Country Background
HistoryAQIPM₂.₅PM₁₀COSO₂NO₂O₃

Boulder, Colorado, United States Historical Air Quality Analysis

Dive into detailed Air Quality Insights with historical data, monthly patterns, and yearly trends at your fingertips!

Good
050
Moderate
100
Poor
150
Unhealthy
200
Severe
300
Hazardous
301+

August Air Quality Analysis

Boulder, Colorado, United States

2022
2023
2024
2025
2026
AQI
.
Days

AQI Trends: Highest and Lowest

Highest AQI recorded on
21st Aug 2023
85AQI
Lowest AQI recorded on
18th Aug 2024
14AQI

Same Day Analysis (1st August):
On this day, AQI across the 5 years varied significantly: 2026 ranks 3rd highest AQI at 31 of Good air quality, showing improvement over 2025 and 2024 on the same day.

Day & Night AQI Trend: 1st Aug - 2nd Aug 2026

Boulder, Colorado, United States

AQI
Day
Night
.

5 AM1st Aug 2026

8 PM

4 AM2nd Aug 2026

Day time
Avg. Highest Time
5AM1st Aug

35AQI

Avg. Lowest Time
8PM1st Aug

26AQI

Night time
Avg. Highest Time
3AM2nd Aug

29AQI

Avg. Lowest Time
11PM1st Aug

24AQI

In the last 24 hours,

Boulder's AQI reached its highest point of 35 at 5 AM during the Day, while the lowest point, 24, was recorded at 11 PM during the Night between 1st Aug and 2nd Aug 2026.

Day & Night AQI Trend : Jul - Aug 2026

Boulder, Colorado, United States

JulAug
04th - 05th05th - 06th06th - 07th07th - 08th08th - 09th09th - 10th10th - 11th11th - 12th12th - 13th13th - 14th14th - 15th15th - 16th16th - 17th17th - 18th18th - 19th19th - 20th20th - 21st21st - 22nd22nd - 23rd23rd - 24th24th - 25th25th - 26th26th - 27th27th - 28th28th - 29th29th - 30th30th - 31st31st - 01st01st - 02nd02nd
Day
Night
4th Jul 2026245 AMAQI
4th Jul 2026226 AMAQI
4th Jul 2026237 AMAQI
4th Jul 2026218 AMAQI
4th Jul 2026249 AMAQI
4th Jul 20262210 AMAQI
4th Jul 20262611 AMAQI
4th Jul 20262612 PMAQI
4th Jul 2026261 PMAQI
4th Jul 2026252 PMAQI
4th Jul 2026263 PMAQI
4th Jul 2026234 PMAQI
4th Jul 2026235 PMAQI
4th Jul 2026246 PMAQI
4th Jul 2026257 PMAQI
4th Jul 2026228 PMAQI
4th Jul 2026229 PMAQI
4th Jul 20262210 PMAQI
4th Jul 20262411 PMAQI
5th Jul 20262512 AMAQI
5th Jul 2026271 AMAQI
5th Jul 2026292 AMAQI
5th Jul 2026303 AMAQI
5th Jul 2026264 AMAQI

21°C13/32°C

5th Jul 2026235 AMAQI
5th Jul 2026216 AMAQI
5th Jul 2026207 AMAQI
5th Jul 2026228 AMAQI
5th Jul 2026249 AMAQI
5th Jul 20262710 AMAQI
5th Jul 20262811 AMAQI
5th Jul 20262912 PMAQI
5th Jul 2026311 PMAQI
5th Jul 2026302 PMAQI
5th Jul 2026253 PMAQI
5th Jul 2026224 PMAQI
5th Jul 2026215 PMAQI
5th Jul 2026216 PMAQI
5th Jul 2026207 PMAQI
5th Jul 2026218 PMAQI
5th Jul 2026229 PMAQI
5th Jul 20262410 PMAQI
5th Jul 20262411 PMAQI
6th Jul 20262512 AMAQI
6th Jul 2026241 AMAQI
6th Jul 2026242 AMAQI
6th Jul 2026223 AMAQI
6th Jul 2026244 AMAQI

24°C13/34°C

6th Jul 2026235 AMAQI
6th Jul 2026226 AMAQI
6th Jul 2026237 AMAQI
6th Jul 2026328 AMAQI
6th Jul 2026419 AMAQI
6th Jul 20264610 AMAQI
6th Jul 20264711 AMAQI
6th Jul 20264312 PMAQI
6th Jul 2026441 PMAQI
6th Jul 2026452 PMAQI
6th Jul 2026473 PMAQI
6th Jul 2026514 PMAQI
6th Jul 2026505 PMAQI
6th Jul 2026466 PMAQI
6th Jul 2026477 PMAQI
6th Jul 2026458 PMAQI
6th Jul 2026379 PMAQI
6th Jul 20263610 PMAQI
6th Jul 20263311 PMAQI
7th Jul 20263612 AMAQI
7th Jul 2026361 AMAQI
7th Jul 2026352 AMAQI
7th Jul 2026353 AMAQI
7th Jul 2026354 AMAQI

25°C15/35°C

7th Jul 2026355 AMAQI
7th Jul 2026336 AMAQI
7th Jul 2026327 AMAQI
7th Jul 2026358 AMAQI
7th Jul 2026409 AMAQI
7th Jul 20264610 AMAQI
7th Jul 20264811 AMAQI
7th Jul 20265012 PMAQI
7th Jul 2026481 PMAQI
7th Jul 2026482 PMAQI
7th Jul 2026553 PMAQI
7th Jul 2026574 PMAQI
7th Jul 2026585 PMAQI
7th Jul 2026486 PMAQI
7th Jul 2026417 PMAQI
7th Jul 2026338 PMAQI
7th Jul 2026309 PMAQI
7th Jul 20262810 PMAQI
7th Jul 20262311 PMAQI
8th Jul 20261812 AMAQI
8th Jul 2026191 AMAQI
8th Jul 2026242 AMAQI
8th Jul 2026223 AMAQI
8th Jul 2026214 AMAQI

23°C14/33°C

8th Jul 2026195 AMAQI
8th Jul 2026186 AMAQI
8th Jul 2026187 AMAQI
8th Jul 2026188 AMAQI
8th Jul 2026249 AMAQI
8th Jul 20262910 AMAQI
8th Jul 20263111 AMAQI
8th Jul 20262612 PMAQI
8th Jul 2026441 PMAQI
8th Jul 2026302 PMAQI
8th Jul 2026243 PMAQI
8th Jul 2026184 PMAQI
8th Jul 2026335 PMAQI
8th Jul 2026246 PMAQI
8th Jul 2026197 PMAQI
8th Jul 2026198 PMAQI
8th Jul 2026179 PMAQI
8th Jul 20261510 PMAQI
8th Jul 20261411 PMAQI
9th Jul 20261212 AMAQI
9th Jul 2026111 AMAQI
9th Jul 2026102 AMAQI
9th Jul 2026113 AMAQI
9th Jul 2026114 AMAQI

23°C14/34°C

9th Jul 202695 AMAQI
9th Jul 2026146 AMAQI
9th Jul 2026167 AMAQI
9th Jul 202698 AMAQI
9th Jul 2026119 AMAQI
9th Jul 20261110 AMAQI
9th Jul 20261111 AMAQI
9th Jul 20261512 PMAQI
9th Jul 2026171 PMAQI
9th Jul 2026192 PMAQI
9th Jul 2026183 PMAQI
9th Jul 2026214 PMAQI
9th Jul 2026185 PMAQI
9th Jul 2026156 PMAQI
9th Jul 2026137 PMAQI
9th Jul 202698 PMAQI
9th Jul 2026139 PMAQI
9th Jul 20261510 PMAQI
9th Jul 20261011 PMAQI
10th Jul 20261112 AMAQI
10th Jul 202691 AMAQI
10th Jul 2026142 AMAQI
10th Jul 2026133 AMAQI
10th Jul 2026164 AMAQI

21°C14/33°C

10th Jul 2026195 AMAQI
10th Jul 2026206 AMAQI
10th Jul 2026207 AMAQI
10th Jul 2026228 AMAQI
10th Jul 2026129 AMAQI
10th Jul 20261210 AMAQI
10th Jul 20261211 AMAQI
10th Jul 20261412 PMAQI
10th Jul 2026131 PMAQI
10th Jul 2026142 PMAQI
10th Jul 2026163 PMAQI
10th Jul 2026194 PMAQI
10th Jul 2026175 PMAQI
10th Jul 2026246 PMAQI
10th Jul 2026177 PMAQI
10th Jul 2026118 PMAQI
10th Jul 2026109 PMAQI
10th Jul 20261010 PMAQI
10th Jul 20261211 PMAQI
11th Jul 20261012 AMAQI
11th Jul 2026111 AMAQI
11th Jul 2026102 AMAQI
11th Jul 2026103 AMAQI
11th Jul 202694 AMAQI

21°C11/32°C

11th Jul 2026115 AMAQI
11th Jul 2026116 AMAQI
11th Jul 2026157 AMAQI
11th Jul 2026148 AMAQI
11th Jul 2026109 AMAQI
11th Jul 20261110 AMAQI
11th Jul 20261111 AMAQI
11th Jul 20261212 PMAQI
11th Jul 2026131 PMAQI
11th Jul 2026132 PMAQI
11th Jul 2026143 PMAQI
11th Jul 2026174 PMAQI
11th Jul 2026175 PMAQI
11th Jul 2026146 PMAQI
11th Jul 2026157 PMAQI
11th Jul 2026148 PMAQI
11th Jul 2026139 PMAQI
11th Jul 20261410 PMAQI
11th Jul 20261211 PMAQI
12th Jul 20261412 AMAQI
12th Jul 2026131 AMAQI
12th Jul 2026132 AMAQI
12th Jul 2026123 AMAQI
12th Jul 2026124 AMAQI

24°C14/35°C

12th Jul 2026125 AMAQI
12th Jul 2026126 AMAQI
12th Jul 2026107 AMAQI
12th Jul 2026108 AMAQI
12th Jul 2026129 AMAQI
12th Jul 20261310 AMAQI
12th Jul 20261311 AMAQI
12th Jul 20261312 PMAQI
12th Jul 2026151 PMAQI
12th Jul 2026172 PMAQI
12th Jul 2026163 PMAQI
12th Jul 2026154 PMAQI
12th Jul 2026145 PMAQI
12th Jul 2026136 PMAQI
12th Jul 2026137 PMAQI
12th Jul 2026148 PMAQI
12th Jul 2026159 PMAQI
12th Jul 20261410 PMAQI
12th Jul 20261511 PMAQI
13th Jul 20261512 AMAQI
13th Jul 2026131 AMAQI
13th Jul 2026142 AMAQI
13th Jul 2026123 AMAQI
13th Jul 2026124 AMAQI

26°C16/36°C

13th Jul 2026135 AMAQI
13th Jul 2026116 AMAQI
13th Jul 2026127 AMAQI
13th Jul 2026168 AMAQI
13th Jul 2026189 AMAQI
13th Jul 20262110 AMAQI
13th Jul 20262311 AMAQI
13th Jul 20262712 PMAQI
13th Jul 2026251 PMAQI
13th Jul 2026232 PMAQI
13th Jul 2026253 PMAQI
13th Jul 2026274 PMAQI
13th Jul 2026295 PMAQI
13th Jul 2026296 PMAQI
13th Jul 2026267 PMAQI
13th Jul 2026268 PMAQI
13th Jul 2026249 PMAQI
13th Jul 20262410 PMAQI
13th Jul 20262111 PMAQI
14th Jul 20262112 AMAQI
14th Jul 2026211 AMAQI
14th Jul 2026192 AMAQI
14th Jul 2026183 AMAQI
14th Jul 2026174 AMAQI

26°C15/36°C

14th Jul 2026165 AMAQI
14th Jul 2026166 AMAQI
14th Jul 2026167 AMAQI
14th Jul 2026218 AMAQI
14th Jul 2026209 AMAQI
14th Jul 20262110 AMAQI
14th Jul 20262511 AMAQI
14th Jul 20262612 PMAQI
14th Jul 2026261 PMAQI
14th Jul 2026292 PMAQI
14th Jul 2026323 PMAQI
14th Jul 2026324 PMAQI
14th Jul 2026345 PMAQI
14th Jul 2026276 PMAQI
14th Jul 2026257 PMAQI
14th Jul 2026238 PMAQI
14th Jul 2026219 PMAQI
14th Jul 20262010 PMAQI
14th Jul 20261811 PMAQI
15th Jul 20261712 AMAQI
15th Jul 2026191 AMAQI
15th Jul 2026182 AMAQI
15th Jul 2026163 AMAQI
15th Jul 2026164 AMAQI

25°C15/34°C

15th Jul 2026155 AMAQI
15th Jul 2026146 AMAQI
15th Jul 2026147 AMAQI
15th Jul 2026188 AMAQI
15th Jul 2026209 AMAQI
15th Jul 20262210 AMAQI
15th Jul 20262411 AMAQI
15th Jul 20262512 PMAQI
15th Jul 2026271 PMAQI
15th Jul 2026292 PMAQI
15th Jul 2026303 PMAQI
15th Jul 2026304 PMAQI
15th Jul 2026305 PMAQI
15th Jul 2026276 PMAQI
15th Jul 2026267 PMAQI
15th Jul 2026268 PMAQI
15th Jul 2026249 PMAQI
15th Jul 20262510 PMAQI
15th Jul 20262311 PMAQI
16th Jul 20262412 AMAQI
16th Jul 2026241 AMAQI
16th Jul 2026202 AMAQI
16th Jul 2026193 AMAQI
16th Jul 2026174 AMAQI

24°C14/33°C

16th Jul 2026165 AMAQI
16th Jul 2026176 AMAQI
16th Jul 2026177 AMAQI
16th Jul 2026208 AMAQI
16th Jul 2026219 AMAQI
16th Jul 20262710 AMAQI
16th Jul 20262811 AMAQI
16th Jul 20263012 PMAQI
16th Jul 2026301 PMAQI
16th Jul 2026282 PMAQI
16th Jul 2026323 PMAQI
16th Jul 2026334 PMAQI
16th Jul 2026345 PMAQI
16th Jul 2026316 PMAQI
16th Jul 2026277 PMAQI
16th Jul 2026278 PMAQI
16th Jul 2026279 PMAQI
16th Jul 20262210 PMAQI
16th Jul 20261411 PMAQI
17th Jul 20261212 AMAQI
17th Jul 2026151 AMAQI
17th Jul 2026202 AMAQI
17th Jul 2026243 AMAQI
17th Jul 2026204 AMAQI

23°C15/33°C

17th Jul 2026255 AMAQI
17th Jul 2026296 AMAQI
17th Jul 2026307 AMAQI
17th Jul 2026298 AMAQI
17th Jul 2026269 AMAQI
17th Jul 20263010 AMAQI
17th Jul 20262511 AMAQI
17th Jul 20263212 PMAQI
17th Jul 2026321 PMAQI
17th Jul 2026332 PMAQI
17th Jul 2026323 PMAQI
17th Jul 2026334 PMAQI
17th Jul 2026335 PMAQI
17th Jul 2026266 PMAQI
17th Jul 2026207 PMAQI
17th Jul 2026318 PMAQI
17th Jul 2026339 PMAQI
17th Jul 20263410 PMAQI
17th Jul 20263311 PMAQI
18th Jul 20263312 AMAQI
18th Jul 2026281 AMAQI
18th Jul 2026302 AMAQI
18th Jul 2026303 AMAQI
18th Jul 2026304 AMAQI

24°C15/32°C

18th Jul 2026305 AMAQI
18th Jul 2026306 AMAQI
18th Jul 2026297 AMAQI
18th Jul 2026308 AMAQI
18th Jul 2026309 AMAQI
18th Jul 20263010 AMAQI
18th Jul 20263511 AMAQI
18th Jul 20263512 PMAQI
18th Jul 2026301 PMAQI
18th Jul 2026422 PMAQI
18th Jul 2026433 PMAQI
18th Jul 2026424 PMAQI
18th Jul 2026415 PMAQI
18th Jul 2026416 PMAQI
18th Jul 2026397 PMAQI
18th Jul 2026358 PMAQI
18th Jul 2026359 PMAQI
18th Jul 20263710 PMAQI
18th Jul 20262511 PMAQI
19th Jul 20263012 AMAQI
19th Jul 2026321 AMAQI
19th Jul 2026302 AMAQI
19th Jul 2026303 AMAQI
19th Jul 2026354 AMAQI

25°C15/33°C

19th Jul 2026335 AMAQI
19th Jul 2026326 AMAQI
19th Jul 2026267 AMAQI
19th Jul 2026328 AMAQI
19th Jul 2026259 AMAQI
19th Jul 20262810 AMAQI
19th Jul 20263711 AMAQI
19th Jul 20263112 PMAQI
19th Jul 2026291 PMAQI
19th Jul 2026252 PMAQI
19th Jul 2026293 PMAQI
19th Jul 2026244 PMAQI
19th Jul 2026295 PMAQI
19th Jul 2026246 PMAQI
19th Jul 2026207 PMAQI
19th Jul 2026308 PMAQI
19th Jul 2026309 PMAQI
19th Jul 20262510 PMAQI
19th Jul 20262511 PMAQI
20th Jul 20262912 AMAQI
20th Jul 2026291 AMAQI
20th Jul 2026272 AMAQI
20th Jul 2026293 AMAQI
20th Jul 2026304 AMAQI

25°C15/35°C

20th Jul 2026285 AMAQI
20th Jul 2026256 AMAQI
20th Jul 2026287 AMAQI
20th Jul 2026268 AMAQI
20th Jul 2026329 AMAQI
20th Jul 20262610 AMAQI
20th Jul 20262911 AMAQI
20th Jul 20263912 PMAQI
20th Jul 2026451 PMAQI
20th Jul 2026462 PMAQI
20th Jul 2026433 PMAQI
20th Jul 2026434 PMAQI
20th Jul 2026355 PMAQI
20th Jul 2026336 PMAQI
20th Jul 2026397 PMAQI
20th Jul 2026448 PMAQI
20th Jul 20264110 PMAQI
20th Jul 20264311 PMAQI
21st Jul 20264612 AMAQI
21st Jul 2026431 AMAQI
21st Jul 2026392 AMAQI
21st Jul 2026413 AMAQI
21st Jul 2026334 AMAQI

26°C18/37°C

21st Jul 2026285 AMAQI
21st Jul 2026316 AMAQI
21st Jul 2026327 AMAQI
21st Jul 2026408 AMAQI
21st Jul 2026439 AMAQI
21st Jul 20264610 AMAQI
21st Jul 20264711 AMAQI
21st Jul 20264612 PMAQI
21st Jul 2026401 PMAQI
21st Jul 2026402 PMAQI
21st Jul 2026353 PMAQI
21st Jul 2026384 PMAQI
21st Jul 2026345 PMAQI
21st Jul 2026316 PMAQI
21st Jul 2026307 PMAQI
21st Jul 2026278 PMAQI
21st Jul 2026319 PMAQI
21st Jul 20262910 PMAQI
21st Jul 20262511 PMAQI
22nd Jul 20263312 AMAQI
22nd Jul 2026331 AMAQI
22nd Jul 2026252 AMAQI
22nd Jul 2026323 AMAQI
22nd Jul 2026294 AMAQI

26°C19/35°C

22nd Jul 2026305 AMAQI
22nd Jul 2026306 AMAQI
22nd Jul 2026307 AMAQI
22nd Jul 2026328 AMAQI
22nd Jul 2026339 AMAQI
22nd Jul 20263510 AMAQI
22nd Jul 20262711 AMAQI
22nd Jul 20262712 PMAQI
22nd Jul 2026261 PMAQI
22nd Jul 2026262 PMAQI
22nd Jul 2026263 PMAQI
22nd Jul 2026244 PMAQI
22nd Jul 2026255 PMAQI
22nd Jul 2026246 PMAQI
22nd Jul 2026257 PMAQI
22nd Jul 2026258 PMAQI
22nd Jul 2026269 PMAQI
22nd Jul 20263210 PMAQI
22nd Jul 20263911 PMAQI
23rd Jul 20263212 AMAQI
23rd Jul 2026351 AMAQI
23rd Jul 2026292 AMAQI
23rd Jul 2026313 AMAQI
23rd Jul 2026374 AMAQI

22°C16/32°C

23rd Jul 2026335 AMAQI
23rd Jul 2026356 AMAQI
23rd Jul 2026297 AMAQI
23rd Jul 2026328 AMAQI
23rd Jul 2026329 AMAQI
23rd Jul 20263310 AMAQI
23rd Jul 20263311 AMAQI
23rd Jul 20263612 PMAQI
23rd Jul 2026371 PMAQI
23rd Jul 2026322 PMAQI
23rd Jul 2026283 PMAQI
23rd Jul 2026274 PMAQI
23rd Jul 2026265 PMAQI
23rd Jul 2026186 PMAQI
23rd Jul 2026207 PMAQI
23rd Jul 2026258 PMAQI
23rd Jul 2026339 PMAQI
23rd Jul 20263210 PMAQI
23rd Jul 20263911 PMAQI
24th Jul 20263712 AMAQI
24th Jul 2026251 AMAQI
24th Jul 2026332 AMAQI
24th Jul 2026333 AMAQI
24th Jul 2026324 AMAQI

22°C16/29°C

24th Jul 2026335 AMAQI
24th Jul 2026326 AMAQI
24th Jul 2026337 AMAQI
24th Jul 2026308 AMAQI
24th Jul 2026309 AMAQI
24th Jul 20263310 AMAQI
24th Jul 20262911 AMAQI
24th Jul 20263212 PMAQI
24th Jul 2026321 PMAQI
24th Jul 2026292 PMAQI
24th Jul 2026343 PMAQI
24th Jul 2026324 PMAQI
24th Jul 2026335 PMAQI
24th Jul 2026276 PMAQI
24th Jul 2026307 PMAQI
24th Jul 2026398 PMAQI
24th Jul 2026309 PMAQI
24th Jul 20263210 PMAQI
24th Jul 20263211 PMAQI
25th Jul 20262812 AMAQI
25th Jul 2026311 AMAQI
25th Jul 2026332 AMAQI
25th Jul 2026353 AMAQI
25th Jul 2026304 AMAQI

25°C16/34°C

25th Jul 2026305 AMAQI
25th Jul 2026306 AMAQI
25th Jul 2026287 AMAQI
25th Jul 2026308 AMAQI
25th Jul 2026309 AMAQI
25th Jul 20263010 AMAQI
25th Jul 20264611 AMAQI
25th Jul 20263712 PMAQI
25th Jul 2026281 PMAQI
25th Jul 2026252 PMAQI
25th Jul 2026163 PMAQI
25th Jul 2026254 PMAQI
25th Jul 2026275 PMAQI
25th Jul 2026276 PMAQI
25th Jul 2026257 PMAQI
25th Jul 2026298 PMAQI
25th Jul 2026259 PMAQI
25th Jul 20262510 PMAQI
25th Jul 20262511 PMAQI
26th Jul 20262812 AMAQI
26th Jul 2026121 AMAQI
26th Jul 2026182 AMAQI
26th Jul 2026253 AMAQI
26th Jul 2026294 AMAQI

26°C18/36°C

26th Jul 2026245 AMAQI
26th Jul 2026306 AMAQI
26th Jul 2026307 AMAQI
26th Jul 2026308 AMAQI
26th Jul 2026299 AMAQI
26th Jul 20263010 AMAQI
26th Jul 20263011 AMAQI
26th Jul 20263212 PMAQI
26th Jul 2026301 PMAQI
26th Jul 2026252 PMAQI
26th Jul 2026223 PMAQI
26th Jul 2026124 PMAQI
26th Jul 2026305 PMAQI
26th Jul 2026196 PMAQI
26th Jul 2026287 PMAQI
26th Jul 2026308 PMAQI
26th Jul 2026309 PMAQI
26th Jul 20263010 PMAQI
26th Jul 20262911 PMAQI
27th Jul 20263012 AMAQI
27th Jul 2026301 AMAQI
27th Jul 2026282 AMAQI
27th Jul 2026123 AMAQI
27th Jul 2026154 AMAQI

27°C21/36°C

27th Jul 2026145 AMAQI
27th Jul 2026186 AMAQI
27th Jul 2026257 AMAQI
27th Jul 2026328 AMAQI
27th Jul 2026259 AMAQI
27th Jul 20262910 AMAQI
27th Jul 20262811 AMAQI
27th Jul 20263412 PMAQI
27th Jul 2026251 PMAQI
27th Jul 2026302 PMAQI
27th Jul 2026293 PMAQI
27th Jul 2026264 PMAQI
27th Jul 2026275 PMAQI
27th Jul 2026366 PMAQI
27th Jul 2026177 PMAQI
27th Jul 2026308 PMAQI
27th Jul 2026299 PMAQI
27th Jul 20262910 PMAQI
27th Jul 20262411 PMAQI
28th Jul 20263512 AMAQI
28th Jul 2026421 AMAQI
28th Jul 2026362 AMAQI
28th Jul 2026303 AMAQI
28th Jul 2026394 AMAQI

24°C19/32°C

28th Jul 2026285 AMAQI
28th Jul 2026356 AMAQI
28th Jul 2026317 AMAQI
28th Jul 2026438 AMAQI
28th Jul 2026259 AMAQI
28th Jul 20264310 AMAQI
28th Jul 20263211 AMAQI
28th Jul 20263512 PMAQI
28th Jul 2026451 PMAQI
28th Jul 2026432 PMAQI
28th Jul 2026313 PMAQI
28th Jul 2026314 PMAQI
28th Jul 2026325 PMAQI
28th Jul 2026396 PMAQI
28th Jul 2026257 PMAQI
28th Jul 2026308 PMAQI
28th Jul 2026299 PMAQI
28th Jul 20262910 PMAQI
28th Jul 20262911 PMAQI
29th Jul 20263012 AMAQI
29th Jul 2026321 AMAQI
29th Jul 2026322 AMAQI
29th Jul 2026393 AMAQI
29th Jul 2026414 AMAQI

22°C16/32°C

29th Jul 2026475 AMAQI
29th Jul 2026566 AMAQI
29th Jul 2026317 AMAQI
29th Jul 2026418 AMAQI
29th Jul 2026449 AMAQI
29th Jul 20264310 AMAQI
29th Jul 20262911 AMAQI
29th Jul 20262412 PMAQI
29th Jul 2026321 PMAQI
29th Jul 2026322 PMAQI
29th Jul 2026273 PMAQI
29th Jul 2026324 PMAQI
29th Jul 2026185 PMAQI
29th Jul 2026306 PMAQI
29th Jul 2026377 PMAQI
29th Jul 2026298 PMAQI
29th Jul 2026239 PMAQI
29th Jul 20263410 PMAQI
29th Jul 20265211 PMAQI
30th Jul 20264412 AMAQI
30th Jul 2026301 AMAQI
30th Jul 2026442 AMAQI
30th Jul 2026393 AMAQI
30th Jul 2026274 AMAQI

21°C16/31°C

30th Jul 2026255 AMAQI
30th Jul 2026216 AMAQI
30th Jul 2026257 AMAQI
30th Jul 2026278 AMAQI
30th Jul 2026279 AMAQI
30th Jul 20264610 AMAQI
30th Jul 20262411 AMAQI
30th Jul 20262412 PMAQI
30th Jul 2026251 PMAQI
30th Jul 2026262 PMAQI
30th Jul 2026263 PMAQI
30th Jul 2026304 PMAQI
30th Jul 2026295 PMAQI
30th Jul 2026296 PMAQI
30th Jul 2026307 PMAQI
30th Jul 2026308 PMAQI
30th Jul 2026309 PMAQI
30th Jul 20263010 PMAQI
30th Jul 20262911 PMAQI
31st Jul 20263012 AMAQI
31st Jul 2026251 AMAQI
31st Jul 2026262 AMAQI
31st Jul 2026243 AMAQI
31st Jul 2026284 AMAQI

24°C16/33°C

31st Jul 2026285 AMAQI
31st Jul 2026276 AMAQI
31st Jul 2026287 AMAQI
31st Jul 2026308 AMAQI
31st Jul 2026349 AMAQI
31st Jul 20262810 AMAQI
31st Jul 20262811 AMAQI
31st Jul 20262812 PMAQI
31st Jul 2026281 PMAQI
31st Jul 2026302 PMAQI
31st Jul 2026283 PMAQI
31st Jul 2026284 PMAQI
31st Jul 2026305 PMAQI
31st Jul 2026306 PMAQI
31st Jul 2026307 PMAQI
31st Jul 2026308 PMAQI
31st Jul 2026319 PMAQI
31st Jul 20263110 PMAQI
31st Jul 20263111 PMAQI
1st Aug 20263112 AMAQI
1st Aug 2026311 AMAQI
1st Aug 2026312 AMAQI
1st Aug 2026303 AMAQI
1st Aug 2026344 AMAQI

21°C15/32°C

1st Aug 2026355 AMAQI
1st Aug 2026336 AMAQI
1st Aug 2026317 AMAQI
1st Aug 2026318 AMAQI
1st Aug 2026319 AMAQI
1st Aug 20263410 AMAQI
1st Aug 20263311 AMAQI
1st Aug 20263512 PMAQI
1st Aug 2026351 PMAQI
1st Aug 2026352 PMAQI
1st Aug 2026353 PMAQI
1st Aug 2026304 PMAQI
1st Aug 2026265 PMAQI
1st Aug 2026306 PMAQI
1st Aug 2026267 PMAQI
1st Aug 2026268 PMAQI
1st Aug 2026289 PMAQI
1st Aug 20262610 PMAQI
1st Aug 20262411 PMAQI
2nd Aug 20262612 AMAQI
2nd Aug 2026251 AMAQI
2nd Aug 2026262 AMAQI
2nd Aug 2026293 AMAQI
2nd Aug 2026294 AMAQI

23°C14/33°C

2nd Aug 2026285 AMAQI
5 AM
2nd Aug 2026286 AMAQI
2nd Aug 2026297 AMAQI
2nd Aug 2026278 AMAQI
2nd Aug 2026269 AMAQI
2nd Aug 20262810 AMAQI
2nd Aug 20262811 AMAQI
2nd Aug 20263012 PMAQI
12 PM
2nd Aug 2026281 PMAQI
2nd Aug 2026282 PMAQI
2nd Aug 2026283 PMAQI
2nd Aug 2026254 PMAQI
2nd Aug 2026365 PMAQI
2nd Aug 2026296 PMAQI
2nd Aug 2026457 PMAQI
2nd Aug 2026438 PMAQI
8 PM
2nd Aug 2026319 PMAQI
2nd Aug 20263010 PMAQI
2nd Aug 20262611 PMAQI
12 AM
4 AM

27°C17/38°C

Day time
Avg. Highest Time
12 PM - 2 PM

30AQI

3 hours / Day
90 hours / Month
Avg. Lowest Time
5 AM

24AQI

1 hours / Day
30 hours / Month
In the last 30 days, during the daytime, the highest AQI was between 12 PM to 2 PM (Avg. 30), while the lowest AQI was between 5 AM to 5 AM (Avg. 24).
Night time
Avg. Highest Time
10 PM

27AQI

1 hours / Day
30 hours / Month
Avg. Lowest Time
1 AM - 4 AM

25AQI

4 hours / Day
120 hours / Month
In the last 30 days, during the daytime, the highest AQI was between 10 PM to 10 PM (Avg. 27), while the lowest AQI was between 1 AM to 4 AM (Avg. 25).

2026 Days Vs Air Quality

Boulder, Colorado, United States

2026

100%

210

Total number of days with different AQI categories in last 214 days in 2026 (151 days remaining)

Good
210 Days
Moderate
0 Days
Poor
0 Days
Unhealthy
0 Days
Severe
0 Days
Hazardous
0 Days

Under WHO’s Safe Air Quality Limits: 100%

Health Risk Level:

Very Low

In 2026, 100% of 214 days were within WHO’s safe air quality limits. The risk of health issues is Very Low, but health impacts are still unclear.

Annual Air Quality Insights

Boulder, Colorado, United States

AQI levels in 2026

AQI (US)
PM₂.₅
PM₁₀
CO
SO₂
NO₂
O₃
Sun.Mon.Tue.Wed.Thu.Fri.Sat.

Jan.

Feb.

Mar.

Apr.

May

Jun.

Jul.

Aug.

Sep.

Oct.

Nov.

Dec.

-1th undefined 2026
-1th undefined 2026
-1th undefined 2026
-1th undefined 2026
1st January 2026
23AQI (US)
2nd January 2026
26AQI (US)
3rd January 2026
29AQI (US)
4th January 2026
21AQI (US)
5th January 2026
24AQI (US)
6th January 2026
17AQI (US)
7th January 2026
18AQI (US)
8th January 2026
18AQI (US)
9th January 2026
18AQI (US)
10th January 2026
16AQI (US)
11th January 2026
17AQI (US)
12th January 2026
31AQI (US)
13th January 2026
23AQI (US)
14th January 2026
13AQI (US)
15th January 2026
22AQI (US)
16th January 2026
23AQI (US)
17th January 2026
12AQI (US)
18th January 2026
15AQI (US)
19th January 2026
21AQI (US)
20th January 2026
39AQI (US)
21st January 2026
20AQI (US)
22nd January 2026
25AQI (US)
23rd January 2026
22AQI (US)
24th January 2026
30AQI (US)
25th January 2026
21AQI (US)
26th January 2026
28AQI (US)
27th January 2026
22AQI (US)
28th January 2026
29AQI (US)
29th January 2026
31AQI (US)
30th January 2026
33AQI (US)
31st January 2026
24AQI (US)
1st February 2026
21AQI (US)
2nd February 2026
24AQI (US)
3rd February 2026
21AQI (US)
4th February 2026
28AQI (US)
5th February 2026
22AQI (US)
6th February 2026
21AQI (US)
7th February 2026
21AQI (US)
8th February 2026
27AQI (US)
9th February 2026
26AQI (US)
10th February 2026
23AQI (US)
11th February 2026
24AQI (US)
12th February 2026
25AQI (US)
13th February 2026
21AQI (US)
14th February 2026
27AQI (US)
15th February 2026
21AQI (US)
16th February 2026
22AQI (US)
17th February 2026
29AQI (US)
18th February 2026
19AQI (US)
19th February 2026
24AQI (US)
20th February 2026
18AQI (US)
21st February 2026
17AQI (US)
22nd February 2026
18AQI (US)
23rd February 2026
23AQI (US)
24th February 2026
30AQI (US)
25th February 2026
27AQI (US)
26th February 2026
18AQI (US)
27th February 2026
20AQI (US)
28th February 2026
18AQI (US)
1st March 2026
22AQI (US)
2nd March 2026
30AQI (US)
3rd March 2026
16AQI (US)
4th March 2026
19AQI (US)
5th March 2026
19AQI (US)
6th March 2026
29AQI (US)
7th March 2026
26AQI (US)
8th March 2026
27AQI (US)
9th March 2026
23AQI (US)
10th March 2026
21AQI (US)
11th March 2026
19AQI (US)
12th March 2026
28AQI (US)
13th March 2026
20AQI (US)
14th March 2026
30AQI (US)
15th March 2026
19AQI (US)
16th March 2026
22AQI (US)
17th March 2026
20AQI (US)
18th March 2026
22AQI (US)
19th March 2026
17AQI (US)
20th March 2026
22AQI (US)
21st March 2026
17AQI (US)
22nd March 2026
24AQI (US)
23rd March 2026
22AQI (US)
24th March 2026
22AQI (US)
25th March 2026
19AQI (US)
26th March 2026
36AQI (US)
27th March 2026
25AQI (US)
28th March 2026
21AQI (US)
29th March 2026
20AQI (US)
30th March 2026
23AQI (US)
31st March 2026
29AQI (US)
1st April 2026
28AQI (US)
2nd April 2026
19AQI (US)
3rd April 2026
26AQI (US)
4th April 2026
17AQI (US)
5th April 2026
20AQI (US)
6th April 2026
22AQI (US)
7th April 2026
29AQI (US)
8th April 2026
29AQI (US)
9th April 2026
25AQI (US)
10th April 2026
29AQI (US)
11th April 2026
20AQI (US)
12th April 2026
16AQI (US)
13th April 2026
17AQI (US)
14th April 2026
18AQI (US)
15th April 2026
23AQI (US)
16th April 2026
21AQI (US)
17th April 2026
18th April 2026
20AQI (US)
19th April 2026
17AQI (US)
20th April 2026
21AQI (US)
21st April 2026
20AQI (US)
22nd April 2026
23rd April 2026
34AQI (US)
24th April 2026
21AQI (US)
25th April 2026
18AQI (US)
26th April 2026
17AQI (US)
27th April 2026
15AQI (US)
28th April 2026
19AQI (US)
29th April 2026
15AQI (US)
30th April 2026
17AQI (US)
1st May 2026
15AQI (US)
2nd May 2026
13AQI (US)
3rd May 2026
13AQI (US)
4th May 2026
21AQI (US)
5th May 2026
26AQI (US)
6th May 2026
22AQI (US)
7th May 2026
14AQI (US)
8th May 2026
18AQI (US)
9th May 2026
10th May 2026
25AQI (US)
11th May 2026
16AQI (US)
12th May 2026
26AQI (US)
13th May 2026
33AQI (US)
14th May 2026
30AQI (US)
15th May 2026
27AQI (US)
16th May 2026
22AQI (US)
17th May 2026
18AQI (US)
18th May 2026
33AQI (US)
19th May 2026
28AQI (US)
20th May 2026
18AQI (US)
21st May 2026
20AQI (US)
22nd May 2026
20AQI (US)
23rd May 2026
23AQI (US)
24th May 2026
18AQI (US)
25th May 2026
18AQI (US)
26th May 2026
17AQI (US)
27th May 2026
14AQI (US)
28th May 2026
18AQI (US)
29th May 2026
16AQI (US)
30th May 2026
13AQI (US)
31st May 2026
15AQI (US)
1st June 2026
16AQI (US)
2nd June 2026
16AQI (US)
3rd June 2026
19AQI (US)
4th June 2026
18AQI (US)
5th June 2026
25AQI (US)
6th June 2026
21AQI (US)
7th June 2026
22AQI (US)
8th June 2026
25AQI (US)
9th June 2026
21AQI (US)
10th June 2026
33AQI (US)
11th June 2026
27AQI (US)
12th June 2026
24AQI (US)
13th June 2026
23AQI (US)
14th June 2026
21AQI (US)
15th June 2026
21AQI (US)
16th June 2026
22AQI (US)
17th June 2026
30AQI (US)
18th June 2026
29AQI (US)
19th June 2026
35AQI (US)
20th June 2026
37AQI (US)
21st June 2026
24AQI (US)
22nd June 2026
23AQI (US)
23rd June 2026
35AQI (US)
24th June 2026
22AQI (US)
25th June 2026
16AQI (US)
26th June 2026
13AQI (US)
27th June 2026
15AQI (US)
28th June 2026
44AQI (US)
29th June 2026
27AQI (US)
30th June 2026
31AQI (US)
1st July 2026
40AQI (US)
2nd July 2026
35AQI (US)
3rd July 2026
36AQI (US)
4th July 2026
24AQI (US)
5th July 2026
25AQI (US)
6th July 2026
37AQI (US)
7th July 2026
40AQI (US)
8th July 2026
23AQI (US)
9th July 2026
13AQI (US)
10th July 2026
15AQI (US)
11th July 2026
12AQI (US)
12th July 2026
13AQI (US)
13th July 2026
20AQI (US)
14th July 2026
23AQI (US)
15th July 2026
22AQI (US)
16th July 2026
24AQI (US)
17th July 2026
27AQI (US)
18th July 2026
34AQI (US)
19th July 2026
29AQI (US)
20th July 2026
34AQI (US)
21st July 2026
37AQI (US)
22nd July 2026
29AQI (US)
23rd July 2026
31AQI (US)
24th July 2026
31AQI (US)
25th July 2026
29AQI (US)
26th July 2026
27AQI (US)
27th July 2026
26AQI (US)
28th July 2026
34AQI (US)
29th July 2026
35AQI (US)
30th July 2026
30AQI (US)
31st July 2026
29AQI (US)
1st August 2026
31AQI (US)
2nd August 2026
3rd August 2026
4th August 2026
5th August 2026
6th August 2026
7th August 2026
8th August 2026
9th August 2026
10th August 2026
11th August 2026
12th August 2026
13th August 2026
14th August 2026
15th August 2026
16th August 2026
17th August 2026
18th August 2026
19th August 2026
20th August 2026
21st August 2026
22nd August 2026
23rd August 2026
24th August 2026
25th August 2026
26th August 2026
27th August 2026
28th August 2026
29th August 2026
30th August 2026
31st August 2026
1st September 2026
2nd September 2026
3rd September 2026
4th September 2026
5th September 2026
6th September 2026
7th September 2026
8th September 2026
9th September 2026
10th September 2026
11th September 2026
12th September 2026
13th September 2026
14th September 2026
15th September 2026
16th September 2026
17th September 2026
18th September 2026
19th September 2026
20th September 2026
21st September 2026
22nd September 2026
23rd September 2026
24th September 2026
25th September 2026
26th September 2026
27th September 2026
28th September 2026
29th September 2026
30th September 2026
1st October 2026
2nd October 2026
3rd October 2026
4th October 2026
5th October 2026
6th October 2026
7th October 2026
8th October 2026
9th October 2026
10th October 2026
11th October 2026
12th October 2026
13th October 2026
14th October 2026
15th October 2026
16th October 2026
17th October 2026
18th October 2026
19th October 2026
20th October 2026
21st October 2026
22nd October 2026
23rd October 2026
24th October 2026
25th October 2026
26th October 2026
27th October 2026
28th October 2026
29th October 2026
30th October 2026
31st October 2026
1st November 2026
2nd November 2026
3rd November 2026
4th November 2026
5th November 2026
6th November 2026
7th November 2026
8th November 2026
9th November 2026
10th November 2026
11th November 2026
12th November 2026
13th November 2026
14th November 2026
15th November 2026
16th November 2026
17th November 2026
18th November 2026
19th November 2026
20th November 2026
21st November 2026
22nd November 2026
23rd November 2026
24th November 2026
25th November 2026
26th November 2026
27th November 2026
28th November 2026
29th November 2026
30th November 2026
1st December 2026
2nd December 2026
3rd December 2026
4th December 2026
5th December 2026
6th December 2026
7th December 2026
8th December 2026
9th December 2026
10th December 2026
11th December 2026
12th December 2026
13th December 2026
14th December 2026
15th December 2026
16th December 2026
17th December 2026
18th December 2026
19th December 2026
20th December 2026
21st December 2026
22nd December 2026
23rd December 2026
24th December 2026
25th December 2026
26th December 2026
27th December 2026
28th December 2026
29th December 2026
30th December 2026
31st December 2026

23AQI (US)

23AQI (US)

23AQI (US)

21AQI (US)

20AQI (US)

25AQI (US)

28AQI (US)

31AQI (US)

No. of days

Jan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.Total Days

202623AQI (US)

31
28
31
28
30
30
31
1
210

Highest AQI (US) recorded in

August

31AQI (US)

Lowest AQI (US) recorded in

May

20AQI (US)

202529AQI (US)

31
28
31
29
1
31
30
28
3
25
6
25
5
31
30
31
350
15

Highest AQI (US) recorded in

August

42AQI (US)

Lowest AQI (US) recorded in

March

20AQI (US)

202424AQI (US)

30
1
29
31
30
31
30
26
5
29
2
29
1
28
3
30
31
354
12

Highest AQI (US) recorded in

July

34AQI (US)

Lowest AQI (US) recorded in

May

17AQI (US)

202326AQI (US)

26
2
24
2
31
29
1
26
3
1
30
31
17
5
30
30
1
28
31
333
14
1

Highest AQI (US) recorded in

May

35AQI (US)

Lowest AQI (US) recorded in

December

14AQI (US)

202227AQI (US)

29
1
21
1
30
1
14
2
1
31
27
3
21
2
26
3
31
30
30
292
11
1

Highest AQI (US) recorded in

April

35AQI (US)

Lowest AQI (US) recorded in

November

23AQI (US)

202133AQI (US)

28
2
22
6
27
4
24
3
28
20
6
20
10
14
16
1
24
6
31
29
1
30
1
297
55
1

Highest AQI (US) recorded in

August

55AQI (US)

Lowest AQI (US) recorded in

May

22AQI (US)

202036AQI (US)

3
3
5
1
13
5
25
2
29
1
20
8
19
10
20
10
1
29
30
1
193
41
1

Highest AQI (US) recorded in

March

56AQI (US)

Lowest AQI (US) recorded in

November

24AQI (US)

Most & Least Polluted Years Over the Last 7 Years

Most Polluted Year Recorded
2020(Avg.)
36AQI (US)
Least Polluted Year Recorded
2026(Avg.)
23AQI (US)

Boulder's annual 2026 AQI (US) (23) shows an average percentage change of -19.6% (improved AQI (US)) compared to previous years: 2020 (36), 2021 (33), 2022 (27), 2023 (26), 2024 (24), 2025 (29).