Chester, Illinois, 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
Chester, Illinois, United States
2022
2023
2024
2025
2026
AQI
.
Days
AQI Trends: Highest and Lowest
Highest AQI recorded on
1st Aug 2025
89AQILowest AQI recorded on
27th Aug 2023
21AQISame Day Analysis (6th August):
On this day, AQI across the 5 years varied significantly: 2026 ranks 3rd highest AQI at 39 of Good air quality, showing improvement over 2025 and 2024 on the same day.
Day & Night AQI Trend: 6th Aug - 7th Aug 2026
Chester, Illinois, United States
AQI
Day
Night
.
5 AM6th Aug 2026
8 PM
4 AM7th Aug 2026
Day time
Avg. Highest Time
9AM6th Aug
50AQI
Avg. Lowest Time
6PM6th Aug
23AQI
Night time
Avg. Highest Time
12AM7th Aug
52AQI
Avg. Lowest Time
11PM6th Aug
21AQI
In the last 24 hours,
Chester's AQI reached its highest point of 52 at 12 AM during the Night, while the lowest point, 21, was recorded at 11 PM during the Night between 6th Aug and 7th Aug 2026.
Day & Night AQI Trend : Jul - Aug 2026
Chester, Illinois, United States
JulAug
09th - 10th10th - 11th11th - 12th12th - 13th13th - 14th14th - 15th15th - 16th16th - 17th17th - 18th18th - 19th19th - 20th20th - 21st21st - 22nd22nd - 23rd23rd - 24th24th - 25th25th - 26th26th - 27th27th - 28th28th - 29th29th - 30th30th - 31st31st - 01st01st - 02nd02nd - 03rd03rd - 04th04th - 05th05th - 06th06th - 07th07th
Day
Night
9th Jul 2026425 AMAQI
9th Jul 2026306 AMAQI
9th Jul 2026287 AMAQI
9th Jul 2026248 AMAQI
9th Jul 2026319 AMAQI
9th Jul 20262810 AMAQI
9th Jul 20262511 AMAQI
9th Jul 20263212 PMAQI
9th Jul 2026281 PMAQI
9th Jul 2026232 PMAQI
9th Jul 2026343 PMAQI
9th Jul 2026344 PMAQI
9th Jul 2026305 PMAQI
9th Jul 2026386 PMAQI
9th Jul 2026127 PMAQI
9th Jul 2026338 PMAQI
9th Jul 2026389 PMAQI
9th Jul 20262410 PMAQI
9th Jul 20262811 PMAQI
10th Jul 20262712 AMAQI
10th Jul 2026261 AMAQI
10th Jul 2026312 AMAQI
10th Jul 2026153 AMAQI
10th Jul 2026204 AMAQI
27°C22/33°C
10th Jul 2026255 AMAQI
10th Jul 2026106 AMAQI
10th Jul 2026187 AMAQI
10th Jul 2026388 AMAQI
10th Jul 2026249 AMAQI
10th Jul 20262610 AMAQI
10th Jul 20264211 AMAQI
10th Jul 20263812 PMAQI
10th Jul 2026271 PMAQI
10th Jul 2026402 PMAQI
10th Jul 2026413 PMAQI
10th Jul 2026344 PMAQI
10th Jul 2026345 PMAQI
10th Jul 2026266 PMAQI
10th Jul 2026227 PMAQI
10th Jul 2026278 PMAQI
10th Jul 2026319 PMAQI
10th Jul 20262510 PMAQI
10th Jul 20262711 PMAQI
11th Jul 20262712 AMAQI
11th Jul 2026201 AMAQI
11th Jul 2026252 AMAQI
11th Jul 2026173 AMAQI
11th Jul 2026154 AMAQI
26°C23/33°C
11th Jul 2026165 AMAQI
11th Jul 2026176 AMAQI
11th Jul 2026197 AMAQI
11th Jul 2026168 AMAQI
11th Jul 2026169 AMAQI
11th Jul 20262510 AMAQI
11th Jul 20262111 AMAQI
11th Jul 20262012 PMAQI
11th Jul 2026231 PMAQI
11th Jul 2026182 PMAQI
11th Jul 2026253 PMAQI
11th Jul 2026204 PMAQI
11th Jul 2026205 PMAQI
11th Jul 2026236 PMAQI
11th Jul 2026197 PMAQI
11th Jul 2026328 PMAQI
11th Jul 2026199 PMAQI
11th Jul 20261910 PMAQI
11th Jul 20262411 PMAQI
12th Jul 20262112 AMAQI
12th Jul 2026251 AMAQI
12th Jul 2026162 AMAQI
12th Jul 2026103 AMAQI
12th Jul 202684 AMAQI
24°C20/29°C
12th Jul 2026145 AMAQI
12th Jul 2026176 AMAQI
12th Jul 2026147 AMAQI
12th Jul 2026148 AMAQI
12th Jul 2026149 AMAQI
12th Jul 20261810 AMAQI
12th Jul 20262111 AMAQI
12th Jul 20261712 PMAQI
12th Jul 2026141 PMAQI
12th Jul 2026142 PMAQI
12th Jul 2026163 PMAQI
12th Jul 2026164 PMAQI
12th Jul 2026165 PMAQI
12th Jul 2026256 PMAQI
12th Jul 2026187 PMAQI
12th Jul 2026108 PMAQI
12th Jul 2026279 PMAQI
12th Jul 20262410 PMAQI
12th Jul 20263311 PMAQI
13th Jul 20262412 AMAQI
13th Jul 2026271 AMAQI
13th Jul 2026242 AMAQI
13th Jul 2026223 AMAQI
13th Jul 2026214 AMAQI
26°C21/32°C
13th Jul 2026265 AMAQI
13th Jul 2026246 AMAQI
13th Jul 2026247 AMAQI
13th Jul 2026228 AMAQI
13th Jul 2026269 AMAQI
13th Jul 20262910 AMAQI
13th Jul 20263811 AMAQI
13th Jul 20263712 PMAQI
13th Jul 2026361 PMAQI
13th Jul 2026322 PMAQI
13th Jul 2026323 PMAQI
13th Jul 2026324 PMAQI
13th Jul 2026305 PMAQI
13th Jul 2026276 PMAQI
13th Jul 2026267 PMAQI
13th Jul 2026268 PMAQI
13th Jul 2026249 PMAQI
13th Jul 20262710 PMAQI
13th Jul 20264211 PMAQI
14th Jul 20264212 AMAQI
14th Jul 2026281 AMAQI
14th Jul 2026272 AMAQI
14th Jul 2026303 AMAQI
14th Jul 2026274 AMAQI
26°C20/32°C
14th Jul 2026235 AMAQI
14th Jul 2026256 AMAQI
14th Jul 2026307 AMAQI
14th Jul 2026348 AMAQI
14th Jul 2026329 AMAQI
14th Jul 20264010 AMAQI
14th Jul 20264511 AMAQI
14th Jul 20264512 PMAQI
14th Jul 2026441 PMAQI
14th Jul 2026402 PMAQI
14th Jul 2026363 PMAQI
14th Jul 2026354 PMAQI
14th Jul 2026265 PMAQI
14th Jul 2026286 PMAQI
14th Jul 2026197 PMAQI
14th Jul 2026188 PMAQI
14th Jul 2026189 PMAQI
14th Jul 20262110 PMAQI
14th Jul 20261811 PMAQI
15th Jul 20261912 AMAQI
15th Jul 2026401 AMAQI
15th Jul 2026292 AMAQI
15th Jul 2026263 AMAQI
15th Jul 2026274 AMAQI
27°C20/33°C
15th Jul 2026265 AMAQI
15th Jul 2026266 AMAQI
15th Jul 2026267 AMAQI
15th Jul 2026308 AMAQI
15th Jul 2026409 AMAQI
15th Jul 20266810 AMAQI
15th Jul 20266011 AMAQI
15th Jul 20265212 PMAQI
15th Jul 2026421 PMAQI
15th Jul 2026322 PMAQI
15th Jul 2026313 PMAQI
15th Jul 2026384 PMAQI
15th Jul 2026365 PMAQI
15th Jul 2026326 PMAQI
15th Jul 2026307 PMAQI
15th Jul 2026308 PMAQI
15th Jul 2026429 PMAQI
15th Jul 20264010 PMAQI
15th Jul 20263611 PMAQI
16th Jul 20263012 AMAQI
16th Jul 2026281 AMAQI
16th Jul 2026312 AMAQI
16th Jul 2026283 AMAQI
16th Jul 2026274 AMAQI
27°C21/34°C
16th Jul 2026325 AMAQI
16th Jul 2026306 AMAQI
16th Jul 2026347 AMAQI
16th Jul 2026318 AMAQI
16th Jul 2026429 AMAQI
16th Jul 20264410 AMAQI
16th Jul 20265011 AMAQI
16th Jul 20264412 PMAQI
16th Jul 2026381 PMAQI
16th Jul 2026342 PMAQI
16th Jul 2026183 PMAQI
16th Jul 2026164 PMAQI
16th Jul 2026165 PMAQI
16th Jul 2026166 PMAQI
16th Jul 2026157 PMAQI
16th Jul 2026168 PMAQI
16th Jul 2026159 PMAQI
16th Jul 20261610 PMAQI
16th Jul 20261411 PMAQI
17th Jul 20261412 AMAQI
17th Jul 2026151 AMAQI
17th Jul 2026292 AMAQI
17th Jul 2026293 AMAQI
17th Jul 2026424 AMAQI
27°C22/33°C
17th Jul 2026485 AMAQI
17th Jul 2026466 AMAQI
17th Jul 2026467 AMAQI
17th Jul 2026428 AMAQI
17th Jul 2026449 AMAQI
17th Jul 20264010 AMAQI
17th Jul 20263811 AMAQI
17th Jul 20264012 PMAQI
17th Jul 2026421 PMAQI
17th Jul 2026462 PMAQI
17th Jul 2026463 PMAQI
17th Jul 2026534 PMAQI
17th Jul 2026465 PMAQI
17th Jul 2026526 PMAQI
17th Jul 2026487 PMAQI
17th Jul 2026448 PMAQI
17th Jul 2026469 PMAQI
17th Jul 20264010 PMAQI
17th Jul 20264411 PMAQI
18th Jul 20264212 AMAQI
18th Jul 2026421 AMAQI
18th Jul 2026422 AMAQI
18th Jul 2026423 AMAQI
18th Jul 2026464 AMAQI
27°C23/33°C
18th Jul 2026425 AMAQI
18th Jul 2026446 AMAQI
18th Jul 2026407 AMAQI
18th Jul 2026428 AMAQI
18th Jul 2026429 AMAQI
18th Jul 20264610 AMAQI
18th Jul 20264411 AMAQI
18th Jul 20264412 PMAQI
18th Jul 2026441 PMAQI
18th Jul 2026482 PMAQI
18th Jul 2026463 PMAQI
18th Jul 2026444 PMAQI
18th Jul 2026425 PMAQI
18th Jul 2026426 PMAQI
18th Jul 2026447 PMAQI
18th Jul 2026448 PMAQI
18th Jul 2026469 PMAQI
18th Jul 20264410 PMAQI
18th Jul 20264611 PMAQI
19th Jul 20264812 AMAQI
19th Jul 2026421 AMAQI
19th Jul 2026442 AMAQI
19th Jul 2026463 AMAQI
19th Jul 2026444 AMAQI
29°C23/35°C
19th Jul 2026445 AMAQI
19th Jul 2026426 AMAQI
19th Jul 2026447 AMAQI
19th Jul 2026428 AMAQI
19th Jul 2026429 AMAQI
19th Jul 20263810 AMAQI
19th Jul 20264411 AMAQI
19th Jul 20264212 PMAQI
19th Jul 2026441 PMAQI
19th Jul 2026422 PMAQI
19th Jul 2026483 PMAQI
19th Jul 2026384 PMAQI
19th Jul 2026465 PMAQI
19th Jul 2026386 PMAQI
19th Jul 2026547 PMAQI
19th Jul 2026408 PMAQI
19th Jul 2026579 PMAQI
19th Jul 20266510 PMAQI
19th Jul 20267111 PMAQI
20th Jul 20268412 AMAQI
20th Jul 2026901 AMAQI
20th Jul 2026982 AMAQI
20th Jul 20261013 AMAQI
20th Jul 2026534 AMAQI
27°C25/32°C
20th Jul 2026745 AMAQI
20th Jul 2026876 AMAQI
20th Jul 20261007 AMAQI
20th Jul 20261148 AMAQI
20th Jul 20261229 AMAQI
20th Jul 202612210 AMAQI
20th Jul 202611411 AMAQI
20th Jul 20269212 PMAQI
20th Jul 2026811 PMAQI
20th Jul 2026712 PMAQI
20th Jul 2026673 PMAQI
20th Jul 2026654 PMAQI
20th Jul 2026645 PMAQI
20th Jul 2026676 PMAQI
20th Jul 2026667 PMAQI
20th Jul 2026698 PMAQI
20th Jul 2026639 PMAQI
20th Jul 20266011 PMAQI
21st Jul 20266212 AMAQI
21st Jul 2026561 AMAQI
21st Jul 2026512 AMAQI
21st Jul 2026443 AMAQI
21st Jul 2026544 AMAQI
28°C22/34°C
21st Jul 2026465 AMAQI
21st Jul 2026486 AMAQI
21st Jul 2026487 AMAQI
21st Jul 2026428 AMAQI
21st Jul 2026449 AMAQI
21st Jul 20264810 AMAQI
21st Jul 20265111 AMAQI
21st Jul 20265112 PMAQI
21st Jul 2026501 PMAQI
21st Jul 2026442 PMAQI
21st Jul 2026443 PMAQI
21st Jul 2026464 PMAQI
21st Jul 2026515 PMAQI
21st Jul 2026526 PMAQI
21st Jul 2026447 PMAQI
21st Jul 2026488 PMAQI
21st Jul 2026469 PMAQI
21st Jul 20265210 PMAQI
21st Jul 20265211 PMAQI
22nd Jul 20265012 AMAQI
22nd Jul 2026461 AMAQI
22nd Jul 2026442 AMAQI
22nd Jul 2026423 AMAQI
22nd Jul 2026484 AMAQI
29°C24/36°C
22nd Jul 2026465 AMAQI
22nd Jul 2026386 AMAQI
22nd Jul 2026507 AMAQI
22nd Jul 2026428 AMAQI
22nd Jul 2026429 AMAQI
22nd Jul 20264210 AMAQI
22nd Jul 20264211 AMAQI
22nd Jul 20264212 PMAQI
22nd Jul 2026461 PMAQI
22nd Jul 2026392 PMAQI
22nd Jul 2026483 PMAQI
22nd Jul 2026294 PMAQI
22nd Jul 2026485 PMAQI
22nd Jul 2026526 PMAQI
22nd Jul 2026447 PMAQI
22nd Jul 2026368 PMAQI
22nd Jul 2026529 PMAQI
22nd Jul 20263610 PMAQI
22nd Jul 20263811 PMAQI
23rd Jul 20265212 AMAQI
23rd Jul 2026521 AMAQI
23rd Jul 2026522 AMAQI
23rd Jul 2026403 AMAQI
23rd Jul 2026384 AMAQI
23°C18/28°C
23rd Jul 2026495 AMAQI
23rd Jul 2026496 AMAQI
23rd Jul 2026337 AMAQI
23rd Jul 2026298 AMAQI
23rd Jul 2026369 AMAQI
23rd Jul 20264610 AMAQI
23rd Jul 20264611 AMAQI
23rd Jul 20263812 PMAQI
23rd Jul 2026521 PMAQI
23rd Jul 2026272 PMAQI
23rd Jul 2026423 PMAQI
23rd Jul 2026294 PMAQI
23rd Jul 2026495 PMAQI
23rd Jul 2026246 PMAQI
23rd Jul 2026517 PMAQI
23rd Jul 2026408 PMAQI
23rd Jul 2026259 PMAQI
23rd Jul 20262110 PMAQI
23rd Jul 20263311 PMAQI
24th Jul 20263312 AMAQI
24th Jul 2026421 AMAQI
24th Jul 2026322 AMAQI
24th Jul 2026293 AMAQI
24th Jul 2026214 AMAQI
22°C17/27°C
24th Jul 2026385 AMAQI
24th Jul 2026326 AMAQI
24th Jul 2026257 AMAQI
24th Jul 2026258 AMAQI
24th Jul 2026289 AMAQI
24th Jul 20264010 AMAQI
24th Jul 20264611 AMAQI
24th Jul 20264212 PMAQI
24th Jul 2026291 PMAQI
24th Jul 2026542 PMAQI
24th Jul 2026333 PMAQI
24th Jul 2026364 PMAQI
24th Jul 2026385 PMAQI
24th Jul 2026406 PMAQI
24th Jul 2026257 PMAQI
24th Jul 2026348 PMAQI
24th Jul 2026469 PMAQI
24th Jul 20263310 PMAQI
24th Jul 20263811 PMAQI
25th Jul 20264212 AMAQI
25th Jul 2026461 AMAQI
25th Jul 2026402 AMAQI
25th Jul 2026403 AMAQI
25th Jul 2026404 AMAQI
22°C17/29°C
25th Jul 2026445 AMAQI
25th Jul 2026446 AMAQI
25th Jul 2026387 AMAQI
25th Jul 2026468 AMAQI
25th Jul 2026539 AMAQI
25th Jul 20265410 AMAQI
25th Jul 20264911 AMAQI
25th Jul 20265112 PMAQI
25th Jul 2026481 PMAQI
25th Jul 2026492 PMAQI
25th Jul 2026523 PMAQI
25th Jul 2026504 PMAQI
25th Jul 2026485 PMAQI
25th Jul 2026486 PMAQI
25th Jul 2026507 PMAQI
25th Jul 2026488 PMAQI
25th Jul 2026509 PMAQI
25th Jul 20265010 PMAQI
25th Jul 20265211 PMAQI
26th Jul 20265112 AMAQI
26th Jul 2026501 AMAQI
26th Jul 2026482 AMAQI
26th Jul 2026503 AMAQI
26th Jul 2026564 AMAQI
26°C20/34°C
26th Jul 2026535 AMAQI
26th Jul 2026466 AMAQI
26th Jul 2026467 AMAQI
26th Jul 2026468 AMAQI
26th Jul 2026449 AMAQI
26th Jul 20264610 AMAQI
26th Jul 20264611 AMAQI
26th Jul 20264612 PMAQI
26th Jul 2026531 PMAQI
26th Jul 2026422 PMAQI
26th Jul 2026423 PMAQI
26th Jul 2026484 PMAQI
26th Jul 2026465 PMAQI
26th Jul 2026426 PMAQI
26th Jul 2026467 PMAQI
26th Jul 2026488 PMAQI
26th Jul 2026449 PMAQI
26th Jul 20264410 PMAQI
26th Jul 20264211 PMAQI
27th Jul 20264212 AMAQI
27th Jul 2026421 AMAQI
27th Jul 2026422 AMAQI
27th Jul 2026533 AMAQI
27th Jul 2026424 AMAQI
30°C24/38°C
27th Jul 2026425 AMAQI
27th Jul 2026546 AMAQI
27th Jul 2026527 AMAQI
27th Jul 2026408 AMAQI
27th Jul 2026409 AMAQI
27th Jul 20264210 AMAQI
27th Jul 20264611 AMAQI
27th Jul 20264212 PMAQI
27th Jul 2026441 PMAQI
27th Jul 2026502 PMAQI
27th Jul 2026463 PMAQI
27th Jul 2026494 PMAQI
27th Jul 2026535 PMAQI
27th Jul 2026506 PMAQI
27th Jul 2026517 PMAQI
27th Jul 2026508 PMAQI
27th Jul 2026519 PMAQI
27th Jul 20264810 PMAQI
27th Jul 20265211 PMAQI
28th Jul 20265012 AMAQI
28th Jul 2026501 AMAQI
28th Jul 2026502 AMAQI
28th Jul 2026463 AMAQI
28th Jul 2026494 AMAQI
30°C24/37°C
28th Jul 2026485 AMAQI
28th Jul 2026486 AMAQI
28th Jul 2026487 AMAQI
28th Jul 2026468 AMAQI
28th Jul 2026509 AMAQI
28th Jul 20265110 AMAQI
28th Jul 20265011 AMAQI
28th Jul 20265212 PMAQI
28th Jul 2026531 PMAQI
28th Jul 2026532 PMAQI
28th Jul 2026563 PMAQI
28th Jul 2026554 PMAQI
28th Jul 2026575 PMAQI
28th Jul 2026586 PMAQI
28th Jul 2026537 PMAQI
28th Jul 2026558 PMAQI
28th Jul 2026549 PMAQI
28th Jul 20265210 PMAQI
28th Jul 20265111 PMAQI
29th Jul 20265012 AMAQI
29th Jul 2026511 AMAQI
29th Jul 2026442 AMAQI
29th Jul 2026423 AMAQI
29th Jul 2026494 AMAQI
30°C25/36°C
29th Jul 2026485 AMAQI
29th Jul 2026426 AMAQI
29th Jul 2026467 AMAQI
29th Jul 2026408 AMAQI
29th Jul 2026469 AMAQI
29th Jul 20264410 AMAQI
29th Jul 20264011 AMAQI
29th Jul 20263612 PMAQI
29th Jul 2026421 PMAQI
29th Jul 2026442 PMAQI
29th Jul 2026383 PMAQI
29th Jul 2026424 PMAQI
29th Jul 2026255 PMAQI
29th Jul 2026426 PMAQI
29th Jul 2026297 PMAQI
29th Jul 2026238 PMAQI
29th Jul 2026549 PMAQI
29th Jul 20264610 PMAQI
29th Jul 20263811 PMAQI
30th Jul 20265012 AMAQI
30th Jul 2026311 AMAQI
30th Jul 2026462 AMAQI
30th Jul 2026443 AMAQI
30th Jul 2026444 AMAQI
26°C19/32°C
30th Jul 2026505 AMAQI
30th Jul 2026366 AMAQI
30th Jul 2026467 AMAQI
30th Jul 2026428 AMAQI
30th Jul 2026469 AMAQI
30th Jul 20264810 AMAQI
30th Jul 20264011 AMAQI
30th Jul 20264612 PMAQI
30th Jul 2026211 PMAQI
30th Jul 2026422 PMAQI
30th Jul 2026443 PMAQI
30th Jul 2026424 PMAQI
30th Jul 2026425 PMAQI
30th Jul 2026426 PMAQI
30th Jul 2026467 PMAQI
30th Jul 2026488 PMAQI
30th Jul 2026449 PMAQI
30th Jul 20264010 PMAQI
30th Jul 20264611 PMAQI
31st Jul 20264012 AMAQI
31st Jul 2026461 AMAQI
31st Jul 2026422 AMAQI
31st Jul 2026463 AMAQI
31st Jul 2026464 AMAQI
26°C19/32°C
31st Jul 2026425 AMAQI
31st Jul 2026486 AMAQI
31st Jul 2026487 AMAQI
31st Jul 2026508 AMAQI
31st Jul 2026489 AMAQI
31st Jul 20265210 AMAQI
31st Jul 20264811 AMAQI
31st Jul 20264412 PMAQI
31st Jul 2026491 PMAQI
31st Jul 2026482 PMAQI
31st Jul 2026343 PMAQI
31st Jul 2026324 PMAQI
31st Jul 2026445 PMAQI
31st Jul 2026426 PMAQI
31st Jul 2026487 PMAQI
31st Jul 2026428 PMAQI
31st Jul 2026489 PMAQI
31st Jul 20264610 PMAQI
31st Jul 20264611 PMAQI
1st Aug 20265012 AMAQI
1st Aug 2026421 AMAQI
1st Aug 2026442 AMAQI
1st Aug 2026343 AMAQI
1st Aug 2026364 AMAQI
23°C21/30°C
1st Aug 2026465 AMAQI
1st Aug 2026466 AMAQI
1st Aug 2026327 AMAQI
1st Aug 2026368 AMAQI
1st Aug 2026279 AMAQI
1st Aug 20264410 AMAQI
1st Aug 20265111 AMAQI
1st Aug 20265012 PMAQI
1st Aug 2026481 PMAQI
1st Aug 2026462 PMAQI
1st Aug 2026463 PMAQI
1st Aug 2026504 PMAQI
1st Aug 2026505 PMAQI
1st Aug 2026346 PMAQI
1st Aug 2026347 PMAQI
1st Aug 2026518 PMAQI
1st Aug 2026259 PMAQI
1st Aug 20263110 PMAQI
1st Aug 20263111 PMAQI
2nd Aug 20262912 AMAQI
2nd Aug 2026231 AMAQI
2nd Aug 2026272 AMAQI
2nd Aug 2026343 AMAQI
2nd Aug 2026294 AMAQI
22°C20/24°C
2nd Aug 2026425 AMAQI
2nd Aug 2026236 AMAQI
2nd Aug 2026407 AMAQI
2nd Aug 2026408 AMAQI
2nd Aug 2026429 AMAQI
2nd Aug 20264610 AMAQI
2nd Aug 20264211 AMAQI
2nd Aug 20264612 PMAQI
2nd Aug 2026441 PMAQI
2nd Aug 2026482 PMAQI
2nd Aug 2026423 PMAQI
2nd Aug 2026444 PMAQI
2nd Aug 2026465 PMAQI
2nd Aug 2026446 PMAQI
2nd Aug 2026427 PMAQI
2nd Aug 2026468 PMAQI
2nd Aug 2026429 PMAQI
2nd Aug 20264410 PMAQI
2nd Aug 20264011 PMAQI
3rd Aug 20264212 AMAQI
3rd Aug 2026401 AMAQI
3rd Aug 2026402 AMAQI
3rd Aug 2026463 AMAQI
3rd Aug 2026424 AMAQI
23°C21/28°C
3rd Aug 2026445 AMAQI
3rd Aug 2026466 AMAQI
3rd Aug 2026487 AMAQI
3rd Aug 2026488 AMAQI
3rd Aug 2026469 AMAQI
3rd Aug 20264810 AMAQI
3rd Aug 20264211 AMAQI
3rd Aug 20264412 PMAQI
3rd Aug 2026481 PMAQI
3rd Aug 2026482 PMAQI
3rd Aug 2026463 PMAQI
3rd Aug 2026534 PMAQI
3rd Aug 2026515 PMAQI
3rd Aug 2026506 PMAQI
3rd Aug 2026467 PMAQI
3rd Aug 2026488 PMAQI
3rd Aug 2026469 PMAQI
3rd Aug 20264410 PMAQI
3rd Aug 20264011 PMAQI
4th Aug 20264212 AMAQI
4th Aug 2026441 AMAQI
4th Aug 2026482 AMAQI
4th Aug 2026463 AMAQI
4th Aug 2026484 AMAQI
24°C17/31°C
4th Aug 2026465 AMAQI
4th Aug 2026466 AMAQI
4th Aug 2026447 AMAQI
4th Aug 2026468 AMAQI
4th Aug 2026489 AMAQI
4th Aug 20264910 AMAQI
4th Aug 20265011 AMAQI
4th Aug 20265012 PMAQI
4th Aug 2026481 PMAQI
4th Aug 2026482 PMAQI
4th Aug 2026513 PMAQI
4th Aug 2026444 PMAQI
4th Aug 2026445 PMAQI
4th Aug 2026426 PMAQI
4th Aug 2026447 PMAQI
4th Aug 2026468 PMAQI
4th Aug 2026469 PMAQI
4th Aug 20264610 PMAQI
4th Aug 20264811 PMAQI
5th Aug 20265312 AMAQI
5th Aug 2026521 AMAQI
5th Aug 2026522 AMAQI
5th Aug 2026513 AMAQI
5th Aug 2026514 AMAQI
25°C19/32°C
5th Aug 2026485 AMAQI
5th Aug 2026446 AMAQI
5th Aug 2026497 AMAQI
5th Aug 2026488 AMAQI
5th Aug 2026489 AMAQI
5th Aug 20265010 AMAQI
5th Aug 20264811 AMAQI
5th Aug 20265012 PMAQI
5th Aug 2026461 PMAQI
5th Aug 2026522 PMAQI
5th Aug 2026503 PMAQI
5th Aug 2026464 PMAQI
5th Aug 2026505 PMAQI
5th Aug 2026466 PMAQI
5th Aug 2026427 PMAQI
5th Aug 2026468 PMAQI
5th Aug 2026449 PMAQI
5th Aug 20264610 PMAQI
5th Aug 20264611 PMAQI
6th Aug 20264612 AMAQI
6th Aug 2026481 AMAQI
6th Aug 2026482 AMAQI
6th Aug 2026463 AMAQI
6th Aug 2026484 AMAQI
25°C19/33°C
6th Aug 2026445 AMAQI
6th Aug 2026426 AMAQI
6th Aug 2026447 AMAQI
6th Aug 2026488 AMAQI
6th Aug 2026509 AMAQI
6th Aug 20262710 AMAQI
6th Aug 20263211 AMAQI
6th Aug 20264012 PMAQI
6th Aug 2026311 PMAQI
6th Aug 2026232 PMAQI
6th Aug 2026323 PMAQI
6th Aug 2026384 PMAQI
6th Aug 2026235 PMAQI
6th Aug 2026236 PMAQI
6th Aug 2026447 PMAQI
6th Aug 2026468 PMAQI
6th Aug 2026449 PMAQI
6th Aug 20264910 PMAQI
6th Aug 20262111 PMAQI
7th Aug 20265212 AMAQI
7th Aug 2026471 AMAQI
7th Aug 2026342 AMAQI
7th Aug 2026463 AMAQI
7th Aug 2026504 AMAQI
24°C22/28°C
7th Aug 2026425 AMAQI
5 AM7th Aug 2026466 AMAQI
7th Aug 2026387 AMAQI
7th Aug 2026388 AMAQI
7th Aug 2026569 AMAQI
7th Aug 20264210 AMAQI
7th Aug 20264211 AMAQI
7th Aug 20264412 PMAQI
12 PM7th Aug 2026441 PMAQI
7th Aug 2026442 PMAQI
7th Aug 2026483 PMAQI
7th Aug 2026534 PMAQI
7th Aug 2026535 PMAQI
7th Aug 2026466 PMAQI
7th Aug 2026447 PMAQI
7th Aug 2026428 PMAQI
8 PM7th Aug 2026449 PMAQI
7th Aug 20263810 PMAQI
7th Aug 20264211 PMAQI
12 AM
4 AM
26°C20/33°C
Day time
Avg. Highest Time
10 AM - 12 PM
45AQI
3 hours / Day
90 hours / Month
Avg. Lowest Time
6 AM - 8 AM
40AQI
3 hours / Day
90 hours / Month
In the last 30 days, during the daytime, the highest AQI was between 10 AM to 12 PM (Avg. 45), while the lowest AQI was between 6 AM to 8 AM (Avg. 40).
Night time
Avg. Highest Time
12 AM - 2 AM
42AQI
3 hours / Day
90 hours / Month
Avg. Lowest Time
3 AM - 4 AM
39AQI
2 hours / Day
60 hours / Month
In the last 30 days, during the daytime, the highest AQI was between 12 AM to 2 AM (Avg. 42), while the lowest AQI was between 3 AM to 4 AM (Avg. 39).
2026 Days Vs Air Quality
Chester, Illinois, United States
2026
96%
207
4%
8
Total number of days with different AQI categories in last 219 days in 2026 (146 days remaining)
Good
207 DaysModerate
8 DaysPoor
0 DaysUnhealthy
0 DaysSevere
0 DaysHazardous
0 DaysUnder WHO’s Safe Air Quality Limits: 96%
Health Risk Level:
Very Low
In 2026, 96% of 219 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
Chester, Illinois, 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
40AQI (US)
40AQI (US)
2nd January 2026
50AQI (US)
50AQI (US)
3rd January 2026
36AQI (US)
36AQI (US)
4th January 2026
46AQI (US)
46AQI (US)
5th January 2026
46AQI (US)
46AQI (US)
6th January 2026
41AQI (US)
41AQI (US)
7th January 2026
39AQI (US)
39AQI (US)
8th January 2026
40AQI (US)
40AQI (US)
9th January 2026
20AQI (US)
20AQI (US)
10th January 2026
22AQI (US)
22AQI (US)
11th January 2026
15AQI (US)
15AQI (US)
12th January 2026
23AQI (US)
23AQI (US)
13th January 2026
38AQI (US)
38AQI (US)
14th January 2026
11AQI (US)
11AQI (US)
15th January 2026
15AQI (US)
15AQI (US)
16th January 2026
22AQI (US)
22AQI (US)
17th January 2026
12AQI (US)
12AQI (US)
18th January 2026
16AQI (US)
16AQI (US)
19th January 2026
14AQI (US)
14AQI (US)
20th January 2026
31AQI (US)
31AQI (US)
21st January 2026
41AQI (US)
41AQI (US)
22nd January 2026
43AQI (US)
43AQI (US)
23rd January 2026
54AQI (US)
54AQI (US)
24th January 2026
28AQI (US)
28AQI (US)
25th January 2026
32AQI (US)
32AQI (US)
26th January 2026
36AQI (US)
36AQI (US)
27th January 2026
27AQI (US)
27AQI (US)
28th January 2026
31AQI (US)
31AQI (US)
29th January 2026
44AQI (US)
44AQI (US)
30th January 2026
54AQI (US)
54AQI (US)
31st January 2026
30AQI (US)
30AQI (US)
1st February 2026
36AQI (US)
36AQI (US)
2nd February 2026
46AQI (US)
46AQI (US)
3rd February 2026
39AQI (US)
39AQI (US)
4th February 2026
35AQI (US)
35AQI (US)
5th February 2026
49AQI (US)
49AQI (US)
6th February 2026
40AQI (US)
40AQI (US)
7th February 2026
30AQI (US)
30AQI (US)
8th February 2026
24AQI (US)
24AQI (US)
9th February 2026
47AQI (US)
47AQI (US)
10th February 2026
40AQI (US)
40AQI (US)
11th February 2026
29AQI (US)
29AQI (US)
12th February 2026
51AQI (US)
51AQI (US)
13th February 2026
38AQI (US)
38AQI (US)
14th February 2026
44AQI (US)
44AQI (US)
15th February 2026
30AQI (US)
30AQI (US)
16th February 2026
36AQI (US)
36AQI (US)
17th February 2026
36AQI (US)
36AQI (US)
18th February 2026
42AQI (US)
42AQI (US)
19th February 2026
41AQI (US)
41AQI (US)
20th February 2026
28AQI (US)
28AQI (US)
21st February 2026
24AQI (US)
24AQI (US)
22nd February 2026
23AQI (US)
23AQI (US)
23rd February 2026
27AQI (US)
27AQI (US)
24th February 2026
44AQI (US)
44AQI (US)
25th February 2026
45AQI (US)
45AQI (US)
26th February 2026
36AQI (US)
36AQI (US)
27th February 2026
41AQI (US)
41AQI (US)
28th February 2026
32AQI (US)
32AQI (US)
1st March 2026
28AQI (US)
28AQI (US)
2nd March 2026
38AQI (US)
38AQI (US)
3rd March 2026
30AQI (US)
30AQI (US)
4th March 2026
37AQI (US)
37AQI (US)
5th March 2026
27AQI (US)
27AQI (US)
6th March 2026
21AQI (US)
21AQI (US)
7th March 2026
30AQI (US)
30AQI (US)
8th March 2026
32AQI (US)
32AQI (US)
9th March 2026
34AQI (US)
34AQI (US)
10th March 2026
30AQI (US)
30AQI (US)
11th March 2026
33AQI (US)
33AQI (US)
12th March 2026
24AQI (US)
24AQI (US)
13th March 2026
31AQI (US)
31AQI (US)
14th March 2026
25AQI (US)
25AQI (US)
15th March 2026
26AQI (US)
26AQI (US)
16th March 2026
27AQI (US)
27AQI (US)
17th March 2026
29AQI (US)
29AQI (US)
18th March 2026
23AQI (US)
23AQI (US)
19th March 2026
51AQI (US)
51AQI (US)
20th March 2026
50AQI (US)
50AQI (US)
21st March 2026
41AQI (US)
41AQI (US)
22nd March 2026
42AQI (US)
42AQI (US)
23rd March 2026
32AQI (US)
32AQI (US)
24th March 2026
31AQI (US)
31AQI (US)
25th March 2026
49AQI (US)
49AQI (US)
26th March 2026
49AQI (US)
49AQI (US)
27th March 2026
27AQI (US)
27AQI (US)
28th March 2026
17AQI (US)
17AQI (US)
29th March 2026
20AQI (US)
20AQI (US)
30th March 2026
39AQI (US)
39AQI (US)
31st March 2026
36AQI (US)
36AQI (US)
1st April 2026
25AQI (US)
25AQI (US)
2nd April 2026
21AQI (US)
21AQI (US)
3rd April 2026
21AQI (US)
21AQI (US)
4th April 2026
29AQI (US)
29AQI (US)
5th April 2026
28AQI (US)
28AQI (US)
6th April 2026
29AQI (US)
29AQI (US)
7th April 2026
26AQI (US)
26AQI (US)
8th April 2026
45AQI (US)
45AQI (US)
9th April 2026
39AQI (US)
39AQI (US)
10th April 2026
32AQI (US)
32AQI (US)
11th April 2026
28AQI (US)
28AQI (US)
12th April 2026
34AQI (US)
34AQI (US)
13th April 2026
26AQI (US)
26AQI (US)
14th April 2026
33AQI (US)
33AQI (US)
15th April 2026
29AQI (US)
29AQI (US)
16th April 2026
21AQI (US)
21AQI (US)
17th April 2026
18th April 2026
21AQI (US)
21AQI (US)
19th April 2026
20AQI (US)
20AQI (US)
20th April 2026
19AQI (US)
19AQI (US)
21st April 2026
23AQI (US)
23AQI (US)
22nd April 2026
23rd April 2026
40AQI (US)
40AQI (US)
24th April 2026
21AQI (US)
21AQI (US)
25th April 2026
16AQI (US)
16AQI (US)
26th April 2026
23AQI (US)
23AQI (US)
27th April 2026
22AQI (US)
22AQI (US)
28th April 2026
20AQI (US)
20AQI (US)
29th April 2026
20AQI (US)
20AQI (US)
30th April 2026
27AQI (US)
27AQI (US)
1st May 2026
20AQI (US)
20AQI (US)
2nd May 2026
19AQI (US)
19AQI (US)
3rd May 2026
25AQI (US)
25AQI (US)
4th May 2026
37AQI (US)
37AQI (US)
5th May 2026
33AQI (US)
33AQI (US)
6th May 2026
22AQI (US)
22AQI (US)
7th May 2026
24AQI (US)
24AQI (US)
8th May 2026
27AQI (US)
27AQI (US)
9th May 2026
10th May 2026
24AQI (US)
24AQI (US)
11th May 2026
22AQI (US)
22AQI (US)
12th May 2026
31AQI (US)
31AQI (US)
13th May 2026
43AQI (US)
43AQI (US)
14th May 2026
27AQI (US)
27AQI (US)
15th May 2026
44AQI (US)
44AQI (US)
16th May 2026
48AQI (US)
48AQI (US)
17th May 2026
53AQI (US)
53AQI (US)
18th May 2026
50AQI (US)
50AQI (US)
19th May 2026
50AQI (US)
50AQI (US)
20th May 2026
45AQI (US)
45AQI (US)
21st May 2026
39AQI (US)
39AQI (US)
22nd May 2026
38AQI (US)
38AQI (US)
23rd May 2026
48AQI (US)
48AQI (US)
24th May 2026
39AQI (US)
39AQI (US)
25th May 2026
38AQI (US)
38AQI (US)
26th May 2026
33AQI (US)
33AQI (US)
27th May 2026
21AQI (US)
21AQI (US)
28th May 2026
37AQI (US)
37AQI (US)
29th May 2026
38AQI (US)
38AQI (US)
30th May 2026
27AQI (US)
27AQI (US)
31st May 2026
23AQI (US)
23AQI (US)
1st June 2026
23AQI (US)
23AQI (US)
2nd June 2026
26AQI (US)
26AQI (US)
3rd June 2026
36AQI (US)
36AQI (US)
4th June 2026
43AQI (US)
43AQI (US)
5th June 2026
36AQI (US)
36AQI (US)
6th June 2026
22AQI (US)
22AQI (US)
7th June 2026
26AQI (US)
26AQI (US)
8th June 2026
20AQI (US)
20AQI (US)
9th June 2026
21AQI (US)
21AQI (US)
10th June 2026
26AQI (US)
26AQI (US)
11th June 2026
20AQI (US)
20AQI (US)
12th June 2026
17AQI (US)
17AQI (US)
13th June 2026
19AQI (US)
19AQI (US)
14th June 2026
16AQI (US)
16AQI (US)
15th June 2026
17AQI (US)
17AQI (US)
16th June 2026
18AQI (US)
18AQI (US)
17th June 2026
38AQI (US)
38AQI (US)
18th June 2026
20AQI (US)
20AQI (US)
19th June 2026
21AQI (US)
21AQI (US)
20th June 2026
20AQI (US)
20AQI (US)
21st June 2026
18AQI (US)
18AQI (US)
22nd June 2026
16AQI (US)
16AQI (US)
23rd June 2026
17AQI (US)
17AQI (US)
24th June 2026
28AQI (US)
28AQI (US)
25th June 2026
17AQI (US)
17AQI (US)
26th June 2026
16AQI (US)
16AQI (US)
27th June 2026
20AQI (US)
20AQI (US)
28th June 2026
29AQI (US)
29AQI (US)
29th June 2026
34AQI (US)
34AQI (US)
30th June 2026
58AQI (US)
58AQI (US)
1st July 2026
47AQI (US)
47AQI (US)
2nd July 2026
37AQI (US)
37AQI (US)
3rd July 2026
23AQI (US)
23AQI (US)
4th July 2026
23AQI (US)
23AQI (US)
5th July 2026
26AQI (US)
26AQI (US)
6th July 2026
23AQI (US)
23AQI (US)
7th July 2026
23AQI (US)
23AQI (US)
8th July 2026
33AQI (US)
33AQI (US)
9th July 2026
31AQI (US)
31AQI (US)
10th July 2026
28AQI (US)
28AQI (US)
11th July 2026
21AQI (US)
21AQI (US)
12th July 2026
18AQI (US)
18AQI (US)
13th July 2026
28AQI (US)
28AQI (US)
14th July 2026
30AQI (US)
30AQI (US)
15th July 2026
36AQI (US)
36AQI (US)
16th July 2026
28AQI (US)
28AQI (US)
17th July 2026
41AQI (US)
41AQI (US)
18th July 2026
44AQI (US)
44AQI (US)
19th July 2026
46AQI (US)
46AQI (US)
20th July 2026
84AQI (US)
84AQI (US)
21st July 2026
49AQI (US)
49AQI (US)
22nd July 2026
43AQI (US)
43AQI (US)
23rd July 2026
40AQI (US)
40AQI (US)
24th July 2026
35AQI (US)
35AQI (US)
25th July 2026
47AQI (US)
47AQI (US)
26th July 2026
47AQI (US)
47AQI (US)
27th July 2026
47AQI (US)
47AQI (US)
28th July 2026
51AQI (US)
51AQI (US)
29th July 2026
42AQI (US)
42AQI (US)
30th July 2026
43AQI (US)
43AQI (US)
31st July 2026
45AQI (US)
45AQI (US)
1st August 2026
41AQI (US)
41AQI (US)
2nd August 2026
39AQI (US)
39AQI (US)
3rd August 2026
46AQI (US)
46AQI (US)
4th August 2026
46AQI (US)
46AQI (US)
5th August 2026
48AQI (US)
48AQI (US)
6th August 2026
39AQI (US)
39AQI (US)
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
32AQI (US)
37AQI (US)
33AQI (US)
26AQI (US)
34AQI (US)
25AQI (US)
37AQI (US)
43AQI (US)
No. of days
Jan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.Total Days
202632AQI (US)
29
2
27
1
30
1
28
29
1
29
1
29
2
6
207
8
Highest AQI (US) recorded in
August43AQI (US)
Lowest AQI (US) recorded in
June25AQI (US)
202537AQI (US)
29
2
28
27
3
1
29
1
29
2
16
14
24
7
21
10
17
13
20
11
25
5
25
6
290
74
1
Highest AQI (US) recorded in
June47AQI (US)
Lowest AQI (US) recorded in
January27AQI (US)
202431AQI (US)
30
1
26
3
31
30
31
28
1
29
2
29
2
30
27
4
30
31
352
13
Highest AQI (US) recorded in
October37AQI (US)
Lowest AQI (US) recorded in
November24AQI (US)
202338AQI (US)
27
4
28
30
1
27
3
25
6
8
22
28
3
23
8
26
4
27
4
29
31
309
55
Highest AQI (US) recorded in
June59AQI (US)
Lowest AQI (US) recorded in
December25AQI (US)
202236AQI (US)
26
4
21
30
1
17
27
4
25
5
19
4
2
28
1
27
4
26
4
23
8
271
35
Highest AQI (US) recorded in
June44AQI (US)
Lowest AQI (US) recorded in
September32AQI (US)
202138AQI (US)
27
2
17
5
24
4
27
3
29
2
23
5
16
15
24
7
21
4
29
2
17
3
27
4
281
56
Highest AQI (US) recorded in
July50AQI (US)
Lowest AQI (US) recorded in
October30AQI (US)
202040AQI (US)
10
3
17
3
18
24
4
2
27
4
30
1
27
2
27
2
1
25
3
21
8
226
30
3
Highest AQI (US) recorded in
June48AQI (US)
Lowest AQI (US) recorded in
May32AQI (US)
Most & Least Polluted Years Over the Last 7 Years
Most Polluted Year Recorded
2020(Avg.)
40AQI (US)Least Polluted Year Recorded
2024(Avg.)
31AQI (US)Chester's annual 2026 AQI (US) (32) shows an average percentage change of -12.1% (improved AQI (US)) compared to previous years: 2020 (40), 2021 (38), 2022 (36), 2023 (38), 2024 (31), 2025 (37).
