Country Background
HistoryAQIPM2.5PM10COSO2NO2O3

Guelph, Ontario, Canada 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

Guelph, Ontario, Canada

2021
2022
2023
2024
2025
AQI
.
Days

AQI Trends: Highest and Lowest

Highest AQI recorded on
4th Aug 2025
124AQI
Lowest AQI recorded on
18th Aug 2025
15AQI

Same Day Analysis (19th August ):
On this day, AQI across the 5 years varied significantly: 2025 ranks 4th highest AQI at 20 of Good air quality, showing improvement over 2024, 2023 and 2021 on the same day.

Download 2024 Annual Data

World Air Quality Report

Globe

Day & Night AQI Trend: 19th Aug - 20th Aug 2025

Guelph, Ontario, Canada

AQI
Day
Night
.

6 AM19th Aug 2025

8 PM

5 AM20th Aug 2025

Day time
Avg. Highest Time
8PM19th Aug

32AQI

Avg. Lowest Time
9AM19th Aug

17AQI

Night time
Avg. Highest Time
11PM19th Aug

29AQI

Avg. Lowest Time
5AM20th Aug

18AQI

In the last 24 hours,

Guelph's AQI reached its highest point of 32 at 8 PM during the Day, while the lowest point, 17, was recorded at 9 AM during the Day between 19th Aug and 20th Aug 2025.

Day & Night AQI Trend : Jul - Aug 2025

Guelph, Ontario, Canada

JulAug
21st - 22nd22nd - 23rd23rd - 24th24th - 25th25th - 26th26th - 27th27th - 28th28th - 29th29th - 30th30th - 31st31st - 01st01st - 02nd02nd - 03rd03rd - 04th04th - 05th05th - 06th06th - 07th07th - 08th08th - 09th09th - 10th10th - 11th11th - 12th12th - 13th13th - 14th14th - 15th15th - 16th16th - 17th17th - 18th18th - 19th19th - 20th20th
Day
Night
21st Jul 2025606 AMAQI
21st Jul 2025607 AMAQI
21st Jul 2025568 AMAQI
21st Jul 2025499 AMAQI
21st Jul 20254210 AMAQI
21st Jul 20253711 AMAQI
21st Jul 20253412 PMAQI
21st Jul 2025331 PMAQI
21st Jul 2025332 PMAQI
21st Jul 2025303 PMAQI
21st Jul 2025324 PMAQI
21st Jul 2025385 PMAQI
21st Jul 2025386 PMAQI
21st Jul 2025377 PMAQI
21st Jul 2025368 PMAQI
21st Jul 2025429 PMAQI
21st Jul 20254310 PMAQI
21st Jul 20253611 PMAQI
22nd Jul 20253712 AMAQI
22nd Jul 2025341 AMAQI
22nd Jul 2025312 AMAQI
22nd Jul 2025193 AMAQI
22nd Jul 2025204 AMAQI
22nd Jul 2025195 AMAQI

17°C11/22°C

22nd Jul 2025186 AMAQI
22nd Jul 2025187 AMAQI
22nd Jul 2025188 AMAQI
22nd Jul 2025189 AMAQI
22nd Jul 20251910 AMAQI
22nd Jul 20251811 AMAQI
22nd Jul 20251912 PMAQI
22nd Jul 2025191 PMAQI
22nd Jul 2025222 PMAQI
22nd Jul 2025223 PMAQI
22nd Jul 2025224 PMAQI
22nd Jul 2025225 PMAQI
22nd Jul 2025226 PMAQI
22nd Jul 2025227 PMAQI
22nd Jul 2025228 PMAQI
22nd Jul 2025229 PMAQI
22nd Jul 20252110 PMAQI
22nd Jul 20252311 PMAQI
23rd Jul 20252212 AMAQI
23rd Jul 2025221 AMAQI
23rd Jul 2025212 AMAQI
23rd Jul 2025213 AMAQI
23rd Jul 2025224 AMAQI
23rd Jul 2025225 AMAQI

17°C9/23°C

23rd Jul 2025216 AMAQI
23rd Jul 2025227 AMAQI
23rd Jul 2025228 AMAQI
23rd Jul 2025229 AMAQI
23rd Jul 20252210 AMAQI
23rd Jul 20252211 AMAQI
23rd Jul 20252312 PMAQI
23rd Jul 2025221 PMAQI
23rd Jul 2025232 PMAQI
23rd Jul 2025213 PMAQI
23rd Jul 2025224 PMAQI
23rd Jul 2025235 PMAQI
23rd Jul 2025256 PMAQI
23rd Jul 2025237 PMAQI
23rd Jul 2025248 PMAQI
23rd Jul 2025239 PMAQI
23rd Jul 20252410 PMAQI
23rd Jul 20252511 PMAQI
24th Jul 20252512 AMAQI
24th Jul 2025241 AMAQI
24th Jul 2025242 AMAQI
24th Jul 2025263 AMAQI
24th Jul 2025284 AMAQI
24th Jul 2025285 AMAQI

21°C12/31°C

24th Jul 2025266 AMAQI
24th Jul 2025267 AMAQI
24th Jul 2025288 AMAQI
24th Jul 2025309 AMAQI
24th Jul 20253310 AMAQI
24th Jul 20254011 AMAQI
24th Jul 20254412 PMAQI
24th Jul 2025471 PMAQI
24th Jul 2025502 PMAQI
24th Jul 2025473 PMAQI
24th Jul 2025444 PMAQI
24th Jul 2025435 PMAQI
24th Jul 2025456 PMAQI
24th Jul 2025447 PMAQI
24th Jul 2025428 PMAQI
24th Jul 2025389 PMAQI
24th Jul 20253710 PMAQI
24th Jul 20253611 PMAQI
25th Jul 20253312 AMAQI
25th Jul 2025321 AMAQI
25th Jul 2025312 AMAQI
25th Jul 2025303 AMAQI
25th Jul 2025314 AMAQI
25th Jul 2025335 AMAQI

25°C15/35°C

25th Jul 2025356 AMAQI
25th Jul 2025367 AMAQI
25th Jul 2025388 AMAQI
25th Jul 2025369 AMAQI
25th Jul 20253310 AMAQI
25th Jul 20253211 AMAQI
25th Jul 20253112 PMAQI
25th Jul 2025321 PMAQI
25th Jul 2025322 PMAQI
25th Jul 2025303 PMAQI
25th Jul 2025344 PMAQI
25th Jul 2025385 PMAQI
25th Jul 2025396 PMAQI
25th Jul 2025387 PMAQI
25th Jul 2025408 PMAQI
25th Jul 2025399 PMAQI
25th Jul 20253810 PMAQI
25th Jul 20253911 PMAQI
26th Jul 20253512 AMAQI
26th Jul 2025361 AMAQI
26th Jul 2025572 AMAQI
26th Jul 2025603 AMAQI
26th Jul 2025624 AMAQI
26th Jul 2025645 AMAQI

24°C21/28°C

26th Jul 2025646 AMAQI
26th Jul 2025627 AMAQI
26th Jul 2025598 AMAQI
26th Jul 2025669 AMAQI
26th Jul 20256710 AMAQI
26th Jul 20256811 AMAQI
26th Jul 20256612 PMAQI
26th Jul 2025611 PMAQI
26th Jul 2025602 PMAQI
26th Jul 2025583 PMAQI
26th Jul 2025564 PMAQI
26th Jul 2025575 PMAQI
26th Jul 2025566 PMAQI
26th Jul 2025557 PMAQI
26th Jul 2025548 PMAQI
26th Jul 2025589 PMAQI
26th Jul 20255910 PMAQI
26th Jul 20255211 PMAQI
27th Jul 20255112 AMAQI
27th Jul 2025481 AMAQI
27th Jul 2025362 AMAQI
27th Jul 2025423 AMAQI
27th Jul 2025394 AMAQI
27th Jul 2025385 AMAQI

22°C16/29°C

27th Jul 2025366 AMAQI
27th Jul 2025357 AMAQI
27th Jul 2025368 AMAQI
27th Jul 2025379 AMAQI
27th Jul 20253710 AMAQI
27th Jul 20253811 AMAQI
27th Jul 20254212 PMAQI
27th Jul 2025431 PMAQI
27th Jul 2025402 PMAQI
27th Jul 2025403 PMAQI
27th Jul 2025414 PMAQI
27th Jul 2025445 PMAQI
27th Jul 2025446 PMAQI
27th Jul 2025447 PMAQI
27th Jul 2025448 PMAQI
27th Jul 2025429 PMAQI
27th Jul 20254310 PMAQI
27th Jul 20254911 PMAQI
28th Jul 20254712 AMAQI
28th Jul 2025501 AMAQI
28th Jul 2025522 AMAQI
28th Jul 2025523 AMAQI
28th Jul 2025524 AMAQI
28th Jul 2025505 AMAQI

25°C19/32°C

28th Jul 2025506 AMAQI
28th Jul 2025497 AMAQI
28th Jul 2025478 AMAQI
28th Jul 2025519 AMAQI
28th Jul 20254910 AMAQI
28th Jul 20255511 AMAQI
28th Jul 20255512 PMAQI
28th Jul 2025541 PMAQI
28th Jul 2025532 PMAQI
28th Jul 2025523 PMAQI
28th Jul 2025534 PMAQI
28th Jul 2025525 PMAQI
28th Jul 2025526 PMAQI
28th Jul 2025527 PMAQI
28th Jul 2025528 PMAQI
28th Jul 2025529 PMAQI
28th Jul 20255210 PMAQI
28th Jul 20255011 PMAQI
29th Jul 20255012 AMAQI
29th Jul 2025501 AMAQI
29th Jul 2025482 AMAQI
29th Jul 2025503 AMAQI
29th Jul 2025494 AMAQI
29th Jul 2025475 AMAQI

24°C14/34°C

29th Jul 2025426 AMAQI
29th Jul 2025377 AMAQI
29th Jul 2025378 AMAQI
29th Jul 2025419 AMAQI
29th Jul 20254110 AMAQI
29th Jul 20254211 AMAQI
29th Jul 20253812 PMAQI
29th Jul 2025381 PMAQI
29th Jul 2025362 PMAQI
29th Jul 2025363 PMAQI
29th Jul 2025384 PMAQI
29th Jul 2025425 PMAQI
29th Jul 2025416 PMAQI
29th Jul 2025427 PMAQI
29th Jul 2025408 PMAQI
29th Jul 2025439 PMAQI
29th Jul 20254210 PMAQI
29th Jul 20254011 PMAQI
30th Jul 20254012 AMAQI
30th Jul 2025421 AMAQI
30th Jul 2025432 AMAQI
30th Jul 2025453 AMAQI
30th Jul 2025454 AMAQI
30th Jul 2025445 AMAQI

25°C19/33°C

30th Jul 2025446 AMAQI
30th Jul 2025457 AMAQI
30th Jul 2025458 AMAQI
30th Jul 2025489 AMAQI
30th Jul 20254710 AMAQI
30th Jul 20254611 AMAQI
30th Jul 20254912 PMAQI
30th Jul 2025521 PMAQI
30th Jul 2025532 PMAQI
30th Jul 2025533 PMAQI
30th Jul 2025554 PMAQI
30th Jul 2025555 PMAQI
30th Jul 2025556 PMAQI
30th Jul 2025557 PMAQI
30th Jul 2025558 PMAQI
30th Jul 2025559 PMAQI
30th Jul 20255510 PMAQI
30th Jul 20255211 PMAQI
31st Jul 20255012 AMAQI
31st Jul 2025541 AMAQI
31st Jul 2025602 AMAQI
31st Jul 2025683 AMAQI
31st Jul 2025864 AMAQI
31st Jul 2025805 AMAQI

23°C17/28°C

31st Jul 2025786 AMAQI
31st Jul 2025807 AMAQI
31st Jul 20251068 AMAQI
31st Jul 20251159 AMAQI
31st Jul 202510210 AMAQI
31st Jul 20256711 AMAQI
31st Jul 202510612 PMAQI
31st Jul 20251421 PMAQI
31st Jul 20251522 PMAQI
31st Jul 20251423 PMAQI
31st Jul 20251344 PMAQI
31st Jul 20251205 PMAQI
31st Jul 2025966 PMAQI
31st Jul 2025867 PMAQI
31st Jul 2025928 PMAQI
31st Jul 20251299 PMAQI
31st Jul 202510310 PMAQI
31st Jul 20258811 PMAQI
1st Aug 20258812 AMAQI
1st Aug 2025901 AMAQI
1st Aug 2025882 AMAQI
1st Aug 2025723 AMAQI
1st Aug 2025754 AMAQI
1st Aug 2025715 AMAQI

19°C14/24°C

1st Aug 2025656 AMAQI
1st Aug 2025657 AMAQI
1st Aug 2025648 AMAQI
1st Aug 2025629 AMAQI
1st Aug 20255810 AMAQI
1st Aug 20255211 AMAQI
1st Aug 20254412 PMAQI
1st Aug 2025351 PMAQI
1st Aug 2025372 PMAQI
1st Aug 2025323 PMAQI
1st Aug 2025414 PMAQI
1st Aug 2025285 PMAQI
1st Aug 2025296 PMAQI
1st Aug 2025257 PMAQI
1st Aug 2025308 PMAQI
1st Aug 2025429 PMAQI
1st Aug 20253410 PMAQI
1st Aug 20252311 PMAQI
2nd Aug 20252612 AMAQI
2nd Aug 2025261 AMAQI
2nd Aug 2025262 AMAQI
2nd Aug 2025363 AMAQI
2nd Aug 2025354 AMAQI
2nd Aug 2025325 AMAQI

17°C9/25°C

2nd Aug 2025306 AMAQI
2nd Aug 2025327 AMAQI
2nd Aug 2025328 AMAQI
2nd Aug 2025329 AMAQI
2nd Aug 20253110 AMAQI
2nd Aug 20253311 AMAQI
2nd Aug 20253912 PMAQI
2nd Aug 2025301 PMAQI
2nd Aug 2025312 PMAQI
2nd Aug 2025393 PMAQI
2nd Aug 2025514 PMAQI
2nd Aug 2025615 PMAQI
2nd Aug 2025706 PMAQI
2nd Aug 2025787 PMAQI
2nd Aug 2025808 PMAQI
2nd Aug 2025489 PMAQI
2nd Aug 20256810 PMAQI
2nd Aug 20259711 PMAQI
3rd Aug 20259712 AMAQI
3rd Aug 20251001 AMAQI
3rd Aug 20251052 AMAQI
3rd Aug 20251123 AMAQI
3rd Aug 2025954 AMAQI
3rd Aug 2025645 AMAQI

18°C9/26°C

3rd Aug 2025756 AMAQI
3rd Aug 2025947 AMAQI
3rd Aug 20251128 AMAQI
3rd Aug 20251079 AMAQI
3rd Aug 202510210 AMAQI
3rd Aug 20259211 AMAQI
3rd Aug 202510612 PMAQI
3rd Aug 20251121 PMAQI
3rd Aug 20251152 PMAQI
3rd Aug 20251223 PMAQI
3rd Aug 20251104 PMAQI
3rd Aug 20251145 PMAQI
3rd Aug 20251066 PMAQI
3rd Aug 20251047 PMAQI
3rd Aug 2025868 PMAQI
3rd Aug 20251049 PMAQI
3rd Aug 202512610 PMAQI
3rd Aug 202512211 PMAQI
4th Aug 202512412 AMAQI
4th Aug 20251331 AMAQI
4th Aug 20251262 AMAQI
4th Aug 20251243 AMAQI
4th Aug 20251324 AMAQI
4th Aug 20251245 AMAQI

20°C11/29°C

4th Aug 20251236 AMAQI
4th Aug 20251327 AMAQI
4th Aug 20251278 AMAQI
4th Aug 20251359 AMAQI
4th Aug 202514510 AMAQI
4th Aug 202514711 AMAQI
4th Aug 202514412 PMAQI
4th Aug 20251351 PMAQI
4th Aug 20251232 PMAQI
4th Aug 20251243 PMAQI
4th Aug 20251164 PMAQI
4th Aug 20251205 PMAQI
4th Aug 20251186 PMAQI
4th Aug 20251067 PMAQI
4th Aug 2025978 PMAQI
4th Aug 20251379 PMAQI
4th Aug 202511810 PMAQI
4th Aug 20259811 PMAQI
5th Aug 20259512 AMAQI
5th Aug 20251081 AMAQI
5th Aug 20251122 AMAQI
5th Aug 20251153 AMAQI
5th Aug 20251184 AMAQI
5th Aug 20251145 AMAQI

21°C13/29°C

5th Aug 20251086 AMAQI
5th Aug 20251087 AMAQI
5th Aug 20251078 AMAQI
5th Aug 20251099 AMAQI
5th Aug 202510710 AMAQI
5th Aug 202510411 AMAQI
5th Aug 20259512 PMAQI
5th Aug 2025941 PMAQI
5th Aug 2025932 PMAQI
5th Aug 2025893 PMAQI
5th Aug 2025894 PMAQI
5th Aug 2025855 PMAQI
5th Aug 2025846 PMAQI
5th Aug 2025967 PMAQI
5th Aug 2025958 PMAQI
5th Aug 2025989 PMAQI
5th Aug 20259510 PMAQI
5th Aug 20259111 PMAQI
6th Aug 20259412 AMAQI
6th Aug 2025971 AMAQI
6th Aug 2025942 AMAQI
6th Aug 2025943 AMAQI
6th Aug 2025944 AMAQI
6th Aug 2025905 AMAQI

22°C14/30°C

6th Aug 2025886 AMAQI
6th Aug 2025817 AMAQI
6th Aug 2025848 AMAQI
6th Aug 2025839 AMAQI
6th Aug 20257810 AMAQI
6th Aug 20257011 AMAQI
6th Aug 20256612 PMAQI
6th Aug 2025661 PMAQI
6th Aug 2025662 PMAQI
6th Aug 2025683 PMAQI
6th Aug 2025724 PMAQI
6th Aug 2025785 PMAQI
6th Aug 2025816 PMAQI
6th Aug 2025777 PMAQI
6th Aug 2025768 PMAQI
6th Aug 2025859 PMAQI
6th Aug 20258010 PMAQI
6th Aug 20257611 PMAQI
7th Aug 20257612 AMAQI
7th Aug 2025731 AMAQI
7th Aug 2025782 AMAQI
7th Aug 2025963 AMAQI
7th Aug 2025964 AMAQI
7th Aug 2025995 AMAQI

22°C17/31°C

7th Aug 2025946 AMAQI
7th Aug 2025907 AMAQI
7th Aug 2025958 AMAQI
7th Aug 2025929 AMAQI
7th Aug 20258810 AMAQI
7th Aug 20259011 AMAQI
7th Aug 20258712 PMAQI
7th Aug 2025851 PMAQI
7th Aug 2025822 PMAQI
7th Aug 2025783 PMAQI
7th Aug 2025814 PMAQI
7th Aug 2025805 PMAQI
7th Aug 2025806 PMAQI
7th Aug 2025817 PMAQI
7th Aug 2025818 PMAQI
7th Aug 2025829 PMAQI
7th Aug 20258610 PMAQI
7th Aug 20258311 PMAQI
8th Aug 20258612 AMAQI
8th Aug 2025821 AMAQI
8th Aug 2025822 AMAQI
8th Aug 2025843 AMAQI
8th Aug 2025854 AMAQI
8th Aug 2025855 AMAQI

23°C18/30°C

8th Aug 2025866 AMAQI
8th Aug 2025887 AMAQI
8th Aug 2025928 AMAQI
8th Aug 2025889 AMAQI
8th Aug 20259110 AMAQI
8th Aug 20258911 AMAQI
8th Aug 20258512 PMAQI
8th Aug 2025831 PMAQI
8th Aug 2025762 PMAQI
8th Aug 2025763 PMAQI
8th Aug 2025734 PMAQI
8th Aug 2025785 PMAQI
8th Aug 2025776 PMAQI
8th Aug 2025757 PMAQI
8th Aug 2025748 PMAQI
8th Aug 2025809 PMAQI
8th Aug 20258310 PMAQI
8th Aug 20257311 PMAQI
9th Aug 20257412 AMAQI
9th Aug 2025701 AMAQI
9th Aug 2025562 AMAQI
9th Aug 2025543 AMAQI
9th Aug 2025544 AMAQI
9th Aug 2025545 AMAQI

22°C16/28°C

9th Aug 2025546 AMAQI
9th Aug 2025567 AMAQI
9th Aug 2025578 AMAQI
9th Aug 2025609 AMAQI
9th Aug 20256010 AMAQI
9th Aug 20256211 AMAQI
9th Aug 20256012 PMAQI
9th Aug 2025581 PMAQI
9th Aug 2025572 PMAQI
9th Aug 2025553 PMAQI
9th Aug 2025564 PMAQI
9th Aug 2025595 PMAQI
9th Aug 2025606 PMAQI
9th Aug 2025597 PMAQI
9th Aug 2025588 PMAQI
9th Aug 2025589 PMAQI
9th Aug 20255910 PMAQI
9th Aug 20256011 PMAQI
10th Aug 20256012 AMAQI
10th Aug 2025601 AMAQI
10th Aug 2025612 AMAQI
10th Aug 2025613 AMAQI
10th Aug 2025624 AMAQI
10th Aug 2025635 AMAQI

24°C17/30°C

10th Aug 2025646 AMAQI
10th Aug 2025647 AMAQI
10th Aug 2025648 AMAQI
10th Aug 2025649 AMAQI
10th Aug 20256410 AMAQI
10th Aug 20256411 AMAQI
10th Aug 20256412 PMAQI
10th Aug 2025631 PMAQI
10th Aug 2025622 PMAQI
10th Aug 2025623 PMAQI
10th Aug 2025624 PMAQI
10th Aug 2025645 PMAQI
10th Aug 2025626 PMAQI
10th Aug 2025607 PMAQI
10th Aug 2025618 PMAQI
10th Aug 2025629 PMAQI
10th Aug 20256310 PMAQI
10th Aug 20256211 PMAQI
11th Aug 20256212 AMAQI
11th Aug 2025621 AMAQI
11th Aug 2025622 AMAQI
11th Aug 2025623 AMAQI
11th Aug 2025614 AMAQI
11th Aug 2025615 AMAQI

25°C18/33°C

11th Aug 2025606 AMAQI
11th Aug 2025607 AMAQI
11th Aug 2025628 AMAQI
11th Aug 2025629 AMAQI
11th Aug 20256210 AMAQI
11th Aug 20256611 AMAQI
11th Aug 20256212 PMAQI
11th Aug 2025641 PMAQI
11th Aug 2025642 PMAQI
11th Aug 2025613 PMAQI
11th Aug 2025604 PMAQI
11th Aug 2025595 PMAQI
11th Aug 2025636 PMAQI
11th Aug 2025627 PMAQI
11th Aug 2025628 PMAQI
11th Aug 2025629 PMAQI
11th Aug 20256010 PMAQI
11th Aug 20255711 PMAQI
12th Aug 20255512 AMAQI
12th Aug 2025551 AMAQI
12th Aug 2025562 AMAQI
12th Aug 2025563 AMAQI
12th Aug 2025574 AMAQI
12th Aug 2025585 AMAQI

26°C19/33°C

12th Aug 2025596 AMAQI
12th Aug 2025607 AMAQI
12th Aug 2025588 AMAQI
12th Aug 2025609 AMAQI
12th Aug 20256110 AMAQI
12th Aug 20256011 AMAQI
12th Aug 20255812 PMAQI
12th Aug 2025561 PMAQI
12th Aug 2025542 PMAQI
12th Aug 2025533 PMAQI
12th Aug 2025524 PMAQI
12th Aug 2025545 PMAQI
12th Aug 2025526 PMAQI
12th Aug 2025507 PMAQI
12th Aug 2025458 PMAQI
12th Aug 2025569 PMAQI
12th Aug 20254610 PMAQI
12th Aug 20254111 PMAQI
13th Aug 20254312 AMAQI
13th Aug 2025501 AMAQI
13th Aug 2025452 AMAQI
13th Aug 2025433 AMAQI
13th Aug 2025364 AMAQI
13th Aug 2025325 AMAQI

25°C19/31°C

13th Aug 2025356 AMAQI
13th Aug 2025367 AMAQI
13th Aug 2025368 AMAQI
13th Aug 2025369 AMAQI
13th Aug 20253310 AMAQI
13th Aug 20253611 AMAQI
13th Aug 20253612 PMAQI
13th Aug 2025391 PMAQI
13th Aug 2025422 PMAQI
13th Aug 2025513 PMAQI
13th Aug 2025564 PMAQI
13th Aug 2025595 PMAQI
13th Aug 2025616 PMAQI
13th Aug 2025617 PMAQI
13th Aug 2025638 PMAQI
13th Aug 2025409 PMAQI
13th Aug 20254710 PMAQI
13th Aug 20255411 PMAQI
14th Aug 20255512 AMAQI
14th Aug 2025551 AMAQI
14th Aug 2025542 AMAQI
14th Aug 2025573 AMAQI
14th Aug 2025564 AMAQI
14th Aug 2025585 AMAQI

23°C18/28°C

14th Aug 2025606 AMAQI
14th Aug 2025607 AMAQI
14th Aug 2025628 AMAQI
14th Aug 2025679 AMAQI
14th Aug 20256610 AMAQI
14th Aug 20255111 AMAQI
14th Aug 20253912 PMAQI
14th Aug 2025471 PMAQI
14th Aug 2025602 PMAQI
14th Aug 2025593 PMAQI
14th Aug 2025614 PMAQI
14th Aug 2025605 PMAQI
14th Aug 2025626 PMAQI
14th Aug 2025597 PMAQI
14th Aug 2025608 PMAQI
14th Aug 2025629 PMAQI
14th Aug 20256010 PMAQI
14th Aug 20256311 PMAQI
15th Aug 20256412 AMAQI
15th Aug 2025641 AMAQI
15th Aug 2025652 AMAQI
15th Aug 2025683 AMAQI
15th Aug 2025744 AMAQI
15th Aug 2025725 AMAQI

21°C12/28°C

15th Aug 2025716 AMAQI
15th Aug 2025727 AMAQI
15th Aug 2025708 AMAQI
15th Aug 2025749 AMAQI
15th Aug 20257610 AMAQI
15th Aug 20257511 AMAQI
15th Aug 20256712 PMAQI
15th Aug 2025641 PMAQI
15th Aug 2025662 PMAQI
15th Aug 2025643 PMAQI
15th Aug 2025624 PMAQI
15th Aug 2025625 PMAQI
15th Aug 2025636 PMAQI
15th Aug 2025617 PMAQI
15th Aug 2025658 PMAQI
15th Aug 2025699 PMAQI
15th Aug 20256210 PMAQI
15th Aug 20256011 PMAQI
16th Aug 20255812 AMAQI
16th Aug 2025591 AMAQI
16th Aug 2025582 AMAQI
16th Aug 2025583 AMAQI
16th Aug 2025604 AMAQI
16th Aug 2025605 AMAQI

23°C16/31°C

16th Aug 2025606 AMAQI
16th Aug 2025607 AMAQI
16th Aug 2025578 AMAQI
16th Aug 2025599 AMAQI
16th Aug 20256010 AMAQI
16th Aug 20256211 AMAQI
16th Aug 20256212 PMAQI
16th Aug 2025631 PMAQI
16th Aug 2025642 PMAQI
16th Aug 2025643 PMAQI
16th Aug 2025634 PMAQI
16th Aug 2025625 PMAQI
16th Aug 2025626 PMAQI
16th Aug 2025617 PMAQI
16th Aug 2025608 PMAQI
16th Aug 2025599 PMAQI
16th Aug 20255810 PMAQI
16th Aug 20255811 PMAQI
17th Aug 20255912 AMAQI
17th Aug 2025601 AMAQI
17th Aug 2025622 AMAQI
17th Aug 2025613 AMAQI
17th Aug 2025594 AMAQI
17th Aug 2025605 AMAQI

25°C17/33°C

17th Aug 2025566 AMAQI
17th Aug 2025507 AMAQI
17th Aug 2025448 AMAQI
17th Aug 2025349 AMAQI
17th Aug 20253110 AMAQI
17th Aug 20252811 AMAQI
17th Aug 20252812 PMAQI
17th Aug 2025251 PMAQI
17th Aug 2025262 PMAQI
17th Aug 2025223 PMAQI
17th Aug 2025224 PMAQI
17th Aug 2025215 PMAQI
17th Aug 2025196 PMAQI
17th Aug 2025217 PMAQI
17th Aug 2025188 PMAQI
17th Aug 2025309 PMAQI
17th Aug 20252410 PMAQI
17th Aug 20251611 PMAQI
18th Aug 20251612 AMAQI
18th Aug 2025161 AMAQI
18th Aug 2025152 AMAQI
18th Aug 2025153 AMAQI
18th Aug 2025144 AMAQI
18th Aug 2025135 AMAQI

21°C14/25°C

18th Aug 2025146 AMAQI
18th Aug 2025147 AMAQI
18th Aug 2025148 AMAQI
18th Aug 2025159 AMAQI
18th Aug 20251510 AMAQI
18th Aug 20251511 AMAQI
18th Aug 20251512 PMAQI
18th Aug 2025161 PMAQI
18th Aug 2025152 PMAQI
18th Aug 2025163 PMAQI
18th Aug 2025144 PMAQI
18th Aug 2025165 PMAQI
18th Aug 2025166 PMAQI
18th Aug 2025147 PMAQI
18th Aug 2025148 PMAQI
18th Aug 2025169 PMAQI
18th Aug 20251610 PMAQI
18th Aug 20251711 PMAQI
19th Aug 20251712 AMAQI
19th Aug 2025181 AMAQI
19th Aug 2025182 AMAQI
19th Aug 2025183 AMAQI
19th Aug 2025184 AMAQI
19th Aug 2025175 AMAQI

16°C9/24°C

19th Aug 2025176 AMAQI
19th Aug 2025187 AMAQI
19th Aug 2025188 AMAQI
19th Aug 2025179 AMAQI
19th Aug 20251810 AMAQI
19th Aug 20251811 AMAQI
19th Aug 20251812 PMAQI
19th Aug 2025181 PMAQI
19th Aug 2025202 PMAQI
19th Aug 2025223 PMAQI
19th Aug 2025244 PMAQI
19th Aug 2025255 PMAQI
19th Aug 2025276 PMAQI
19th Aug 2025317 PMAQI
19th Aug 2025328 PMAQI
19th Aug 2025189 PMAQI
19th Aug 20252510 PMAQI
19th Aug 20252911 PMAQI
20th Aug 20252812 AMAQI
20th Aug 2025241 AMAQI
20th Aug 2025212 AMAQI
20th Aug 2025183 AMAQI
20th Aug 2025184 AMAQI
20th Aug 2025185 AMAQI

18°C12/24°C

20th Aug 2025176 AMAQI
6 AM
20th Aug 2025167 AMAQI
20th Aug 2025158 AMAQI
20th Aug 2025169 AMAQI
20th Aug 20251710 AMAQI
20th Aug 20251711 AMAQI
20th Aug 20251612 PMAQI
20th Aug 2025161 PMAQI
1 PM
20th Aug 2025162 PMAQI
20th Aug 2025163 PMAQI
20th Aug 2025164 PMAQI
20th Aug 2025155 PMAQI
20th Aug 2025166 PMAQI
20th Aug 2025177 PMAQI
8 PM
1 AM
5 AM

--°C/°C

Day time
Avg. Highest Time
6 AM - 8 PM

56AQI

15 hours / Day
450 hours / Month
Avg. Lowest Time
6 AM - 8 PM

56AQI

15 hours / Day
450 hours / Month
In the last 30 days, during the daytime, the highest AQI was between 6 AM to 8 PM (Avg. 56), while the lowest AQI was between 6 AM to 8 PM (Avg. 56).
Night time
Avg. Highest Time
12 AM - 11 PM

57AQI

9 hours / Day
270 hours / Month
Avg. Lowest Time
12 AM - 11 PM

57AQI

9 hours / Day
270 hours / Month
In the last 30 days, during the daytime, the highest AQI was between 12 AM to 11 PM (Avg. 57), while the lowest AQI was between 12 AM to 11 PM (Avg. 57).

2025 Days Vs Air Quality

Guelph, Ontario, Canada

2025

84%

193

16%

36

0.8%

2

Total number of days with different AQI categories in last 232 days in 2025 (133 days remaining)

Good
193 Days
Moderate
36 Days
Poor
2 Days
Unhealthy
0 Days
Severe
0 Days
Hazardous
0 Days

Under WHO’s Safe Air Quality Limits: 84%

Health Risk Level:

Low

In 2025, 84% of 232 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

Guelph, Ontario, Canada

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.

1st January 2025
21AQI
2nd January 2025
21AQI
3rd January 2025
23AQI
4th January 2025
28AQI
5th January 2025
27AQI
6th January 2025
23AQI
7th January 2025
24AQI
8th January 2025
28AQI
9th January 2025
29AQI
10th January 2025
45AQI
11th January 2025
62AQI
12th January 2025
45AQI
13th January 2025
36AQI
14th January 2025
26AQI
15th January 2025
24AQI
16th January 2025
49AQI
17th January 2025
37AQI
18th January 2025
30AQI
19th January 2025
26AQI
20th January 2025
25AQI
21st January 2025
24AQI
22nd January 2025
30AQI
23rd January 2025
41AQI
24th January 2025
26AQI
25th January 2025
48AQI
26th January 2025
31AQI
27th January 2025
27AQI
28th January 2025
29AQI
29th January 2025
28AQI
30th January 2025
25AQI
31st January 2025
53AQI
1st February 2025
27AQI
2nd February 2025
28AQI
3rd February 2025
55AQI
4th February 2025
27AQI
5th February 2025
25AQI
6th February 2025
33AQI
7th February 2025
28AQI
8th February 2025
37AQI
9th February 2025
32AQI
10th February 2025
29AQI
11th February 2025
40AQI
12th February 2025
27AQI
13th February 2025
26AQI
14th February 2025
30AQI
15th February 2025
33AQI
16th February 2025
28AQI
17th February 2025
28AQI
18th February 2025
27AQI
19th February 2025
25AQI
20th February 2025
22AQI
21st February 2025
28AQI
22nd February 2025
49AQI
23rd February 2025
59AQI
24th February 2025
54AQI
25th February 2025
61AQI
26th February 2025
32AQI
27th February 2025
38AQI
28th February 2025
26AQI
1st March 2025
30AQI
2nd March 2025
28AQI
3rd March 2025
31AQI
4th March 2025
36AQI
5th March 2025
37AQI
6th March 2025
27AQI
7th March 2025
32AQI
8th March 2025
32AQI
9th March 2025
30AQI
10th March 2025
32AQI
11th March 2025
31AQI
12th March 2025
26AQI
13th March 2025
29AQI
14th March 2025
54AQI
15th March 2025
56AQI
16th March 2025
26AQI
17th March 2025
15AQI
18th March 2025
24AQI
19th March 2025
31AQI
20th March 2025
24AQI
21st March 2025
17AQI
22nd March 2025
17AQI
23rd March 2025
19AQI
24th March 2025
20AQI
25th March 2025
18AQI
26th March 2025
19AQI
27th March 2025
27AQI
28th March 2025
24AQI
29th March 2025
30AQI
30th March 2025
22AQI
31st March 2025
21AQI
1st April 2025
16AQI
2nd April 2025
17AQI
3rd April 2025
22AQI
4th April 2025
17AQI
5th April 2025
19AQI
6th April 2025
16AQI
7th April 2025
19AQI
8th April 2025
14AQI
9th April 2025
19AQI
10th April 2025
34AQI
11th April 2025
27AQI
12th April 2025
23AQI
13th April 2025
36AQI
14th April 2025
27AQI
15th April 2025
17AQI
16th April 2025
13AQI
17th April 2025
19AQI
18th April 2025
33AQI
19th April 2025
41AQI
20th April 2025
16AQI
21st April 2025
20AQI
22nd April 2025
14AQI
23rd April 2025
26AQI
24th April 2025
37AQI
25th April 2025
30AQI
26th April 2025
27AQI
27th April 2025
14AQI
28th April 2025
22AQI
29th April 2025
32AQI
30th April 2025
17AQI
1st May 2025
34AQI
2nd May 2025
28AQI
3rd May 2025
18AQI
4th May 2025
16AQI
5th May 2025
18AQI
6th May 2025
19AQI
7th May 2025
38AQI
8th May 2025
18AQI
9th May 2025
21AQI
10th May 2025
27AQI
11th May 2025
23AQI
12th May 2025
27AQI
13th May 2025
33AQI
14th May 2025
21AQI
15th May 2025
32AQI
16th May 2025
29AQI
17th May 2025
27AQI
18th May 2025
19AQI
19th May 2025
14AQI
20th May 2025
14AQI
21st May 2025
15AQI
22nd May 2025
12AQI
23rd May 2025
11AQI
24th May 2025
13AQI
25th May 2025
15AQI
26th May 2025
18AQI
27th May 2025
24AQI
28th May 2025
23AQI
29th May 2025
26AQI
30th May 2025
33AQI
31st May 2025
24AQI
1st June 2025
18AQI
2nd June 2025
23AQI
3rd June 2025
39AQI
4th June 2025
72AQI
5th June 2025
54AQI
6th June 2025
64AQI
7th June 2025
64AQI
8th June 2025
80AQI
9th June 2025
69AQI
10th June 2025
55AQI
11th June 2025
61AQI
12th June 2025
66AQI
13th June 2025
44AQI
14th June 2025
34AQI
15th June 2025
37AQI
16th June 2025
37AQI
17th June 2025
39AQI
18th June 2025
39AQI
19th June 2025
30AQI
20th June 2025
39AQI
21st June 2025
48AQI
22nd June 2025
49AQI
23rd June 2025
53AQI
24th June 2025
54AQI
25th June 2025
43AQI
26th June 2025
40AQI
27th June 2025
37AQI
28th June 2025
32AQI
29th June 2025
35AQI
30th June 2025
39AQI
1st July 2025
38AQI
2nd July 2025
38AQI
3rd July 2025
47AQI
4th July 2025
38AQI
5th July 2025
43AQI
6th July 2025
50AQI
7th July 2025
47AQI
8th July 2025
33AQI
9th July 2025
39AQI
10th July 2025
37AQI
11th July 2025
46AQI
12th July 2025
45AQI
13th July 2025
45AQI
14th July 2025
46AQI
15th July 2025
58AQI
16th July 2025
66AQI
17th July 2025
46AQI
18th July 2025
25AQI
19th July 2025
31AQI
20th July 2025
24AQI
21st July 2025
42AQI
22nd July 2025
23AQI
23rd July 2025
22AQI
24th July 2025
35AQI
25th July 2025
35AQI
26th July 2025
55AQI
27th July 2025
42AQI
28th July 2025
51AQI
29th July 2025
43AQI
30th July 2025
48AQI
31st July 2025
91AQI
1st August 2025
54AQI
2nd August 2025
44AQI
3rd August 2025
103AQI
4th August 2025
124AQI
5th August 2025
100AQI
6th August 2025
83AQI
7th August 2025
85AQI
8th August 2025
82AQI
9th August 2025
60AQI
10th August 2025
62AQI
11th August 2025
61AQI
12th August 2025
54AQI
13th August 2025
45AQI
14th August 2025
58AQI
15th August 2025
67AQI
16th August 2025
60AQI
17th August 2025
39AQI
18th August 2025
15AQI
19th August 2025
20AQI

32AQI

34AQI

28AQI

23AQI

22AQI

46AQI

43AQI

64AQI

No. of days

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

202535AQI

29
2
24
4
29
2
30
31
19
11
26
5
5
12
2
193
36
2

Highest AQI recorded in

August

64AQI

Lowest AQI recorded in

May

22AQI

202432AQI

26
5
26
3
31
30
31
28
30
1
24
7
27
3
29
2
30
30
1
342
22

Highest AQI recorded in

January

37AQI

Lowest AQI recorded in

November

25AQI

202341AQI

26
5
23
5
28
3
24
6
29
2
10
15
5
21
10
21
10
29
1
28
3
26
3
25
6
290
69
5

Highest AQI recorded in

June

68AQI

Lowest AQI recorded in

October

31AQI

202235AQI

29
2
20
1
26
5
30
31
26
4
22
2
1
27
1
28
3
20
10
27
4
287
32

Highest AQI recorded in

November

43AQI

Lowest AQI recorded in

August

19AQI

202136AQI

23
7
25
3
26
5
27
3
23
6
25
5
24
7
26
5
27
2
1
29
2
26
4
27
4
308
53
1

Highest AQI recorded in

July

40AQI

Lowest AQI recorded in

October

30AQI

202033AQI

11
2
21
18
26
4
29
2
29
2
26
4
30
1
26
4
24
7
240
26

Highest AQI recorded in

November

37AQI

Lowest AQI recorded in

October

26AQI

Most & Least Polluted Years Over the Last 6 Years

Most Polluted Year Recorded
2023(Avg.)
41AQI
Least Polluted Year Recorded
2024(Avg.)
32AQI

Guelph's annual 2025 AQI (35) shows an average percentage change of 0.005% (worsened AQI) compared to previous years: 2020 (33), 2021 (36), 2022 (35), 2023 (41), 2024 (32).