| Station | Location | O3 |
|---|---|---|
| Barrie | 83 Perry St. | N/A |
| Belleville | 2 Sidney St., Water Treatment Plant | 43 |
| Brampton | 109 Mclaughlin Rd. S. | 40 |
| Brantford | 324 Grand River Ave. | 34 |
| Burlington | North Shore Blvd. E./Lakeshore Rd. | N/A |
| Chatham | 435 Grand Ave. W. | 41 |
| Cornwall | Bedford St./3rd St. W. | 40 |
| Dorset | 1026 Bellwood Acres Rd. | N/A |
| Grand Bend | Point Blake Conservation Area | 40 |
| Guelph | Exhibition St./Clark St. W. | 39 |
| Hamilton Downtown | Elgin St./Kelly St. | N/A |
| Hamilton Mountain | 250 Fennell Ave. W. | 38 |
| Hamilton West | Main St. W./Hwy 403 | 37 |
| Kingston | 23 Beechgrove Lane | 38 |
| Kitchener | West Ave./Homewood Ave. | 38 |
| London | 42 St. Julien St. | 38 |
| Milton | 1120 Main St. E. | 41 |
| Mississauga | 3359 Mississauga Rd. N., U of T Campus | 41 |
| Newmarket | Eagle St. W./McCaffrey Rd. | 41 |
| North Bay | Chippewa St. W., Dept. National Defence | 40 |
| Oakville | Eighth Line/Glenashton Dr., Halton Res. | 40 |
| Oshawa | Brittania Ave. W., EP Taylor Stables | 43 |
| Ottawa Downtown | Rideau St./Wurtemburg St. | 37 |
| Parry Sound | 7 Bay St. | 45 |
| Peterborough | 10 Hospital Dr. | 44 |
| Port Stanley | 43665 Dexter Line, Elgin Water T. Plt | 47 |
| Sarnia | 700 Christina St. N. | 43 |
| Sault Ste. Marie | Sault College | 44 |
| St. Catharines | Argyle Cres., Pump Stn. | 35 |
| Sudbury | Applegrove St./Birch St. | 39 |
| Thunder Bay | 615 James St. S., MTO | 34 |
| Tiverton | 4th Concession/Bruce Rd. 23 | 42 |
| Toronto Downtown | 55 John St. | 32 |
| Toronto East | Kennedy Rd./Lawrence Ave. E. | 40 |
| Toronto North | 4905 Dufferin St., Eccc | 39 |
| Toronto West | 125 Resources Rd. | 40 |
| Windsor Downtown | 467 University Ave. W. | 46 |
| Windsor West | College Ave./South St. | 45 |
ozone O3 Concentrations for Sunday, March 15, 2026, 4:00 pm
Note: The pollutant concentrations on this web page are based on automatically polled data and have not undergone final verification.
Note: N/A (not available) denotes invalid or missing data.
Ontario 1-hour AAQC for O3 = 80 ppb