Decatur, 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
Decatur, Illinois, United States
2022
2023
2024
2025
2026
AQI
.
Days
AQI Trends: Highest and Lowest
Highest AQI recorded on
1st Aug 2025
112AQILowest AQI recorded on
21st Aug 2025
20AQISame Day Analysis (5th August):
On this day, AQI across the 5 years varied significantly: 2026 ranks 3rd highest AQI at 45 of Good air quality, showing improvement over 2025 and 2024 on the same day.
Day & Night AQI Trend: 4th Aug - 5th Aug 2026
Decatur, Illinois, United States
AQI
Day
Night
.
5 AM4th Aug 2026
8 PM
4 AM5th Aug 2026
Day time
Avg. Highest Time
7PM4th Aug
53AQI
Avg. Lowest Time
11AM4th Aug
40AQI
Night time
Avg. Highest Time
9PM4th Aug
54AQI
Avg. Lowest Time
4AM5th Aug
46AQI
In the last 24 hours,
Decatur's AQI reached its highest point of 54 at 9 PM during the Night, while the lowest point, 40, was recorded at 11 AM during the Day between 4th Aug and 5th Aug 2026.
Day & Night AQI Trend : Jul - Aug 2026
Decatur, Illinois, United States
JulAug
07th - 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 - 03rd03rd - 04th04th - 05th05th
Day
Night
7th Jul 2026305 AMAQI
7th Jul 2026306 AMAQI
7th Jul 2026307 AMAQI
7th Jul 2026308 AMAQI
7th Jul 2026309 AMAQI
7th Jul 20263210 AMAQI
7th Jul 20263211 AMAQI
7th Jul 20263012 PMAQI
7th Jul 2026301 PMAQI
7th Jul 2026302 PMAQI
7th Jul 2026303 PMAQI
7th Jul 2026304 PMAQI
7th Jul 2026325 PMAQI
7th Jul 2026306 PMAQI
7th Jul 2026287 PMAQI
7th Jul 2026298 PMAQI
7th Jul 2026299 PMAQI
7th Jul 20263610 PMAQI
7th Jul 20263811 PMAQI
8th Jul 20265012 AMAQI
8th Jul 2026501 AMAQI
8th Jul 2026402 AMAQI
8th Jul 2026303 AMAQI
8th Jul 2026294 AMAQI
25°C19/31°C
8th Jul 2026335 AMAQI
8th Jul 2026426 AMAQI
8th Jul 2026337 AMAQI
8th Jul 2026298 AMAQI
8th Jul 2026289 AMAQI
8th Jul 20264010 AMAQI
8th Jul 20263011 AMAQI
8th Jul 20263012 PMAQI
8th Jul 2026301 PMAQI
8th Jul 2026362 PMAQI
8th Jul 2026313 PMAQI
8th Jul 2026324 PMAQI
8th Jul 2026305 PMAQI
8th Jul 2026286 PMAQI
8th Jul 2026337 PMAQI
8th Jul 2026338 PMAQI
8th Jul 2026339 PMAQI
8th Jul 20263310 PMAQI
8th Jul 20263311 PMAQI
9th Jul 20265012 AMAQI
9th Jul 2026601 AMAQI
9th Jul 2026402 AMAQI
9th Jul 2026263 AMAQI
9th Jul 2026404 AMAQI
26°C19/33°C
9th Jul 2026385 AMAQI
9th Jul 2026406 AMAQI
9th Jul 2026327 AMAQI
9th Jul 2026288 AMAQI
9th Jul 2026369 AMAQI
9th Jul 20263210 AMAQI
9th Jul 20263211 AMAQI
9th Jul 20263612 PMAQI
9th Jul 2026321 PMAQI
9th Jul 2026302 PMAQI
9th Jul 2026343 PMAQI
9th Jul 2026424 PMAQI
9th Jul 2026385 PMAQI
9th Jul 2026386 PMAQI
9th Jul 2026307 PMAQI
9th Jul 2026348 PMAQI
9th Jul 2026409 PMAQI
9th Jul 20263310 PMAQI
9th Jul 20263211 PMAQI
10th Jul 20262812 AMAQI
10th Jul 2026281 AMAQI
10th Jul 2026312 AMAQI
10th Jul 2026323 AMAQI
10th Jul 2026324 AMAQI
26°C21/34°C
10th Jul 2026305 AMAQI
10th Jul 2026326 AMAQI
10th Jul 2026347 AMAQI
10th Jul 2026388 AMAQI
10th Jul 2026349 AMAQI
10th Jul 20264010 AMAQI
10th Jul 20264211 AMAQI
10th Jul 20263812 PMAQI
10th Jul 2026321 PMAQI
10th Jul 2026362 PMAQI
10th Jul 2026363 PMAQI
10th Jul 2026364 PMAQI
10th Jul 2026365 PMAQI
10th Jul 2026356 PMAQI
10th Jul 2026367 PMAQI
10th Jul 2026368 PMAQI
10th Jul 2026349 PMAQI
10th Jul 20263010 PMAQI
10th Jul 20262811 PMAQI
11th Jul 20262812 AMAQI
11th Jul 2026261 AMAQI
11th Jul 2026282 AMAQI
11th Jul 2026323 AMAQI
11th Jul 2026304 AMAQI
26°C20/34°C
11th Jul 2026305 AMAQI
11th Jul 2026286 AMAQI
11th Jul 2026327 AMAQI
11th Jul 2026328 AMAQI
11th Jul 2026329 AMAQI
11th Jul 20263410 AMAQI
11th Jul 20263211 AMAQI
11th Jul 20263412 PMAQI
11th Jul 2026321 PMAQI
11th Jul 2026282 PMAQI
11th Jul 2026303 PMAQI
11th Jul 2026334 PMAQI
11th Jul 2026325 PMAQI
11th Jul 2026346 PMAQI
11th Jul 2026327 PMAQI
11th Jul 2026328 PMAQI
11th Jul 2026269 PMAQI
11th Jul 20262810 PMAQI
11th Jul 20262411 PMAQI
12th Jul 20262412 AMAQI
12th Jul 2026311 AMAQI
12th Jul 2026262 AMAQI
12th Jul 2026323 AMAQI
12th Jul 2026314 AMAQI
24°C22/28°C
12th Jul 2026305 AMAQI
12th Jul 2026286 AMAQI
12th Jul 2026327 AMAQI
12th Jul 2026318 AMAQI
12th Jul 2026319 AMAQI
12th Jul 20263010 AMAQI
12th Jul 20263011 AMAQI
12th Jul 20262912 PMAQI
12th Jul 2026301 PMAQI
12th Jul 2026282 PMAQI
12th Jul 2026283 PMAQI
12th Jul 2026304 PMAQI
12th Jul 2026285 PMAQI
12th Jul 2026326 PMAQI
12th Jul 2026317 PMAQI
12th Jul 2026288 PMAQI
12th Jul 2026309 PMAQI
12th Jul 20263010 PMAQI
12th Jul 20263111 PMAQI
13th Jul 20262812 AMAQI
13th Jul 2026271 AMAQI
13th Jul 2026262 AMAQI
13th Jul 2026323 AMAQI
13th Jul 2026324 AMAQI
25°C19/32°C
13th Jul 2026325 AMAQI
13th Jul 2026306 AMAQI
13th Jul 2026327 AMAQI
13th Jul 2026348 AMAQI
13th Jul 2026349 AMAQI
13th Jul 20263610 AMAQI
13th Jul 20263611 AMAQI
13th Jul 20263612 PMAQI
13th Jul 2026331 PMAQI
13th Jul 2026282 PMAQI
13th Jul 2026343 PMAQI
13th Jul 2026324 PMAQI
13th Jul 2026305 PMAQI
13th Jul 2026286 PMAQI
13th Jul 2026327 PMAQI
13th Jul 2026328 PMAQI
13th Jul 2026309 PMAQI
13th Jul 20262710 PMAQI
13th Jul 20264211 PMAQI
14th Jul 20264212 AMAQI
14th Jul 2026261 AMAQI
14th Jul 2026282 AMAQI
14th Jul 2026343 AMAQI
14th Jul 2026344 AMAQI
25°C17/32°C
14th Jul 2026325 AMAQI
14th Jul 2026346 AMAQI
14th Jul 2026347 AMAQI
14th Jul 2026328 AMAQI
14th Jul 2026349 AMAQI
14th Jul 20263710 AMAQI
14th Jul 20263211 AMAQI
14th Jul 20263612 PMAQI
14th Jul 2026341 PMAQI
14th Jul 2026302 PMAQI
14th Jul 2026323 PMAQI
14th Jul 2026264 PMAQI
14th Jul 2026325 PMAQI
14th Jul 2026326 PMAQI
14th Jul 2026307 PMAQI
14th Jul 2026328 PMAQI
14th Jul 2026269 PMAQI
14th Jul 20262410 PMAQI
14th Jul 20262211 PMAQI
15th Jul 20262212 AMAQI
15th Jul 2026401 AMAQI
15th Jul 2026282 AMAQI
15th Jul 2026273 AMAQI
15th Jul 2026284 AMAQI
26°C19/34°C
15th Jul 2026285 AMAQI
15th Jul 2026336 AMAQI
15th Jul 2026287 AMAQI
15th Jul 2026288 AMAQI
15th Jul 2026269 AMAQI
15th Jul 20265010 AMAQI
15th Jul 20262811 AMAQI
15th Jul 20264012 PMAQI
15th Jul 2026361 PMAQI
15th Jul 2026292 PMAQI
15th Jul 2026323 PMAQI
15th Jul 2026344 PMAQI
15th Jul 2026325 PMAQI
15th Jul 2026306 PMAQI
15th Jul 2026307 PMAQI
15th Jul 2026328 PMAQI
15th Jul 2026289 PMAQI
15th Jul 20262810 PMAQI
15th Jul 20263611 PMAQI
16th Jul 20262612 AMAQI
16th Jul 2026241 AMAQI
16th Jul 2026242 AMAQI
16th Jul 2026283 AMAQI
16th Jul 2026284 AMAQI
27°C20/35°C
16th Jul 2026365 AMAQI
16th Jul 2026306 AMAQI
16th Jul 2026307 AMAQI
16th Jul 2026288 AMAQI
16th Jul 2026309 AMAQI
16th Jul 20263210 AMAQI
16th Jul 20263211 AMAQI
16th Jul 20263012 PMAQI
16th Jul 2026311 PMAQI
16th Jul 2026302 PMAQI
16th Jul 2026303 PMAQI
16th Jul 2026304 PMAQI
16th Jul 2026305 PMAQI
16th Jul 2026286 PMAQI
16th Jul 2026267 PMAQI
16th Jul 2026318 PMAQI
16th Jul 2026289 PMAQI
16th Jul 20262610 PMAQI
16th Jul 20262611 PMAQI
17th Jul 20262412 AMAQI
17th Jul 2026241 AMAQI
17th Jul 2026312 AMAQI
17th Jul 2026313 AMAQI
17th Jul 2026404 AMAQI
28°C20/35°C
17th Jul 2026705 AMAQI
17th Jul 2026696 AMAQI
17th Jul 2026557 AMAQI
17th Jul 2026728 AMAQI
17th Jul 2026409 AMAQI
17th Jul 20264010 AMAQI
17th Jul 20264211 AMAQI
17th Jul 20264812 PMAQI
17th Jul 2026441 PMAQI
17th Jul 2026462 PMAQI
17th Jul 2026513 PMAQI
17th Jul 2026554 PMAQI
17th Jul 2026525 PMAQI
17th Jul 2026466 PMAQI
17th Jul 2026467 PMAQI
17th Jul 2026448 PMAQI
17th Jul 2026529 PMAQI
17th Jul 20264910 PMAQI
17th Jul 20265111 PMAQI
18th Jul 20263812 AMAQI
18th Jul 2026421 AMAQI
18th Jul 2026442 AMAQI
18th Jul 2026403 AMAQI
18th Jul 2026384 AMAQI
28°C23/33°C
18th Jul 2026405 AMAQI
18th Jul 2026406 AMAQI
18th Jul 2026407 AMAQI
18th Jul 2026428 AMAQI
18th Jul 2026449 AMAQI
18th Jul 20264410 AMAQI
18th Jul 20265011 AMAQI
18th Jul 20264612 PMAQI
18th Jul 2026461 PMAQI
18th Jul 2026502 PMAQI
18th Jul 2026443 PMAQI
18th Jul 2026444 PMAQI
18th Jul 2026445 PMAQI
18th Jul 2026466 PMAQI
18th Jul 2026487 PMAQI
18th Jul 2026518 PMAQI
18th Jul 2026509 PMAQI
18th Jul 20265110 PMAQI
18th Jul 20265411 PMAQI
19th Jul 20265812 AMAQI
19th Jul 2026591 AMAQI
19th Jul 2026582 AMAQI
19th Jul 2026573 AMAQI
19th Jul 2026624 AMAQI
28°C23/34°C
19th Jul 2026705 AMAQI
19th Jul 2026726 AMAQI
19th Jul 2026757 AMAQI
19th Jul 2026748 AMAQI
19th Jul 2026749 AMAQI
19th Jul 20267210 AMAQI
19th Jul 20268011 AMAQI
19th Jul 20267812 PMAQI
19th Jul 2026821 PMAQI
19th Jul 2026732 PMAQI
19th Jul 2026743 PMAQI
19th Jul 2026814 PMAQI
19th Jul 2026765 PMAQI
19th Jul 2026746 PMAQI
19th Jul 2026847 PMAQI
19th Jul 2026788 PMAQI
19th Jul 2026769 PMAQI
19th Jul 20267210 PMAQI
19th Jul 20266311 PMAQI
20th Jul 20267212 AMAQI
20th Jul 2026741 AMAQI
20th Jul 2026732 AMAQI
20th Jul 2026803 AMAQI
20th Jul 2026724 AMAQI
25°C22/32°C
20th Jul 2026745 AMAQI
20th Jul 2026786 AMAQI
20th Jul 2026797 AMAQI
20th Jul 2026928 AMAQI
20th Jul 2026869 AMAQI
20th Jul 20268310 AMAQI
20th Jul 20267711 AMAQI
20th Jul 20267012 PMAQI
20th Jul 2026631 PMAQI
20th Jul 2026712 PMAQI
20th Jul 2026743 PMAQI
20th Jul 2026724 PMAQI
20th Jul 2026745 PMAQI
20th Jul 2026786 PMAQI
20th Jul 2026817 PMAQI
20th Jul 2026818 PMAQI
20th Jul 2026729 PMAQI
20th Jul 20265911 PMAQI
21st Jul 20267112 AMAQI
21st Jul 2026661 AMAQI
21st Jul 2026622 AMAQI
21st Jul 2026613 AMAQI
21st Jul 2026664 AMAQI
25°C18/32°C
21st Jul 2026655 AMAQI
21st Jul 2026666 AMAQI
21st Jul 2026587 AMAQI
21st Jul 2026528 AMAQI
21st Jul 2026519 AMAQI
21st Jul 20265310 AMAQI
21st Jul 20265011 AMAQI
21st Jul 20264612 PMAQI
21st Jul 2026501 PMAQI
21st Jul 2026542 PMAQI
21st Jul 2026563 PMAQI
21st Jul 2026604 PMAQI
21st Jul 2026585 PMAQI
21st Jul 2026606 PMAQI
21st Jul 2026557 PMAQI
21st Jul 2026558 PMAQI
21st Jul 2026549 PMAQI
21st Jul 20264810 PMAQI
21st Jul 20264611 PMAQI
22nd Jul 20264412 AMAQI
22nd Jul 2026421 AMAQI
22nd Jul 2026382 AMAQI
22nd Jul 2026443 AMAQI
22nd Jul 2026484 AMAQI
27°C22/34°C
22nd Jul 2026485 AMAQI
22nd Jul 2026486 AMAQI
22nd Jul 2026487 AMAQI
22nd Jul 2026448 AMAQI
22nd Jul 2026529 AMAQI
22nd Jul 20264810 AMAQI
22nd Jul 20264211 AMAQI
22nd Jul 20264012 PMAQI
22nd Jul 2026501 PMAQI
22nd Jul 2026362 PMAQI
22nd Jul 2026503 PMAQI
22nd Jul 2026384 PMAQI
22nd Jul 2026405 PMAQI
22nd Jul 2026426 PMAQI
22nd Jul 2026387 PMAQI
22nd Jul 2026348 PMAQI
22nd Jul 2026689 PMAQI
22nd Jul 20264610 PMAQI
22nd Jul 20263411 PMAQI
23rd Jul 20263812 AMAQI
23rd Jul 2026381 AMAQI
23rd Jul 2026382 AMAQI
23rd Jul 2026383 AMAQI
23rd Jul 2026344 AMAQI
21°C17/27°C
23rd Jul 2026345 AMAQI
23rd Jul 2026426 AMAQI
23rd Jul 2026307 AMAQI
23rd Jul 2026338 AMAQI
23rd Jul 2026299 AMAQI
23rd Jul 20264610 AMAQI
23rd Jul 20264611 AMAQI
23rd Jul 20263812 PMAQI
23rd Jul 2026531 PMAQI
23rd Jul 2026322 PMAQI
23rd Jul 2026423 PMAQI
23rd Jul 2026294 PMAQI
23rd Jul 2026385 PMAQI
23rd Jul 2026256 PMAQI
23rd Jul 2026427 PMAQI
23rd Jul 2026368 PMAQI
23rd Jul 2026269 PMAQI
23rd Jul 20262210 PMAQI
23rd Jul 20263011 PMAQI
24th Jul 20264612 AMAQI
24th Jul 2026501 AMAQI
24th Jul 2026362 AMAQI
24th Jul 2026403 AMAQI
24th Jul 2026524 AMAQI
20°C12/27°C
24th Jul 2026525 AMAQI
24th Jul 2026386 AMAQI
24th Jul 2026407 AMAQI
24th Jul 2026428 AMAQI
24th Jul 2026409 AMAQI
24th Jul 20264010 AMAQI
24th Jul 20265011 AMAQI
24th Jul 20263812 PMAQI
24th Jul 2026461 PMAQI
24th Jul 2026422 PMAQI
24th Jul 2026313 PMAQI
24th Jul 2026384 PMAQI
24th Jul 2026275 PMAQI
24th Jul 2026426 PMAQI
24th Jul 2026267 PMAQI
24th Jul 2026238 PMAQI
24th Jul 2026429 PMAQI
24th Jul 20262910 PMAQI
24th Jul 20263211 PMAQI
25th Jul 20264212 AMAQI
25th Jul 2026541 AMAQI
25th Jul 2026422 AMAQI
25th Jul 2026443 AMAQI
25th Jul 2026504 AMAQI
21°C13/29°C
25th Jul 2026505 AMAQI
25th Jul 2026326 AMAQI
25th Jul 2026507 AMAQI
25th Jul 2026558 AMAQI
25th Jul 2026549 AMAQI
25th Jul 20265010 AMAQI
25th Jul 20263811 AMAQI
25th Jul 20264212 PMAQI
25th Jul 2026441 PMAQI
25th Jul 2026502 PMAQI
25th Jul 2026553 PMAQI
25th Jul 2026534 PMAQI
25th Jul 2026505 PMAQI
25th Jul 2026506 PMAQI
25th Jul 2026527 PMAQI
25th Jul 2026518 PMAQI
25th Jul 2026529 PMAQI
25th Jul 20264410 PMAQI
25th Jul 20265111 PMAQI
26th Jul 20264812 AMAQI
26th Jul 2026501 AMAQI
26th Jul 2026512 AMAQI
26th Jul 2026483 AMAQI
26th Jul 2026484 AMAQI
22°C19/27°C
26th Jul 2026525 AMAQI
26th Jul 2026496 AMAQI
26th Jul 2026507 AMAQI
26th Jul 2026428 AMAQI
26th Jul 2026389 AMAQI
26th Jul 20264810 AMAQI
26th Jul 20265111 AMAQI
26th Jul 20265612 PMAQI
26th Jul 2026571 PMAQI
26th Jul 2026602 PMAQI
26th Jul 2026593 PMAQI
26th Jul 2026594 PMAQI
26th Jul 2026565 PMAQI
26th Jul 2026616 PMAQI
26th Jul 2026637 PMAQI
26th Jul 2026668 PMAQI
26th Jul 2026669 PMAQI
26th Jul 20266710 PMAQI
26th Jul 20266411 PMAQI
27th Jul 20265712 AMAQI
27th Jul 2026641 AMAQI
27th Jul 2026662 AMAQI
27th Jul 2026623 AMAQI
27th Jul 2026664 AMAQI
27°C22/37°C
27th Jul 2026645 AMAQI
27th Jul 2026606 AMAQI
27th Jul 2026547 AMAQI
27th Jul 2026448 AMAQI
27th Jul 2026429 AMAQI
27th Jul 20264210 AMAQI
27th Jul 20264211 AMAQI
27th Jul 20264212 PMAQI
27th Jul 2026441 PMAQI
27th Jul 2026522 PMAQI
27th Jul 2026563 PMAQI
27th Jul 2026594 PMAQI
27th Jul 2026595 PMAQI
27th Jul 2026636 PMAQI
27th Jul 2026597 PMAQI
27th Jul 2026598 PMAQI
27th Jul 2026589 PMAQI
27th Jul 20266010 PMAQI
27th Jul 20266011 PMAQI
28th Jul 20265612 AMAQI
28th Jul 2026541 AMAQI
28th Jul 2026552 AMAQI
28th Jul 2026533 AMAQI
28th Jul 2026534 AMAQI
29°C24/37°C
28th Jul 2026525 AMAQI
28th Jul 2026536 AMAQI
28th Jul 2026537 AMAQI
28th Jul 2026538 AMAQI
28th Jul 2026549 AMAQI
28th Jul 20265810 AMAQI
28th Jul 20265511 AMAQI
28th Jul 20265412 PMAQI
28th Jul 2026531 PMAQI
28th Jul 2026542 PMAQI
28th Jul 2026553 PMAQI
28th Jul 2026464 PMAQI
28th Jul 2026445 PMAQI
28th Jul 2026426 PMAQI
28th Jul 2026467 PMAQI
28th Jul 2026518 PMAQI
28th Jul 2026489 PMAQI
28th Jul 20265010 PMAQI
28th Jul 20265211 PMAQI
29th Jul 20265512 AMAQI
29th Jul 2026541 AMAQI
29th Jul 2026502 AMAQI
29th Jul 2026533 AMAQI
29th Jul 2026524 AMAQI
27°C21/33°C
29th Jul 2026505 AMAQI
29th Jul 2026486 AMAQI
29th Jul 2026547 AMAQI
29th Jul 2026518 AMAQI
29th Jul 2026469 AMAQI
29th Jul 20264210 AMAQI
29th Jul 20264411 AMAQI
29th Jul 20262512 PMAQI
29th Jul 2026401 PMAQI
29th Jul 2026502 PMAQI
29th Jul 2026363 PMAQI
29th Jul 2026384 PMAQI
29th Jul 2026365 PMAQI
29th Jul 2026406 PMAQI
29th Jul 2026257 PMAQI
29th Jul 2026218 PMAQI
29th Jul 2026529 PMAQI
29th Jul 20264210 PMAQI
29th Jul 20263411 PMAQI
30th Jul 20264612 AMAQI
30th Jul 2026311 AMAQI
30th Jul 2026292 AMAQI
30th Jul 2026443 AMAQI
30th Jul 2026504 AMAQI
23°C15/32°C
30th Jul 2026445 AMAQI
30th Jul 2026366 AMAQI
30th Jul 2026447 AMAQI
30th Jul 2026468 AMAQI
30th Jul 2026469 AMAQI
30th Jul 20264410 AMAQI
30th Jul 20264611 AMAQI
30th Jul 20263812 PMAQI
30th Jul 2026421 PMAQI
30th Jul 2026422 PMAQI
30th Jul 2026423 PMAQI
30th Jul 2026464 PMAQI
30th Jul 2026425 PMAQI
30th Jul 2026446 PMAQI
30th Jul 2026447 PMAQI
30th Jul 2026428 PMAQI
30th Jul 2026449 PMAQI
30th Jul 20264610 PMAQI
30th Jul 20264011 PMAQI
31st Jul 20264012 AMAQI
31st Jul 2026461 AMAQI
31st Jul 2026402 AMAQI
31st Jul 2026363 AMAQI
31st Jul 2026424 AMAQI
23°C15/31°C
31st Jul 2026425 AMAQI
31st Jul 2026426 AMAQI
31st Jul 2026427 AMAQI
31st Jul 2026468 AMAQI
31st Jul 2026489 AMAQI
31st Jul 20264410 AMAQI
31st Jul 20264411 AMAQI
31st Jul 20264212 PMAQI
31st Jul 2026421 PMAQI
31st Jul 2026212 PMAQI
31st Jul 2026383 PMAQI
31st Jul 2026444 PMAQI
31st Jul 2026445 PMAQI
31st Jul 2026406 PMAQI
31st Jul 2026447 PMAQI
31st Jul 2026448 PMAQI
31st Jul 2026509 PMAQI
31st Jul 20264810 PMAQI
31st Jul 20264811 PMAQI
1st Aug 20264612 AMAQI
1st Aug 2026481 AMAQI
1st Aug 2026462 AMAQI
1st Aug 2026443 AMAQI
1st Aug 2026424 AMAQI
22°C18/30°C
1st Aug 2026445 AMAQI
1st Aug 2026466 AMAQI
1st Aug 2026327 AMAQI
1st Aug 2026388 AMAQI
1st Aug 2026329 AMAQI
1st Aug 20263410 AMAQI
1st Aug 20264211 AMAQI
1st Aug 20264212 PMAQI
1st Aug 2026461 PMAQI
1st Aug 2026462 PMAQI
1st Aug 2026383 PMAQI
1st Aug 2026494 PMAQI
1st Aug 2026465 PMAQI
1st Aug 2026386 PMAQI
1st Aug 2026367 PMAQI
1st Aug 2026518 PMAQI
1st Aug 2026319 PMAQI
1st Aug 20263810 PMAQI
1st Aug 20263811 PMAQI
2nd Aug 20264412 AMAQI
2nd Aug 2026401 AMAQI
2nd Aug 2026442 AMAQI
2nd Aug 2026403 AMAQI
2nd Aug 2026424 AMAQI
21°C20/22°C
2nd Aug 2026465 AMAQI
2nd Aug 2026426 AMAQI
2nd Aug 2026447 AMAQI
2nd Aug 2026468 AMAQI
2nd Aug 2026489 AMAQI
2nd Aug 20265210 AMAQI
2nd Aug 20265111 AMAQI
2nd Aug 20264912 PMAQI
2nd Aug 2026481 PMAQI
2nd Aug 2026502 PMAQI
2nd Aug 2026513 PMAQI
2nd Aug 2026514 PMAQI
2nd Aug 2026505 PMAQI
2nd Aug 2026486 PMAQI
2nd Aug 2026507 PMAQI
2nd Aug 2026518 PMAQI
2nd Aug 2026469 PMAQI
2nd Aug 20265010 PMAQI
2nd Aug 20264911 PMAQI
3rd Aug 20264812 AMAQI
3rd Aug 2026511 AMAQI
3rd Aug 2026482 AMAQI
3rd Aug 2026503 AMAQI
3rd Aug 2026504 AMAQI
23°C19/28°C
3rd Aug 2026485 AMAQI
3rd Aug 2026446 AMAQI
3rd Aug 2026427 AMAQI
3rd Aug 2026408 AMAQI
3rd Aug 2026389 AMAQI
3rd Aug 20263810 AMAQI
3rd Aug 20264211 AMAQI
3rd Aug 20265012 PMAQI
3rd Aug 2026441 PMAQI
3rd Aug 2026382 PMAQI
3rd Aug 2026483 PMAQI
3rd Aug 2026384 PMAQI
3rd Aug 2026445 PMAQI
3rd Aug 2026426 PMAQI
3rd Aug 2026467 PMAQI
3rd Aug 2026448 PMAQI
3rd Aug 2026449 PMAQI
3rd Aug 20264810 PMAQI
3rd Aug 20265011 PMAQI
4th Aug 20265212 AMAQI
4th Aug 2026531 AMAQI
4th Aug 2026402 AMAQI
4th Aug 2026423 AMAQI
4th Aug 2026384 AMAQI
23°C16/31°C
4th Aug 2026425 AMAQI
4th Aug 2026426 AMAQI
4th Aug 2026427 AMAQI
4th Aug 2026408 AMAQI
4th Aug 2026409 AMAQI
4th Aug 20264410 AMAQI
4th Aug 20264011 AMAQI
4th Aug 20264412 PMAQI
4th Aug 2026421 PMAQI
4th Aug 2026442 PMAQI
4th Aug 2026443 PMAQI
4th Aug 2026484 PMAQI
4th Aug 2026505 PMAQI
4th Aug 2026516 PMAQI
4th Aug 2026537 PMAQI
4th Aug 2026518 PMAQI
4th Aug 2026549 PMAQI
4th Aug 20265410 PMAQI
4th Aug 20265211 PMAQI
5th Aug 20265112 AMAQI
5th Aug 2026501 AMAQI
5th Aug 2026462 AMAQI
5th Aug 2026463 AMAQI
5th Aug 2026464 AMAQI
24°C17/32°C
5th Aug 2026485 AMAQI
5 AM5th Aug 2026426 AMAQI
5th Aug 2026427 AMAQI
5th Aug 2026428 AMAQI
5th Aug 2026429 AMAQI
5th Aug 20264410 AMAQI
5th Aug 20264211 AMAQI
5th Aug 20264412 PMAQI
12 PM5th Aug 2026421 PMAQI
5th Aug 2026422 PMAQI
5th Aug 2026483 PMAQI
5th Aug 2026444 PMAQI
5th Aug 2026505 PMAQI
5th Aug 2026446 PMAQI
5th Aug 2026467 PMAQI
5th Aug 2026448 PMAQI
8 PM5th Aug 2026449 PMAQI
5th Aug 20264210 PMAQI
5th Aug 20264611 PMAQI
12 AM
4 AM
25°C18/33°C
Day time
Avg. Highest Time
5 AM - 8 PM
43AQI
16 hours / Day
480 hours / Month
Avg. Lowest Time
5 AM - 9 AM
43AQI
5 hours / Day
150 hours / Month
In the last 30 days, during the daytime, the highest AQI was between 5 AM to 8 PM (Avg. 43), while the lowest AQI was between 5 AM to 9 AM (Avg. 43).
Night time
Avg. Highest Time
12 AM - 1 AM
44AQI
2 hours / Day
60 hours / Month
Avg. Lowest Time
10 PM - 11 PM
42AQI
2 hours / Day
60 hours / Month
In the last 30 days, during the daytime, the highest AQI was between 12 AM to 1 AM (Avg. 44), while the lowest AQI was between 10 PM to 11 PM (Avg. 42).
2026 Days Vs Air Quality
Decatur, Illinois, United States
2026
92%
196
8%
18
Total number of days with different AQI categories in last 217 days in 2026 (148 days remaining)
Good
196 DaysModerate
18 DaysPoor
0 DaysUnhealthy
0 DaysSevere
0 DaysHazardous
0 DaysUnder WHO’s Safe Air Quality Limits: 92%
Health Risk Level:
Very Low
In 2026, 92% of 217 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
Decatur, 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
24AQI (US)
24AQI (US)
2nd January 2026
29AQI (US)
29AQI (US)
3rd January 2026
30AQI (US)
30AQI (US)
4th January 2026
43AQI (US)
43AQI (US)
5th January 2026
42AQI (US)
42AQI (US)
6th January 2026
46AQI (US)
46AQI (US)
7th January 2026
50AQI (US)
50AQI (US)
8th January 2026
40AQI (US)
40AQI (US)
9th January 2026
22AQI (US)
22AQI (US)
10th January 2026
23AQI (US)
23AQI (US)
11th January 2026
18AQI (US)
18AQI (US)
12th January 2026
28AQI (US)
28AQI (US)
13th January 2026
26AQI (US)
26AQI (US)
14th January 2026
12AQI (US)
12AQI (US)
15th January 2026
9AQI (US)
9AQI (US)
16th January 2026
19AQI (US)
19AQI (US)
17th January 2026
12AQI (US)
12AQI (US)
18th January 2026
14AQI (US)
14AQI (US)
19th January 2026
13AQI (US)
13AQI (US)
20th January 2026
17AQI (US)
17AQI (US)
21st January 2026
33AQI (US)
33AQI (US)
22nd January 2026
57AQI (US)
57AQI (US)
23rd January 2026
58AQI (US)
58AQI (US)
24th January 2026
50AQI (US)
50AQI (US)
25th January 2026
52AQI (US)
52AQI (US)
26th January 2026
49AQI (US)
49AQI (US)
27th January 2026
37AQI (US)
37AQI (US)
28th January 2026
44AQI (US)
44AQI (US)
29th January 2026
56AQI (US)
56AQI (US)
30th January 2026
64AQI (US)
64AQI (US)
31st January 2026
42AQI (US)
42AQI (US)
1st February 2026
46AQI (US)
46AQI (US)
2nd February 2026
51AQI (US)
51AQI (US)
3rd February 2026
48AQI (US)
48AQI (US)
4th February 2026
44AQI (US)
44AQI (US)
5th February 2026
49AQI (US)
49AQI (US)
6th February 2026
44AQI (US)
44AQI (US)
7th February 2026
40AQI (US)
40AQI (US)
8th February 2026
43AQI (US)
43AQI (US)
9th February 2026
47AQI (US)
47AQI (US)
10th February 2026
46AQI (US)
46AQI (US)
11th February 2026
39AQI (US)
39AQI (US)
12th February 2026
38AQI (US)
38AQI (US)
13th February 2026
50AQI (US)
50AQI (US)
14th February 2026
51AQI (US)
51AQI (US)
15th February 2026
47AQI (US)
47AQI (US)
16th February 2026
45AQI (US)
45AQI (US)
17th February 2026
50AQI (US)
50AQI (US)
18th February 2026
44AQI (US)
44AQI (US)
19th February 2026
43AQI (US)
43AQI (US)
20th February 2026
39AQI (US)
39AQI (US)
21st February 2026
37AQI (US)
37AQI (US)
22nd February 2026
36AQI (US)
36AQI (US)
23rd February 2026
39AQI (US)
39AQI (US)
24th February 2026
45AQI (US)
45AQI (US)
25th February 2026
44AQI (US)
44AQI (US)
26th February 2026
34AQI (US)
34AQI (US)
27th February 2026
34AQI (US)
34AQI (US)
28th February 2026
32AQI (US)
32AQI (US)
1st March 2026
38AQI (US)
38AQI (US)
2nd March 2026
55AQI (US)
55AQI (US)
3rd March 2026
44AQI (US)
44AQI (US)
4th March 2026
45AQI (US)
45AQI (US)
5th March 2026
40AQI (US)
40AQI (US)
6th March 2026
38AQI (US)
38AQI (US)
7th March 2026
36AQI (US)
36AQI (US)
8th March 2026
39AQI (US)
39AQI (US)
9th March 2026
36AQI (US)
36AQI (US)
10th March 2026
33AQI (US)
33AQI (US)
11th March 2026
40AQI (US)
40AQI (US)
12th March 2026
38AQI (US)
38AQI (US)
13th March 2026
40AQI (US)
40AQI (US)
14th March 2026
35AQI (US)
35AQI (US)
15th March 2026
32AQI (US)
32AQI (US)
16th March 2026
36AQI (US)
36AQI (US)
17th March 2026
34AQI (US)
34AQI (US)
18th March 2026
30AQI (US)
30AQI (US)
19th March 2026
41AQI (US)
41AQI (US)
20th March 2026
43AQI (US)
43AQI (US)
21st March 2026
36AQI (US)
36AQI (US)
22nd March 2026
33AQI (US)
33AQI (US)
23rd March 2026
40AQI (US)
40AQI (US)
24th March 2026
35AQI (US)
35AQI (US)
25th March 2026
32AQI (US)
32AQI (US)
26th March 2026
30AQI (US)
30AQI (US)
27th March 2026
30AQI (US)
30AQI (US)
28th March 2026
30AQI (US)
30AQI (US)
29th March 2026
30AQI (US)
30AQI (US)
30th March 2026
28AQI (US)
28AQI (US)
31st March 2026
26AQI (US)
26AQI (US)
1st April 2026
29AQI (US)
29AQI (US)
2nd April 2026
30AQI (US)
30AQI (US)
3rd April 2026
28AQI (US)
28AQI (US)
4th April 2026
30AQI (US)
30AQI (US)
5th April 2026
29AQI (US)
29AQI (US)
6th April 2026
30AQI (US)
30AQI (US)
7th April 2026
28AQI (US)
28AQI (US)
8th April 2026
38AQI (US)
38AQI (US)
9th April 2026
28AQI (US)
28AQI (US)
10th April 2026
33AQI (US)
33AQI (US)
11th April 2026
31AQI (US)
31AQI (US)
12th April 2026
31AQI (US)
31AQI (US)
13th April 2026
32AQI (US)
32AQI (US)
14th April 2026
32AQI (US)
32AQI (US)
15th April 2026
33AQI (US)
33AQI (US)
16th April 2026
29AQI (US)
29AQI (US)
17th April 2026
18th April 2026
30AQI (US)
30AQI (US)
19th April 2026
33AQI (US)
33AQI (US)
20th April 2026
28AQI (US)
28AQI (US)
21st April 2026
27AQI (US)
27AQI (US)
22nd April 2026
23rd April 2026
25AQI (US)
25AQI (US)
24th April 2026
26AQI (US)
26AQI (US)
25th April 2026
28AQI (US)
28AQI (US)
26th April 2026
34AQI (US)
34AQI (US)
27th April 2026
27AQI (US)
27AQI (US)
28th April 2026
25AQI (US)
25AQI (US)
29th April 2026
25AQI (US)
25AQI (US)
30th April 2026
28AQI (US)
28AQI (US)
1st May 2026
26AQI (US)
26AQI (US)
2nd May 2026
25AQI (US)
25AQI (US)
3rd May 2026
22AQI (US)
22AQI (US)
4th May 2026
36AQI (US)
36AQI (US)
5th May 2026
38AQI (US)
38AQI (US)
6th May 2026
30AQI (US)
30AQI (US)
7th May 2026
28AQI (US)
28AQI (US)
8th May 2026
35AQI (US)
35AQI (US)
9th May 2026
10th May 2026
31AQI (US)
31AQI (US)
11th May 2026
28AQI (US)
28AQI (US)
12th May 2026
32AQI (US)
32AQI (US)
13th May 2026
28AQI (US)
28AQI (US)
14th May 2026
26AQI (US)
26AQI (US)
15th May 2026
47AQI (US)
47AQI (US)
16th May 2026
51AQI (US)
51AQI (US)
17th May 2026
56AQI (US)
56AQI (US)
18th May 2026
57AQI (US)
57AQI (US)
19th May 2026
55AQI (US)
55AQI (US)
20th May 2026
50AQI (US)
50AQI (US)
21st May 2026
43AQI (US)
43AQI (US)
22nd May 2026
44AQI (US)
44AQI (US)
23rd May 2026
50AQI (US)
50AQI (US)
24th May 2026
46AQI (US)
46AQI (US)
25th May 2026
44AQI (US)
44AQI (US)
26th May 2026
28AQI (US)
28AQI (US)
27th May 2026
28AQI (US)
28AQI (US)
28th May 2026
25AQI (US)
25AQI (US)
29th May 2026
26AQI (US)
26AQI (US)
30th May 2026
28AQI (US)
28AQI (US)
31st May 2026
29AQI (US)
29AQI (US)
1st June 2026
31AQI (US)
31AQI (US)
2nd June 2026
31AQI (US)
31AQI (US)
3rd June 2026
30AQI (US)
30AQI (US)
4th June 2026
27AQI (US)
27AQI (US)
5th June 2026
27AQI (US)
27AQI (US)
6th June 2026
25AQI (US)
25AQI (US)
7th June 2026
26AQI (US)
26AQI (US)
8th June 2026
26AQI (US)
26AQI (US)
9th June 2026
26AQI (US)
26AQI (US)
10th June 2026
27AQI (US)
27AQI (US)
11th June 2026
27AQI (US)
27AQI (US)
12th June 2026
26AQI (US)
26AQI (US)
13th June 2026
26AQI (US)
26AQI (US)
14th June 2026
24AQI (US)
24AQI (US)
15th June 2026
26AQI (US)
26AQI (US)
16th June 2026
27AQI (US)
27AQI (US)
17th June 2026
28AQI (US)
28AQI (US)
18th June 2026
29AQI (US)
29AQI (US)
19th June 2026
27AQI (US)
27AQI (US)
20th June 2026
24AQI (US)
24AQI (US)
21st June 2026
26AQI (US)
26AQI (US)
22nd June 2026
24AQI (US)
24AQI (US)
23rd June 2026
24AQI (US)
24AQI (US)
24th June 2026
25AQI (US)
25AQI (US)
25th June 2026
25AQI (US)
25AQI (US)
26th June 2026
27AQI (US)
27AQI (US)
27th June 2026
29AQI (US)
29AQI (US)
28th June 2026
30AQI (US)
30AQI (US)
29th June 2026
29AQI (US)
29AQI (US)
30th June 2026
38AQI (US)
38AQI (US)
1st July 2026
28AQI (US)
28AQI (US)
2nd July 2026
33AQI (US)
33AQI (US)
3rd July 2026
29AQI (US)
29AQI (US)
4th July 2026
28AQI (US)
28AQI (US)
5th July 2026
30AQI (US)
30AQI (US)
6th July 2026
30AQI (US)
30AQI (US)
7th July 2026
32AQI (US)
32AQI (US)
8th July 2026
34AQI (US)
34AQI (US)
9th July 2026
36AQI (US)
36AQI (US)
10th July 2026
34AQI (US)
34AQI (US)
11th July 2026
30AQI (US)
30AQI (US)
12th July 2026
30AQI (US)
30AQI (US)
13th July 2026
32AQI (US)
32AQI (US)
14th July 2026
32AQI (US)
32AQI (US)
15th July 2026
31AQI (US)
31AQI (US)
16th July 2026
29AQI (US)
29AQI (US)
17th July 2026
47AQI (US)
47AQI (US)
18th July 2026
45AQI (US)
45AQI (US)
19th July 2026
72AQI (US)
72AQI (US)
20th July 2026
76AQI (US)
76AQI (US)
21st July 2026
57AQI (US)
57AQI (US)
22nd July 2026
44AQI (US)
44AQI (US)
23rd July 2026
36AQI (US)
36AQI (US)
24th July 2026
39AQI (US)
39AQI (US)
25th July 2026
48AQI (US)
48AQI (US)
26th July 2026
54AQI (US)
54AQI (US)
27th July 2026
56AQI (US)
56AQI (US)
28th July 2026
52AQI (US)
52AQI (US)
29th July 2026
43AQI (US)
43AQI (US)
30th July 2026
42AQI (US)
42AQI (US)
31st July 2026
42AQI (US)
42AQI (US)
1st August 2026
41AQI (US)
41AQI (US)
2nd August 2026
47AQI (US)
47AQI (US)
3rd August 2026
45AQI (US)
45AQI (US)
4th August 2026
46AQI (US)
46AQI (US)
5th August 2026
45AQI (US)
45AQI (US)
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
34AQI (US)
43AQI (US)
36AQI (US)
30AQI (US)
36AQI (US)
27AQI (US)
40AQI (US)
45AQI (US)
No. of days
Jan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.Total Days
202636AQI (US)
26
5
26
2
30
1
28
26
4
30
25
6
5
196
18
Highest AQI (US) recorded in
August45AQI (US)
Lowest AQI (US) recorded in
June27AQI (US)
202537AQI (US)
29
2
27
1
28
3
29
1
31
17
13
25
6
20
10
1
18
12
26
5
25
5
20
11
295
69
1
Highest AQI (US) recorded in
June47AQI (US)
Lowest AQI (US) recorded in
May26AQI (US)
202434AQI (US)
31
23
6
29
2
30
30
1
25
4
24
7
25
6
28
2
27
4
30
29
2
331
34
Highest AQI (US) recorded in
July40AQI (US)
Lowest AQI (US) recorded in
November27AQI (US)
202343AQI (US)
23
8
27
1
26
5
28
2
26
5
5
23
1
1
18
12
1
20
11
26
4
29
2
28
1
28
3
284
77
2
1
Highest AQI (US) recorded in
June74AQI (US)
Lowest AQI (US) recorded in
December30AQI (US)
202239AQI (US)
25
5
17
4
27
4
29
1
27
4
24
6
20
4
2
27
1
29
2
23
7
20
11
270
49
Highest AQI (US) recorded in
June44AQI (US)
Lowest AQI (US) recorded in
September33AQI (US)
202143AQI (US)
25
4
23
5
24
7
26
4
29
2
24
6
12
16
3
20
10
1
22
8
28
3
22
6
19
10
274
81
4
Highest AQI (US) recorded in
July58AQI (US)
Lowest AQI (US) recorded in
October35AQI (US)
202039AQI (US)
11
2
18
2
18
25
5
24
7
29
2
28
1
28
2
24
4
18
11
223
36
Highest AQI (US) recorded in
December44AQI (US)
Lowest AQI (US) recorded in
October34AQI (US)
Most & Least Polluted Years Over the Last 7 Years
Most Polluted Year Recorded
2023(Avg.)
43AQI (US)Least Polluted Year Recorded
2024(Avg.)
34AQI (US)Decatur's annual 2026 AQI (US) (36) shows an average percentage change of -7.4% (improved AQI (US)) compared to previous years: 2020 (39), 2021 (43), 2022 (39), 2023 (43), 2024 (34), 2025 (37).
