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Illinois Ozone Highs

1-Hr/8-Hr High Concentrations
(Values in Parts Per Billion)
First number in each column is 1-hour concentration - Standard of 125 parts per billion
Second number in each column is 8-hour concentration. - Standard of 70 parts per billion;
Region  County Site 9/19  9/20  9/21  9/22  9/23  9/24  9/25 
Chicago Metropolitan  Cook Alsip --/--  44/42  36/36  65/54  45/43  47/41  55/49 
Cook Chicago - ComEd 49/46  47/45  42/35  65/56  43/38  43/38  54/48 
Cook Chicago - SWFP 48/45  50/48  54/44  72/65  58/43  42/40  58/51 
Cook Chicago - Taft 53/47  46/43  41/32  65/53  37/31  40/36  60/52 
Cook Cicero 51/44  42/40  36/30  61/52  37/31  37/32  55/47 
Cook Des Plaines 52/45  47/45  38/29  57/43  36/31  41/36  60/52 
Cook Evanston 57/49  48/46  40/40  70/65  47/34  43/40  60/52 
Cook Lemont 63/58  60/57  42/36  75/61  41/38  59/48  60/50 
Cook Northbrook 54/47  45/43  40/32  57/44  35/28  38/34  62/52 
Cook Schiller Park 43/37  36/34  30/21  54/36  32/27  34/30  55/47 
DuPage Lisle 50/45  49/47  35/29  58/41  38/34  47/37  57/48 
Kane Elgin 53/46  52/47  38/26  61/47  39/34  38/34  57/46 
Lake Zion 53/48  46/42  35/28  40/32  38/28  37/34  58/46 
McHenry Cary 52/45  49/45  38/28  55/44  37/32  37/33  56/45 
Will Braidwood 56/49  66/61  43/40  62/58  66/55  58/46  58/49 
Metro East  Jersey Jerseyville 67/57  69/54  83/71  83/74  76/62  78/70  45/43 
Madison Alton 61/51  75/58  73/67  90/72  83/71  74/67  54/45 
Madison Maryville 52/46  55/49  70/67  73/65  72/66  71/65  68/53 
Madison Wood River 63/50  73/58  71/64  91/70  79/64  73/66  57/46 
Randolph Houston 44/39  44/40  69/63  61/54  64/58  60/55  56/50 
St. Clair East St. Louis 60/48  57/46  70/61  68/60  74/66  62/57  54/43 
Northern Illinois  Rock Island Rock Island 46/44  59/55  49/44  51/44  43/37  41/39  42/35 
Winnebago Loves Park 49/44  54/50  38/32  48/39  39/32  38/33  46/39 
West Central Illinois  Adams Quincy 45/42  53/46  68/57  56/52  60/54  51/48  41/35 
Macoupin Nilwood 63/50  52/47  69/63  75/67  51/48  64/58  56/45 
Peoria Peoria 44/39  57/49  50/46  65/57  66/59  69/55  51/44 
Peoria Peoria Heights 48/43  56/50  52/47  69/61  68/60  56/49  51/44 
Sangamon Springfield 52/49  55/50  70/65  75/69  65/56  71/63  53/46 
East Central Illinois  Champaign Thomasboro 52/46  51/47  69/60  63/60  66/63  54/47  59/51 
McLean Normal 59/51  48/46  64/53  68/65  61/56  67/57  54/45 
Macon Decatur 53/49  48/44  73/68  59/56  68/59  74/62  57/50 
Southeast Illinois  Effingham Effingham 47/42  46/40  77/66  60/56  64/58  57/55  62/51 
Hamilton Knight Prairie Township 42/40  51/49  71/63  60/58  61/32  65/58  67/62