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San Marcos, Texas, 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+

October Air Quality Analysis

San Marcos, Texas, United States

2025
AQI
.
Days

AQI Trends: Highest and Lowest

Highest AQI recorded on
3rd Oct 2025
67AQI
Lowest AQI recorded on
6th Oct 2025
47AQI

Same Day Analysis (13th October ):
On this day, AQI across the 1 years varied significantly: 2025 ranks 1st highest AQI at 51 of Moderate air quality on the same day.

Download 2024 Annual Data

World Air Quality Report

Globe

Day & Night AQI Trend: 13th Oct - 14th Oct 2025

San Marcos, Texas, United States

AQI
Day
Night
.

7 AM13th Oct 2025

7 PM

6 AM14th Oct 2025

Day time
Avg. Highest Time
11AM13th Oct

76AQI

Avg. Lowest Time
7AM13th Oct

40AQI

Night time
Avg. Highest Time
11PM13th Oct

63AQI

Avg. Lowest Time
4AM14th Oct

44AQI

In the last 24 hours,

San Marcos's AQI reached its highest point of 76 at 11 AM during the Day, while the lowest point, 40, was recorded at 7 AM during the Day between 13th Oct and 14th Oct 2025.

Day & Night AQI Trend : Sep - Oct 2025

San Marcos, Texas, United States

SepOct
14th - 15th15th - 16th16th - 17th17th - 18th18th - 19th19th - 20th20th - 21st21st - 22nd22nd - 23rd23rd - 24th24th - 25th25th - 26th26th - 27th27th - 28th28th - 29th29th - 30th30th - 01st01st - 02nd02nd - 03rd03rd - 04th04th - 05th05th - 06th06th - 07th07th - 08th08th - 09th09th - 10th10th - 11th11th - 12th12th - 13th13th - 14th14th
Day
Night
14th Sep 2025407 AMAQI
14th Sep 2025348 AMAQI
14th Sep 2025329 AMAQI
14th Sep 20254010 AMAQI
14th Sep 20255211 AMAQI
14th Sep 20255312 PMAQI
14th Sep 2025541 PMAQI
14th Sep 2025532 PMAQI
14th Sep 2025513 PMAQI
14th Sep 2025504 PMAQI
14th Sep 2025475 PMAQI
14th Sep 2025506 PMAQI
14th Sep 2025467 PMAQI
14th Sep 2025448 PMAQI
14th Sep 2025469 PMAQI
14th Sep 20254710 PMAQI
14th Sep 20255211 PMAQI
15th Sep 20255212 AMAQI
15th Sep 2025541 AMAQI
15th Sep 2025532 AMAQI
15th Sep 2025533 AMAQI
15th Sep 2025524 AMAQI
15th Sep 2025525 AMAQI
15th Sep 2025526 AMAQI

29°C21/38°C

15th Sep 2025547 AMAQI
15th Sep 2025488 AMAQI
15th Sep 2025589 AMAQI
15th Sep 20255310 AMAQI
15th Sep 20255611 AMAQI
15th Sep 20255712 PMAQI
15th Sep 2025591 PMAQI
15th Sep 2025592 PMAQI
15th Sep 2025603 PMAQI
15th Sep 2025584 PMAQI
15th Sep 2025585 PMAQI
15th Sep 2025566 PMAQI
15th Sep 2025537 PMAQI
15th Sep 2025518 PMAQI
15th Sep 2025489 PMAQI
15th Sep 20253910 PMAQI
15th Sep 20254011 PMAQI
16th Sep 20254012 AMAQI
16th Sep 2025401 AMAQI
16th Sep 2025342 AMAQI
16th Sep 2025313 AMAQI
16th Sep 2025304 AMAQI
16th Sep 2025295 AMAQI
16th Sep 2025336 AMAQI

29°C22/38°C

16th Sep 2025377 AMAQI
16th Sep 2025368 AMAQI
16th Sep 2025349 AMAQI
16th Sep 20254410 AMAQI
16th Sep 20255211 AMAQI
16th Sep 20255412 PMAQI
16th Sep 2025531 PMAQI
16th Sep 2025522 PMAQI
16th Sep 2025523 PMAQI
16th Sep 2025484 PMAQI
16th Sep 2025495 PMAQI
16th Sep 2025506 PMAQI
16th Sep 2025447 PMAQI
16th Sep 2025468 PMAQI
16th Sep 2025529 PMAQI
16th Sep 20255310 PMAQI
16th Sep 20255211 PMAQI
17th Sep 20255412 AMAQI
17th Sep 2025531 AMAQI
17th Sep 2025522 AMAQI
17th Sep 2025513 AMAQI
17th Sep 2025504 AMAQI
17th Sep 2025445 AMAQI
17th Sep 2025436 AMAQI

29°C21/37°C

17th Sep 2025477 AMAQI
17th Sep 2025468 AMAQI
17th Sep 2025489 AMAQI
17th Sep 20254810 AMAQI
17th Sep 20255011 AMAQI
17th Sep 20254712 PMAQI
17th Sep 2025481 PMAQI
17th Sep 2025522 PMAQI
17th Sep 2025523 PMAQI
17th Sep 2025514 PMAQI
17th Sep 2025475 PMAQI
17th Sep 2025466 PMAQI
17th Sep 2025517 PMAQI
17th Sep 2025508 PMAQI
17th Sep 2025489 PMAQI
17th Sep 20254510 PMAQI
17th Sep 20254811 PMAQI
18th Sep 20255012 AMAQI
18th Sep 2025461 AMAQI
18th Sep 2025402 AMAQI
18th Sep 2025383 AMAQI
18th Sep 2025414 AMAQI
18th Sep 2025385 AMAQI
18th Sep 2025366 AMAQI

28°C21/37°C

18th Sep 2025367 AMAQI
18th Sep 2025388 AMAQI
18th Sep 2025369 AMAQI
18th Sep 20254310 AMAQI
18th Sep 20255211 AMAQI
18th Sep 20255012 PMAQI
18th Sep 2025511 PMAQI
18th Sep 2025552 PMAQI
18th Sep 2025553 PMAQI
18th Sep 2025544 PMAQI
18th Sep 2025545 PMAQI
18th Sep 2025526 PMAQI
18th Sep 2025497 PMAQI
18th Sep 2025468 PMAQI
18th Sep 2025489 PMAQI
18th Sep 20255010 PMAQI
18th Sep 20255111 PMAQI
19th Sep 20254912 AMAQI
19th Sep 2025501 AMAQI
19th Sep 2025482 AMAQI
19th Sep 2025433 AMAQI
19th Sep 2025394 AMAQI
19th Sep 2025345 AMAQI
19th Sep 2025366 AMAQI

29°C22/37°C

19th Sep 2025357 AMAQI
19th Sep 2025338 AMAQI
19th Sep 2025339 AMAQI
19th Sep 20253610 AMAQI
19th Sep 20254311 AMAQI
19th Sep 20254612 PMAQI
19th Sep 2025451 PMAQI
19th Sep 2025472 PMAQI
19th Sep 2025483 PMAQI
19th Sep 2025504 PMAQI
19th Sep 2025515 PMAQI
19th Sep 2025526 PMAQI
19th Sep 2025487 PMAQI
19th Sep 2025468 PMAQI
19th Sep 2025449 PMAQI
19th Sep 20254410 PMAQI
19th Sep 20254211 PMAQI
20th Sep 20254212 AMAQI
20th Sep 2025441 AMAQI
20th Sep 2025342 AMAQI
20th Sep 2025303 AMAQI
20th Sep 2025274 AMAQI
20th Sep 2025235 AMAQI
20th Sep 2025216 AMAQI

29°C23/37°C

20th Sep 2025237 AMAQI
20th Sep 2025238 AMAQI
20th Sep 2025259 AMAQI
20th Sep 20252510 AMAQI
20th Sep 20253311 AMAQI
20th Sep 20253212 PMAQI
20th Sep 2025341 PMAQI
20th Sep 2025342 PMAQI
20th Sep 2025333 PMAQI
20th Sep 2025354 PMAQI
20th Sep 2025395 PMAQI
20th Sep 2025406 PMAQI
20th Sep 2025347 PMAQI
20th Sep 2025328 PMAQI
20th Sep 2025319 PMAQI
20th Sep 20253410 PMAQI
20th Sep 20253211 PMAQI
21st Sep 20253212 AMAQI
21st Sep 2025291 AMAQI
21st Sep 2025202 AMAQI
21st Sep 2025203 AMAQI
21st Sep 2025184 AMAQI
21st Sep 2025215 AMAQI
21st Sep 2025236 AMAQI

28°C22/37°C

21st Sep 2025217 AMAQI
21st Sep 2025198 AMAQI
21st Sep 2025189 AMAQI
21st Sep 20252110 AMAQI
21st Sep 20252711 AMAQI
21st Sep 20252612 PMAQI
21st Sep 2025241 PMAQI
21st Sep 2025242 PMAQI
21st Sep 2025253 PMAQI
21st Sep 2025264 PMAQI
21st Sep 2025265 PMAQI
21st Sep 2025316 PMAQI
21st Sep 2025267 PMAQI
21st Sep 2025268 PMAQI
21st Sep 2025269 PMAQI
21st Sep 20252610 PMAQI
21st Sep 20252211 PMAQI
22nd Sep 20252012 AMAQI
22nd Sep 2025181 AMAQI
22nd Sep 2025182 AMAQI
22nd Sep 2025183 AMAQI
22nd Sep 2025164 AMAQI
22nd Sep 2025165 AMAQI
22nd Sep 2025166 AMAQI

29°C24/38°C

22nd Sep 2025147 AMAQI
22nd Sep 2025168 AMAQI
22nd Sep 2025189 AMAQI
22nd Sep 20251710 AMAQI
22nd Sep 20252011 AMAQI
22nd Sep 20251812 PMAQI
22nd Sep 2025181 PMAQI
22nd Sep 2025222 PMAQI
22nd Sep 2025223 PMAQI
22nd Sep 2025204 PMAQI
22nd Sep 2025195 PMAQI
22nd Sep 2025196 PMAQI
22nd Sep 2025197 PMAQI
22nd Sep 2025208 PMAQI
22nd Sep 2025229 PMAQI
22nd Sep 20251610 PMAQI
22nd Sep 20251611 PMAQI
23rd Sep 20251812 AMAQI
23rd Sep 2025181 AMAQI
23rd Sep 2025162 AMAQI
23rd Sep 2025143 AMAQI
23rd Sep 2025154 AMAQI
23rd Sep 2025165 AMAQI
23rd Sep 2025166 AMAQI

30°C25/38°C

23rd Sep 2025157 AMAQI
23rd Sep 2025188 AMAQI
23rd Sep 2025189 AMAQI
23rd Sep 20251810 AMAQI
23rd Sep 20252011 AMAQI
23rd Sep 20252112 PMAQI
23rd Sep 2025201 PMAQI
23rd Sep 2025192 PMAQI
23rd Sep 2025223 PMAQI
23rd Sep 2025244 PMAQI
23rd Sep 2025255 PMAQI
23rd Sep 2025316 PMAQI
23rd Sep 2025207 PMAQI
23rd Sep 2025188 PMAQI
23rd Sep 2025189 PMAQI
23rd Sep 20251610 PMAQI
23rd Sep 20251811 PMAQI
24th Sep 20251912 AMAQI
24th Sep 2025181 AMAQI
24th Sep 2025182 AMAQI
24th Sep 2025203 AMAQI
24th Sep 2025194 AMAQI
24th Sep 2025195 AMAQI
24th Sep 2025216 AMAQI

31°C26/38°C

24th Sep 2025197 AMAQI
24th Sep 2025188 AMAQI
24th Sep 2025229 AMAQI
24th Sep 20252610 AMAQI
24th Sep 20252611 AMAQI
24th Sep 20252912 PMAQI
24th Sep 2025321 PMAQI
24th Sep 2025272 PMAQI
24th Sep 2025203 PMAQI
24th Sep 2025224 PMAQI
24th Sep 2025225 PMAQI
24th Sep 2025196 PMAQI
24th Sep 2025227 PMAQI
24th Sep 2025208 PMAQI
24th Sep 2025179 PMAQI
24th Sep 20251610 PMAQI
24th Sep 20251811 PMAQI
25th Sep 20252412 AMAQI
25th Sep 2025271 AMAQI
25th Sep 2025242 AMAQI
25th Sep 2025223 AMAQI
25th Sep 2025224 AMAQI
25th Sep 2025235 AMAQI
25th Sep 2025276 AMAQI

29°C26/35°C

25th Sep 2025287 AMAQI
25th Sep 2025308 AMAQI
25th Sep 2025339 AMAQI
25th Sep 20253310 AMAQI
25th Sep 20252811 AMAQI
25th Sep 20253412 PMAQI
25th Sep 2025391 PMAQI
25th Sep 2025402 PMAQI
25th Sep 2025383 PMAQI
25th Sep 2025384 PMAQI
25th Sep 2025405 PMAQI
25th Sep 2025406 PMAQI
25th Sep 2025407 PMAQI
25th Sep 2025398 PMAQI
25th Sep 2025389 PMAQI
25th Sep 20253410 PMAQI
25th Sep 20253211 PMAQI
26th Sep 20253012 AMAQI
26th Sep 2025291 AMAQI
26th Sep 2025322 AMAQI
26th Sep 2025313 AMAQI
26th Sep 2025324 AMAQI
26th Sep 2025325 AMAQI
26th Sep 2025376 AMAQI

28°C22/34°C

26th Sep 2025387 AMAQI
26th Sep 2025408 AMAQI
26th Sep 2025409 AMAQI
26th Sep 20253710 AMAQI
26th Sep 20254511 AMAQI
26th Sep 20254512 PMAQI
26th Sep 2025451 PMAQI
26th Sep 2025472 PMAQI
26th Sep 2025493 PMAQI
26th Sep 2025494 PMAQI
26th Sep 2025505 PMAQI
26th Sep 2025516 PMAQI
26th Sep 2025507 PMAQI
26th Sep 2025488 PMAQI
26th Sep 2025429 PMAQI
26th Sep 20253510 PMAQI
26th Sep 20253311 PMAQI
27th Sep 20254712 AMAQI
27th Sep 2025481 AMAQI
27th Sep 2025442 AMAQI
27th Sep 2025503 AMAQI
27th Sep 2025404 AMAQI
27th Sep 2025445 AMAQI
27th Sep 2025476 AMAQI

27°C18/36°C

27th Sep 2025527 AMAQI
27th Sep 2025508 AMAQI
27th Sep 2025509 AMAQI
27th Sep 20255310 AMAQI
27th Sep 20255511 AMAQI
27th Sep 20255112 PMAQI
27th Sep 2025351 PMAQI
27th Sep 2025372 PMAQI
27th Sep 2025343 PMAQI
27th Sep 2025274 PMAQI
27th Sep 2025305 PMAQI
27th Sep 2025366 PMAQI
27th Sep 2025317 PMAQI
27th Sep 2025318 PMAQI
27th Sep 2025329 PMAQI
27th Sep 20253810 PMAQI
27th Sep 20253511 PMAQI
28th Sep 20253912 AMAQI
28th Sep 2025341 AMAQI
28th Sep 2025402 AMAQI
28th Sep 2025423 AMAQI
28th Sep 2025414 AMAQI
28th Sep 2025355 AMAQI
28th Sep 2025356 AMAQI

26°C17/36°C

28th Sep 2025357 AMAQI
28th Sep 2025398 AMAQI
28th Sep 2025419 AMAQI
28th Sep 20254810 AMAQI
28th Sep 20255111 AMAQI
28th Sep 20254912 PMAQI
28th Sep 2025471 PMAQI
28th Sep 2025462 PMAQI
28th Sep 2025443 PMAQI
28th Sep 2025374 PMAQI
28th Sep 2025375 PMAQI
28th Sep 2025416 PMAQI
28th Sep 2025517 PMAQI
28th Sep 2025418 PMAQI
28th Sep 2025449 PMAQI
28th Sep 20255010 PMAQI
28th Sep 20254911 PMAQI
29th Sep 20254712 AMAQI
29th Sep 2025491 AMAQI
29th Sep 2025452 AMAQI
29th Sep 2025473 AMAQI
29th Sep 2025344 AMAQI
29th Sep 2025345 AMAQI
29th Sep 2025486 AMAQI

26°C17/35°C

29th Sep 2025517 AMAQI
29th Sep 2025468 AMAQI
29th Sep 2025409 AMAQI
29th Sep 20253210 AMAQI
29th Sep 20255211 AMAQI
29th Sep 20253712 PMAQI
29th Sep 2025421 PMAQI
29th Sep 2025372 PMAQI
29th Sep 2025313 PMAQI
29th Sep 2025284 PMAQI
29th Sep 2025255 PMAQI
29th Sep 2025236 PMAQI
29th Sep 2025207 PMAQI
29th Sep 2025358 PMAQI
29th Sep 2025379 PMAQI
29th Sep 20254210 PMAQI
29th Sep 20254111 PMAQI
30th Sep 20253312 AMAQI
30th Sep 2025331 AMAQI
30th Sep 2025322 AMAQI
30th Sep 2025353 AMAQI
30th Sep 2025484 AMAQI
30th Sep 2025365 AMAQI
30th Sep 2025236 AMAQI

26°C17/35°C

30th Sep 2025277 AMAQI
30th Sep 2025288 AMAQI
30th Sep 2025289 AMAQI
30th Sep 20253210 AMAQI
30th Sep 20253011 AMAQI
30th Sep 20253312 PMAQI
30th Sep 2025331 PMAQI
30th Sep 2025442 PMAQI
30th Sep 2025423 PMAQI
30th Sep 2025414 PMAQI
30th Sep 2025495 PMAQI
30th Sep 2025436 PMAQI
30th Sep 2025397 PMAQI
30th Sep 2025368 PMAQI
30th Sep 2025379 PMAQI
30th Sep 20254610 PMAQI
30th Sep 20255311 PMAQI
1st Oct 20255012 AMAQI
1st Oct 2025501 AMAQI
1st Oct 2025552 AMAQI
1st Oct 2025573 AMAQI
1st Oct 2025584 AMAQI
1st Oct 2025585 AMAQI
1st Oct 2025566 AMAQI

28°C18/37°C

1st Oct 2025567 AMAQI
1st Oct 2025568 AMAQI
1st Oct 2025589 AMAQI
1st Oct 20256210 AMAQI
1st Oct 20256511 AMAQI
1st Oct 20257012 PMAQI
1st Oct 2025691 PMAQI
1st Oct 2025652 PMAQI
1st Oct 2025583 PMAQI
1st Oct 2025564 PMAQI
1st Oct 2025565 PMAQI
1st Oct 2025586 PMAQI
1st Oct 2025577 PMAQI
1st Oct 2025578 PMAQI
1st Oct 2025589 PMAQI
1st Oct 20255710 PMAQI
1st Oct 20255911 PMAQI
2nd Oct 20255812 AMAQI
2nd Oct 2025591 AMAQI
2nd Oct 2025592 AMAQI
2nd Oct 2025583 AMAQI
2nd Oct 2025584 AMAQI
2nd Oct 2025635 AMAQI
2nd Oct 2025646 AMAQI

27°C18/37°C

2nd Oct 2025667 AMAQI
2nd Oct 2025768 AMAQI
2nd Oct 2025789 AMAQI
2nd Oct 20257910 AMAQI
2nd Oct 20258411 AMAQI
2nd Oct 20258012 PMAQI
2nd Oct 2025711 PMAQI
2nd Oct 2025642 PMAQI
2nd Oct 2025583 PMAQI
2nd Oct 2025594 PMAQI
2nd Oct 2025595 PMAQI
2nd Oct 2025596 PMAQI
2nd Oct 2025587 PMAQI
2nd Oct 2025578 PMAQI
2nd Oct 2025609 PMAQI
2nd Oct 20256210 PMAQI
2nd Oct 20256711 PMAQI
3rd Oct 20256512 AMAQI
3rd Oct 2025671 AMAQI
3rd Oct 2025642 AMAQI
3rd Oct 2025623 AMAQI
3rd Oct 2025604 AMAQI
3rd Oct 2025605 AMAQI
3rd Oct 2025546 AMAQI

28°C18/37°C

3rd Oct 2025657 AMAQI
3rd Oct 2025658 AMAQI
3rd Oct 2025679 AMAQI
3rd Oct 20256910 AMAQI
3rd Oct 20257411 AMAQI
3rd Oct 20257512 PMAQI
3rd Oct 2025781 PMAQI
3rd Oct 2025742 PMAQI
3rd Oct 2025753 PMAQI
3rd Oct 2025704 PMAQI
3rd Oct 2025685 PMAQI
3rd Oct 2025676 PMAQI
3rd Oct 2025677 PMAQI
3rd Oct 2025688 PMAQI
3rd Oct 2025699 PMAQI
3rd Oct 20256810 PMAQI
3rd Oct 20256711 PMAQI
4th Oct 20256512 AMAQI
4th Oct 2025601 AMAQI
4th Oct 2025622 AMAQI
4th Oct 2025633 AMAQI
4th Oct 2025554 AMAQI
4th Oct 2025555 AMAQI
4th Oct 2025526 AMAQI

28°C20/36°C

4th Oct 2025547 AMAQI
4th Oct 2025548 AMAQI
4th Oct 2025539 AMAQI
4th Oct 20255410 AMAQI
4th Oct 20255711 AMAQI
4th Oct 20255512 PMAQI
4th Oct 2025581 PMAQI
4th Oct 2025622 PMAQI
4th Oct 2025663 PMAQI
4th Oct 2025654 PMAQI
4th Oct 2025625 PMAQI
4th Oct 2025546 PMAQI
4th Oct 2025567 PMAQI
4th Oct 2025568 PMAQI
4th Oct 2025559 PMAQI
4th Oct 20255910 PMAQI
4th Oct 20255811 PMAQI
5th Oct 20255712 AMAQI
5th Oct 2025581 AMAQI
5th Oct 2025542 AMAQI
5th Oct 2025553 AMAQI
5th Oct 2025524 AMAQI
5th Oct 2025505 AMAQI
5th Oct 2025476 AMAQI

27°C19/35°C

5th Oct 2025447 AMAQI
5th Oct 2025458 AMAQI
5th Oct 2025469 AMAQI
5th Oct 20254510 AMAQI
5th Oct 20254711 AMAQI
5th Oct 20254812 PMAQI
5th Oct 2025531 PMAQI
5th Oct 2025522 PMAQI
5th Oct 2025533 PMAQI
5th Oct 2025464 PMAQI
5th Oct 2025495 PMAQI
5th Oct 2025466 PMAQI
5th Oct 2025467 PMAQI
5th Oct 2025488 PMAQI
5th Oct 2025489 PMAQI
5th Oct 20255210 PMAQI
5th Oct 20255511 PMAQI
6th Oct 20255212 AMAQI
6th Oct 2025481 AMAQI
6th Oct 2025482 AMAQI
6th Oct 2025443 AMAQI
6th Oct 2025464 AMAQI
6th Oct 2025445 AMAQI
6th Oct 2025506 AMAQI

27°C20/33°C

6th Oct 2025517 AMAQI
6th Oct 2025478 AMAQI
6th Oct 2025509 AMAQI
6th Oct 20255310 AMAQI
6th Oct 20256711 AMAQI
6th Oct 20256412 PMAQI
7th Oct 2025456 AMAQI

27°C20/36°C

7th Oct 2025407 AMAQI
7th Oct 2025468 AMAQI
7th Oct 2025449 AMAQI
7th Oct 20254410 AMAQI
7th Oct 20254611 AMAQI
7th Oct 20254212 PMAQI
7th Oct 2025431 PMAQI
7th Oct 2025462 PMAQI
7th Oct 2025483 PMAQI
7th Oct 2025524 PMAQI
7th Oct 2025485 PMAQI
7th Oct 2025526 PMAQI
7th Oct 2025517 PMAQI
7th Oct 2025538 PMAQI
7th Oct 2025529 PMAQI
7th Oct 20255310 PMAQI
7th Oct 20254611 PMAQI
8th Oct 20255012 AMAQI
8th Oct 2025471 AMAQI
8th Oct 2025522 AMAQI
8th Oct 2025523 AMAQI
8th Oct 2025474 AMAQI
8th Oct 2025505 AMAQI
8th Oct 2025476 AMAQI

28°C22/36°C

8th Oct 2025547 AMAQI
8th Oct 2025518 AMAQI
8th Oct 2025489 AMAQI
8th Oct 20255210 AMAQI
8th Oct 20255011 AMAQI
8th Oct 20254912 PMAQI
8th Oct 2025521 PMAQI
8th Oct 2025552 PMAQI
8th Oct 2025553 PMAQI
8th Oct 2025524 PMAQI
8th Oct 2025465 PMAQI
8th Oct 2025446 PMAQI
8th Oct 2025457 PMAQI
8th Oct 2025478 PMAQI
8th Oct 2025449 PMAQI
8th Oct 20254710 PMAQI
8th Oct 20255011 PMAQI
9th Oct 20254912 AMAQI
9th Oct 2025511 AMAQI
9th Oct 2025472 AMAQI
9th Oct 2025513 AMAQI
9th Oct 2025494 AMAQI
9th Oct 2025475 AMAQI
9th Oct 2025486 AMAQI

29°C23/37°C

9th Oct 2025467 AMAQI
9th Oct 2025458 AMAQI
9th Oct 2025469 AMAQI
9th Oct 20254810 AMAQI
9th Oct 20254611 AMAQI
9th Oct 20254912 PMAQI
9th Oct 2025551 PMAQI
9th Oct 2025552 PMAQI
9th Oct 2025573 PMAQI
9th Oct 2025574 PMAQI
9th Oct 2025545 PMAQI
9th Oct 2025536 PMAQI
9th Oct 2025507 PMAQI
9th Oct 2025488 PMAQI
9th Oct 2025529 PMAQI
9th Oct 20255310 PMAQI
9th Oct 20255211 PMAQI
10th Oct 20255512 AMAQI
10th Oct 2025521 AMAQI
10th Oct 2025542 AMAQI
10th Oct 2025533 AMAQI
10th Oct 2025534 AMAQI
10th Oct 2025515 AMAQI
10th Oct 2025496 AMAQI

28°C23/35°C

10th Oct 2025487 AMAQI
10th Oct 2025508 AMAQI
10th Oct 2025539 AMAQI
10th Oct 20255410 AMAQI
10th Oct 20255711 AMAQI
10th Oct 20255812 PMAQI
10th Oct 2025621 PMAQI
10th Oct 2025632 PMAQI
10th Oct 2025633 PMAQI
10th Oct 2025604 PMAQI
10th Oct 2025595 PMAQI
10th Oct 2025556 PMAQI
10th Oct 2025507 PMAQI
10th Oct 2025528 PMAQI
10th Oct 2025539 PMAQI
10th Oct 20255810 PMAQI
10th Oct 20255811 PMAQI
11th Oct 20255912 AMAQI
11th Oct 2025571 AMAQI
11th Oct 2025542 AMAQI
11th Oct 2025543 AMAQI
11th Oct 2025544 AMAQI
11th Oct 2025545 AMAQI
11th Oct 2025546 AMAQI

27°C20/36°C

11th Oct 2025517 AMAQI
11th Oct 2025528 AMAQI
11th Oct 2025539 AMAQI
11th Oct 20255310 AMAQI
11th Oct 20255711 AMAQI
11th Oct 20256112 PMAQI
11th Oct 2025591 PMAQI
11th Oct 2025602 PMAQI
11th Oct 2025583 PMAQI
11th Oct 2025604 PMAQI
11th Oct 2025565 PMAQI
11th Oct 2025546 PMAQI
11th Oct 2025527 PMAQI
11th Oct 2025548 PMAQI
11th Oct 2025559 PMAQI
11th Oct 20255610 PMAQI
11th Oct 20256011 PMAQI
12th Oct 20256112 AMAQI
12th Oct 2025621 AMAQI
12th Oct 2025582 AMAQI
12th Oct 2025583 AMAQI
12th Oct 2025564 AMAQI
12th Oct 2025545 AMAQI
12th Oct 2025526 AMAQI

26°C17/36°C

12th Oct 2025517 AMAQI
12th Oct 2025488 AMAQI
12th Oct 2025489 AMAQI
12th Oct 20255010 AMAQI
12th Oct 20255311 AMAQI
12th Oct 20255312 PMAQI
12th Oct 2025541 PMAQI
12th Oct 2025532 PMAQI
12th Oct 2025543 PMAQI
12th Oct 2025554 PMAQI
12th Oct 2025555 PMAQI
12th Oct 2025556 PMAQI
12th Oct 2025547 PMAQI
12th Oct 2025568 PMAQI
12th Oct 2025569 PMAQI
12th Oct 20255510 PMAQI
12th Oct 20255811 PMAQI
13th Oct 20255512 AMAQI
13th Oct 2025491 AMAQI
13th Oct 2025442 AMAQI
13th Oct 2025463 AMAQI
13th Oct 2025444 AMAQI
13th Oct 2025385 AMAQI
13th Oct 2025406 AMAQI

26°C17/34°C

13th Oct 2025407 AMAQI
13th Oct 2025418 AMAQI
13th Oct 2025439 AMAQI
13th Oct 20255210 AMAQI
13th Oct 20257611 AMAQI
13th Oct 20257212 PMAQI
13th Oct 2025561 PMAQI
13th Oct 2025482 PMAQI
13th Oct 2025503 PMAQI
13th Oct 2025514 PMAQI
13th Oct 2025555 PMAQI
13th Oct 2025766 PMAQI
13th Oct 2025557 PMAQI
13th Oct 2025508 PMAQI
13th Oct 2025529 PMAQI
13th Oct 20255310 PMAQI
13th Oct 20256311 PMAQI
14th Oct 20255912 AMAQI
14th Oct 2025551 AMAQI
14th Oct 2025552 AMAQI
14th Oct 2025523 AMAQI
14th Oct 2025444 AMAQI
14th Oct 2025485 AMAQI
14th Oct 2025456 AMAQI

25°C17/34°C

14th Oct 2025507 AMAQI
7 AM
14th Oct 2025538 AMAQI
14th Oct 2025529 AMAQI
14th Oct 20255610 AMAQI
14th Oct 20256011 AMAQI
14th Oct 20255812 PMAQI
14th Oct 2025521 PMAQI
1 PM
7 PM
1 AM
6 AM

--°C/°C

Day time
Avg. Highest Time
11 AM - 6 PM

48AQI

8 hours / Day
240 hours / Month
Avg. Lowest Time
7 AM - 9 AM

42AQI

3 hours / Day
90 hours / Month
In the last 30 days, during the daytime, the highest AQI was between 11 AM to 6 PM (Avg. 48), while the lowest AQI was between 7 AM to 9 AM (Avg. 42).
Night time
Avg. Highest Time
12 AM - 1 AM

46AQI

2 hours / Day
60 hours / Month
Avg. Lowest Time
5 AM - 6 AM

41AQI

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. 46), while the lowest AQI was between 5 AM to 6 AM (Avg. 41).

2025 Days Vs Air Quality

San Marcos, Texas, United States

2025

75%

152

25%

50

Total number of days with different AQI categories in last 287 days in 2025 (78 days remaining)

Good
152 Days
Moderate
50 Days
Poor
0 Days
Unhealthy
0 Days
Severe
0 Days
Hazardous
0 Days

Under WHO’s Safe Air Quality Limits: 75%

Health Risk Level:

Low

In 2025, 75% of 287 days were within WHO’s safe air quality limits. The risk of health issues is Low, but the long-term effects, especially on vulnerable individuals, remain uncertain.

Annual Air Quality Insights

San Marcos, Texas, United States

AQI levels in 2025

AQI
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 2025
-1th undefined 2025
-1th undefined 2025
1st January 2025
2nd January 2025
3rd January 2025
4th January 2025
5th January 2025
6th January 2025
7th January 2025
8th January 2025
9th January 2025
10th January 2025
11th January 2025
12th January 2025
13th January 2025
14th January 2025
15th January 2025
16th January 2025
17th January 2025
18th January 2025
19th January 2025
20th January 2025
21st January 2025
22nd January 2025
23rd January 2025
24th January 2025
25th January 2025
26th January 2025
27th January 2025
28th January 2025
29th January 2025
30th January 2025
31st January 2025
1st February 2025
2nd February 2025
3rd February 2025
4th February 2025
5th February 2025
6th February 2025
7th February 2025
8th February 2025
9th February 2025
10th February 2025
11th February 2025
12th February 2025
13th February 2025
14th February 2025
15th February 2025
16th February 2025
17th February 2025
18th February 2025
19th February 2025
20th February 2025
21st February 2025
22nd February 2025
23rd February 2025
24th February 2025
25th February 2025
26th February 2025
27th February 2025
28th February 2025
1st March 2025
2nd March 2025
3rd March 2025
4th March 2025
5th March 2025
6th March 2025
7th March 2025
8th March 2025
9th March 2025
10th March 2025
11th March 2025
12th March 2025
13th March 2025
14th March 2025
15th March 2025
16th March 2025
17th March 2025
18th March 2025
19th March 2025
20th March 2025
21st March 2025
22nd March 2025
23rd March 2025
24th March 2025
25th March 2025
26th March 2025
30AQI
27th March 2025
26AQI
28th March 2025
26AQI
29th March 2025
42AQI
30th March 2025
68AQI
31st March 2025
59AQI
1st April 2025
54AQI
2nd April 2025
64AQI
3rd April 2025
71AQI
4th April 2025
61AQI
5th April 2025
30AQI
6th April 2025
20AQI
7th April 2025
22AQI
8th April 2025
31AQI
9th April 2025
36AQI
10th April 2025
40AQI
11th April 2025
42AQI
12th April 2025
50AQI
13th April 2025
40AQI
14th April 2025
42AQI
15th April 2025
46AQI
16th April 2025
46AQI
17th April 2025
40AQI
18th April 2025
54AQI
19th April 2025
62AQI
20th April 2025
38AQI
21st April 2025
26AQI
22nd April 2025
43AQI
23rd April 2025
41AQI
24th April 2025
55AQI
25th April 2025
50AQI
26th April 2025
58AQI
27th April 2025
48AQI
28th April 2025
51AQI
29th April 2025
45AQI
30th April 2025
53AQI
1st May 2025
57AQI
2nd May 2025
43AQI
3rd May 2025
28AQI
4th May 2025
28AQI
5th May 2025
33AQI
6th May 2025
47AQI
7th May 2025
40AQI
8th May 2025
42AQI
9th May 2025
26AQI
10th May 2025
33AQI
11th May 2025
37AQI
12th May 2025
33AQI
13th May 2025
39AQI
14th May 2025
47AQI
15th May 2025
61AQI
16th May 2025
66AQI
17th May 2025
69AQI
18th May 2025
56AQI
19th May 2025
62AQI
20th May 2025
67AQI
21st May 2025
54AQI
22nd May 2025
58AQI
23rd May 2025
48AQI
24th May 2025
54AQI
25th May 2025
58AQI
26th May 2025
58AQI
27th May 2025
34AQI
28th May 2025
33AQI
29th May 2025
34AQI
30th May 2025
36AQI
31st May 2025
43AQI
1st June 2025
47AQI
2nd June 2025
50AQI
3rd June 2025
58AQI
4th June 2025
54AQI
5th June 2025
50AQI
6th June 2025
54AQI
7th June 2025
60AQI
8th June 2025
57AQI
9th June 2025
48AQI
10th June 2025
43AQI
11th June 2025
32AQI
12th June 2025
26AQI
13th June 2025
42AQI
14th June 2025
54AQI
15th June 2025
49AQI
16th June 2025
32AQI
17th June 2025
37AQI
18th June 2025
56AQI
19th June 2025
53AQI
20th June 2025
50AQI
21st June 2025
32AQI
22nd June 2025
37AQI
23rd June 2025
44AQI
24th June 2025
29AQI
25th June 2025
23AQI
26th June 2025
26AQI
27th June 2025
22AQI
28th June 2025
22AQI
29th June 2025
23AQI
30th June 2025
45AQI
1st July 2025
46AQI
2nd July 2025
53AQI
3rd July 2025
40AQI
4th July 2025
47AQI
5th July 2025
61AQI
6th July 2025
60AQI
7th July 2025
54AQI
8th July 2025
45AQI
9th July 2025
33AQI
10th July 2025
42AQI
11th July 2025
47AQI
12th July 2025
38AQI
13th July 2025
30AQI
14th July 2025
33AQI
15th July 2025
49AQI
16th July 2025
60AQI
17th July 2025
62AQI
18th July 2025
47AQI
19th July 2025
44AQI
20th July 2025
42AQI
21st July 2025
48AQI
22nd July 2025
39AQI
23rd July 2025
34AQI
24th July 2025
27AQI
25th July 2025
27AQI
26th July 2025
30AQI
27th July 2025
36AQI
28th July 2025
44AQI
29th July 2025
58AQI
30th July 2025
54AQI
31st July 2025
48AQI
1st August 2025
32AQI
2nd August 2025
31AQI
3rd August 2025
34AQI
4th August 2025
30AQI
5th August 2025
33AQI
6th August 2025
35AQI
7th August 2025
35AQI
8th August 2025
36AQI
9th August 2025
37AQI
10th August 2025
28AQI
11th August 2025
27AQI
12th August 2025
30AQI
13th August 2025
32AQI
14th August 2025
49AQI
15th August 2025
31AQI
16th August 2025
36AQI
17th August 2025
54AQI
18th August 2025
29AQI
19th August 2025
31AQI
20th August 2025
34AQI
21st August 2025
37AQI
22nd August 2025
40AQI
23rd August 2025
39AQI
24th August 2025
45AQI
25th August 2025
47AQI
26th August 2025
41AQI
27th August 2025
44AQI
28th August 2025
47AQI
29th August 2025
44AQI
30th August 2025
41AQI
31st August 2025
30AQI
1st September 2025
32AQI
2nd September 2025
31AQI
3rd September 2025
36AQI
4th September 2025
36AQI
5th September 2025
33AQI
6th September 2025
31AQI
7th September 2025
49AQI
8th September 2025
46AQI
9th September 2025
44AQI
10th September 2025
40AQI
11th September 2025
38AQI
12th September 2025
36AQI
13th September 2025
46AQI
14th September 2025
46AQI
15th September 2025
52AQI
16th September 2025
43AQI
17th September 2025
49AQI
18th September 2025
46AQI
19th September 2025
44AQI
20th September 2025
32AQI
21st September 2025
24AQI
22nd September 2025
18AQI
23rd September 2025
19AQI
24th September 2025
21AQI
25th September 2025
32AQI
26th September 2025
40AQI
27th September 2025
41AQI
28th September 2025
42AQI
29th September 2025
38AQI
30th September 2025
37AQI
1st October 2025
58AQI
2nd October 2025
64AQI
3rd October 2025
67AQI
4th October 2025
58AQI
5th October 2025
50AQI
6th October 2025
47AQI
7th October 2025
48AQI
8th October 2025
49AQI
9th October 2025
50AQI
10th October 2025
55AQI
11th October 2025
55AQI
12th October 2025
55AQI
13th October 2025
51AQI
14th October 2025
15th October 2025
16th October 2025
17th October 2025
18th October 2025
19th October 2025
20th October 2025
21st October 2025
22nd October 2025
23rd October 2025
24th October 2025
25th October 2025
26th October 2025
27th October 2025
28th October 2025
29th October 2025
30th October 2025
31st October 2025
1st November 2025
2nd November 2025
3rd November 2025
4th November 2025
5th November 2025
6th November 2025
7th November 2025
8th November 2025
9th November 2025
10th November 2025
11th November 2025
12th November 2025
13th November 2025
14th November 2025
15th November 2025
16th November 2025
17th November 2025
18th November 2025
19th November 2025
20th November 2025
21st November 2025
22nd November 2025
23rd November 2025
24th November 2025
25th November 2025
26th November 2025
27th November 2025
28th November 2025
29th November 2025
30th November 2025
1st December 2025
2nd December 2025
3rd December 2025
4th December 2025
5th December 2025
6th December 2025
7th December 2025
8th December 2025
9th December 2025
10th December 2025
11th December 2025
12th December 2025
13th December 2025
14th December 2025
15th December 2025
16th December 2025
17th December 2025
18th December 2025
19th December 2025
20th December 2025
21st December 2025
22nd December 2025
23rd December 2025
24th December 2025
25th December 2025
26th December 2025
27th December 2025
28th December 2025
29th December 2025
30th December 2025
31st December 2025

42AQI

45AQI

46AQI

42AQI

44AQI

37AQI

37AQI

54AQI

No. of days

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

202543AQI

4
2
20
10
19
12
22
8
23
8
30
1
29
1
5
8
152
50

Highest AQI recorded in

October

54AQI

Lowest AQI recorded in

August

37AQI

Most & Least Polluted Years Over the Last 1 Years

Most Polluted Year Recorded
2025(Avg.)
43AQI
Least Polluted Year Recorded
2025(Avg.)
43AQI

San Marcos's annual 2025 AQI (43) shows an average percentage change of NaN% (improved AQI) compared to previous years: .