoodModerateUSGUnhealthyVery UnhealthyHazardous

What is the weather forecast for Waltham?

Temperature & Precipitation

PM2.54.6 µg/m³ ✓ WHO
Good
PM1020.55 µg/m³
Good
UV INDEX2.2
Moderate
AD 300×250
Station readings (1 station within 25 km)
4.6
Median
4.6
Average
4.6
Low
4.6
High
PM2.5 µg/m³ · Model: 23.4 · Bias: +18.8

What is the 7-day forecast for Waltham?

04-10
19.2° 3.4°
04-11
22.8° 7.9°
04-12
17.3° 7.3°
04-13
13.1° 8.5°
1.75 mm
04-14
26.5° 13.6°
0.25 mm
04-15
25.3° 19.1°
0.19 mm
04-16
14.3° 7.6°
0.56 mm
Both models agree Avg diff: 4.2°C

Where are air quality stations near Waltham?

33
Magazine Beach Park
10.1 km PM2.5: 7.9 µg/m³ PM10: 9.2 µg/m³
19
Nubian Square - DEP Station
13.6 km PM2.5: 4.5 µg/m³
34
Boston Roxbury
13.6 km
35
Boston
14.6 km
38
Boston Von Hillern
15.8 km
39
Milton Blue Hill Observatory
20.9 km
38
Milton Blue Hill Observatory
20.9 km
37
Milton Blue Hill Observatory
20.9 km
36
Lynn Water Treatment Plant
24.3 km
35
Lynn Water Treatment Plant
24.3 km

What cities are near Waltham?

19 Watertown 19 Belmont 19 Brighton 19 Chestnut Hill 19 Allston 19 Wellesley 19 Needham 19 Brookline 19 Cambridge 19 Somerville

Data sources: AQI from ground-level monitoring stations via AQICN. Weather forecast from ECMWF (IFS & CAMS models). AQI calculated using US EPA standard. Updated 2026-04-10T00:42 UTC.