2002 Ozone Season Data & Summary
Color-coded review of daily peak 8-hour-averaged ozone concentrations at all Massachusetts state ozone monitors.
This page lists the 2002 season daily peak 8-hour-averaged ozone concentrations, colored according to Air Quality Index categories (see explanation of colors), at all Massachusetts state ozone monitors. Values shown are preliminary. Quality assurance checks may, for a small number of values, result in slight changes or invalidation. PPB refers to ozone concentration in parts of ozone per billion parts of air. "M" denotes missing data. See the summary below.
May 2002 Peak 8-HR Ozone Concentration (PPB) at MA Monitors

| Date |
Adams |
Aga- wam |
Am- herst |
Blue Hill |
Chic- opee |
Fair- haven |
Law- rence |
L. Island |
Lynn |
New- bury |
Rox- bury |
Stow |
Truro |
Ware |
Wor- cester |
| 5/1 |
39 |
41 |
38 |
48 |
39 |
42 |
37 |
42 |
43 |
43 |
29 |
47 |
48 |
43 |
46 |
| 5/2 |
48 |
37 |
39 |
50 |
37 |
51 |
39 |
50 |
44 |
53 |
23 |
39 |
55 |
48 |
44 |
| 5/3 |
22 |
43 |
40 |
47 |
40 |
45 |
39 |
43 |
43 |
42 |
32 |
43 |
48 |
41 |
46 |
| 5/4 |
40 |
53 |
54 |
61 |
52 |
47 |
46 |
50 |
51 |
52 |
39 |
55 |
55 |
56 |
60 |
| 5/5 |
46 |
48 |
61 |
72 |
59 |
60 |
57 |
58 |
53 |
59 |
54 |
65 |
58 |
64 |
70 |
|
5/6 |
55 |
68 |
65 |
75 |
67 |
57 |
68 |
66 |
60 |
68 |
52 |
75 |
62 |
70 |
78 |
| 5/7 |
42 |
54 |
51 |
60 |
55 |
48 |
51 |
55 |
51 |
55 |
42 |
63 |
52 |
57 |
65 |
| 5/8 |
38 |
41 |
43 |
44 |
49 |
39 |
37 |
43 |
39 |
44 |
33 |
41 |
42 |
49 |
48 |
| 5/9 |
35 |
31 |
32 |
39 |
35 |
40 |
28 |
40 |
34 |
43 |
21 |
27 |
43 |
36 |
33 |
| 5/10 |
29 |
61 |
60 |
68 |
63 |
53 |
55 |
55 |
61 |
61 |
46 |
61 |
61 |
60 |
49 |
| 5/11 |
43 |
58 |
49 |
57 |
58 |
55 |
42 |
47 |
48 |
46 |
40 |
50 |
55 |
51 |
40 |
| 5/12 |
45 |
36 |
37 |
62 |
45 |
55 |
42 |
60 |
52 |
55 |
53 |
47 |
63 |
45 |
38 |
| 5/13 |
45 |
41 |
43 |
60 |
49 |
53 |
46 |
59 |
49 |
56 |
43 |
48 |
60 |
47 |
42 |
| 5/14 |
36 |
45 |
38 |
48 |
46 |
51 |
39 |
43 |
44 |
48 |
32 |
43 |
53 |
44 |
37 |
| 5/15 |
27 |
50 |
48 |
48 |
47 |
45 |
39 |
41 |
42 |
42 |
29 |
43 |
45 |
47 |
38 |
| 5/16 |
31 |
63 |
58 |
69 |
60 |
78 |
48 |
60 |
53 |
63 |
46 |
63 |
82 |
60 |
52 |
| 5/17 |
24 |
49 |
45 |
55 |
51 |
61 |
37 |
42 |
48 |
51 |
37 |
47 |
67 |
48 |
41 |
| 5/18 |
31 |
33 |
32 |
42 |
37 |
38 |
30 |
39 |
36 |
41 |
26 |
32 |
40 |
36 |
31 |
| 5/19 |
32 |
43 |
41 |
51 |
46 |
47 |
40 |
43 |
46 |
43 |
40 |
44 |
48 |
42 |
34 |
| 5/20 |
30 |
45 |
41 |
47 |
46 |
45 |
36 |
37 |
39 |
41 |
31 |
43 |
41 |
44 |
33 |
| 5/21 |
19 |
37 |
34 |
40 |
39 |
38 |
29 |
31 |
35 |
34 |
22 |
35 |
37 |
36 |
28 |
| 5/22 |
20 |
50 |
50 |
58 |
54 |
47 |
43 |
48 |
48 |
47 |
40 |
52 |
50 |
51 |
37 |
| 5/23 |
51 |
58 |
56 |
68 |
59 |
56 |
53 |
59 |
57 |
59 |
48 |
64 |
63 |
59 |
52 |
| 5/24 |
31 |
73 |
70 |
88 |
79 |
71 |
65 |
69 |
76 |
75 |
57 |
78 |
84 |
75 |
65 |
| 5/25 |
39 |
48 |
46 |
46 |
51 |
37 |
31 |
36 |
35 |
36 |
32 |
44 |
36 |
46 |
40 |
| 5/26 |
37 |
33 |
31 |
46 |
35 |
37 |
32 |
43 |
39 |
40 |
36 |
44 |
43 |
36 |
30 |
| 5/27 |
46 |
53 |
59 |
59 |
60 |
50 |
42 |
39 |
45 |
39 |
34 |
49 |
52 |
59 |
40 |
| 5/28 |
41 |
28 |
30 |
31 |
31 |
44 |
24 |
35 |
26 |
42 |
15 |
26 |
39 |
46 |
37 |
| 5/29 |
34 |
36 |
39 |
39 |
44 |
36 |
20 |
30 |
28 |
37 |
16 |
29 |
32 |
45 |
32 |
| 5/30 |
48 |
46 |
47 |
38 |
50 |
28 |
43 |
35 |
37 |
42 |
23 |
46 |
24 |
51 |
41 |
| 5/31 |
56 |
42 |
41 |
46 |
45 |
46 |
47 |
39 |
46 |
51 |
38 |
46 |
42 |
51 |
40 |
June 2002 Peak 8-HR Ozone Concentration (PPB) at MA Monitors

| Date |
Adams |
Aga- wam |
Am- herst |
Blue Hill |
Chic- opee |
Fair- haven |
Law- rence |
L. Island |
Lynn |
New- bury |
Rox- bury |
Stow |
Truro |
Ware |
Wor- cester |
| 6/1 |
58 |
59 |
60 |
67 |
62 |
75 |
54 |
56 |
64 |
60 |
47 |
62 |
73 |
61 |
54 |
| 6/2 |
56 |
49 |
47 |
60 |
53 |
50 |
49 |
51 |
60 |
56 |
49 |
51 |
54 |
53 |
45 |
| 6/3 |
37 |
44 |
40 |
49 |
46 |
48 |
40 |
49 |
49 |
46 |
34 |
41 |
46 |
43 |
33 |
| 6/4 |
47 |
47 |
54 |
58 |
59 |
47 |
37 |
47 |
43 |
44 |
45 |
50 |
49 |
M |
47 |
| 6/5 |
57 |
47 |
45 |
52 |
49 |
52 |
40 |
44 |
43 |
47 |
40 |
52 |
50 |
44 |
43 |
|
6/6 |
44 |
24 |
25 |
36 |
32 |
39 |
26 |
32 |
30 |
36 |
27 |
36 |
36 |
31 |
M |
| 6/7 |
30 |
33 |
32 |
36 |
39 |
36 |
26 |
34 |
35 |
38 |
15 |
30 |
35 |
M |
29 |
| 6/8 |
50 |
50 |
50 |
48 |
53 |
40 |
36 |
35 |
37 |
38 |
31 |
51 |
35 |
M |
38 |
| 6/9 |
58 |
60 |
58 |
71 |
65 |
51 |
50 |
54 |
64 |
58 |
51 |
57 |
54 |
M |
53 |
| 610 |
48 |
53 |
42 |
57 |
52 |
44 |
37 |
45 |
45 |
44 |
32 |
43 |
46 |
42 |
36 |
| 6/11 |
71 |
83 |
66 |
81 |
92 |
67 |
51 |
65 |
70 |
41 |
51 |
80 |
71 |
89 |
79 |
| 6/12 |
61 |
23 |
22 |
36 |
30 |
36 |
M |
35 |
37 |
38 |
27 |
27 |
41 |
M |
25 |
| 6/13 |
32 |
27 |
31 |
32 |
28 |
35 |
25 |
36 |
32 |
36 |
21 |
30 |
39 |
21 |
20 |
| 6/14 |
31 |
28 |
23 |
39 |
31 |
40 |
29 |
35 |
35 |
38 |
23 |
28 |
44 |
33 |
27 |
| 6/15 |
31 |
28 |
27 |
41 |
33 |
41 |
28 |
37 |
37 |
40 |
25 |
30 |
46 |
34 |
30 |
| 6/16 |
32 |
21 |
19 |
31 |
25 |
49 |
25 |
33 |
32 |
34 |
24 |
23 |
46 |
31 |
23 |
| 6/17 |
34 |
41 |
37 |
54 |
42 |
57 |
35 |
38 |
48 |
44 |
31 |
43 |
52 |
39 |
35 |
| 6/18 |
40 |
45 |
42 |
50 |
48 |
56 |
32 |
34 |
46 |
47 |
26 |
38 |
55 |
46 |
35 |
| 6/19 |
46 |
75 |
52 |
M |
67 |
67 |
46 |
60 |
61 |
52 |
39 |
48 |
63 |
64 |
52 |
| 6/20 |
71 |
74 |
70 |
M |
78 |
58 |
57 |
62 |
66 |
68 |
45 |
73 |
58 |
69 |
68 |
| 6/21 |
71 |
90 |
86 |
M |
97 |
55 |
88 |
89 |
89 |
94 |
69 |
92 |
59 |
95 |
81 |
| 6/22 |
64 |
60 |
41 |
M |
58 |
65 |
40 |
59 |
60 |
47 |
51 |
50 |
72 |
51 |
52 |
| 6/23 |
61 |
75 |
52 |
M |
73 |
64 |
67 |
79 |
82 |
62 |
77 |
87 |
71 |
71 |
70 |
| 6/24 |
44 |
59 |
40 |
M |
56 |
56 |
39 |
47 |
54 |
42 |
41 |
52 |
53 |
50 |
46 |
| 6/25 |
64 |
71 |
66 |
M |
71 |
57 |
57 |
62 |
55 |
59 |
43 |
61 |
57 |
67 |
51 |
| 6/26 |
72 |
74 |
67 |
M |
88 |
68 |
80 |
97 |
109 |
91 |
71 |
96 |
80 |
85 |
83 |
| 6/27 |
53 |
61 |
55 |
82 |
68 |
67 |
57 |
72 |
76 |
64 |
M |
66 |
75 |
63 |
61 |
| 6/28 |
45 |
43 |
37 |
58 |
49 |
61 |
37 |
M |
54 |
55 |
M |
41 |
63 |
41 |
M |
| 6/29 |
39 |
47 |
34 |
51 |
41 |
40 |
39 |
M |
42 |
40 |
M |
46 |
32 |
42 |
M |
| 6/30 |
51 |
72 |
60 |
68 |
74 |
45 |
51 |
M |
61 |
59 |
M |
64 |
38 |
M |
M |
July 2002 Peak 8-HR Ozone Concentration (PPB) at MA Monitors

| Date |
Adams |
Aga- wam |
Am- herst |
Blue Hill |
Chic- opee |
Fair- haven |
Law- rence |
L. Island |
Lynn |
New- bury |
Rox- bury |
Stow |
Truro |
Ware |
Wor- cester |
| 7/1 |
67 |
58 |
67 |
83 |
69 |
87 |
56 |
74 |
74 |
66 |
41 |
64 |
81 |
64 |
59 |
| 7/2 |
68 |
54 |
63 |
81 |
67 |
105 |
55 |
69 |
78 |
73 |
45 |
57 |
99 |
62 |
56 |
| 7/3 |
59 |
50 |
49 |
79 |
63 |
86 |
60 |
102 |
98 |
81 |
M |
49 |
93 |
56 |
M |
| 7/4 |
51 |
46 |
47 |
58 |
53 |
81 |
46 |
63 |
58 |
53 |
40 |
44 |
86 |
44 |
M |
| 7/5 |
34 |
41 |
32 |
42 |
41 |
41 |
32 |
36 |
43 |
38 |
30 |
39 |
41 |
38 |
32 |
|
7/6 |
39 |
40 |
36 |
44 |
44 |
47 |
30 |
33 |
42 |
37 |
30 |
34 |
45 |
38 |
31 |
| 7/7 |
44 |
36 |
34 |
33 |
41 |
30 |
23 |
23 |
34 |
35 |
22 |
30 |
32 |
38 |
29 |
| 7/8 |
60 |
56 |
55 |
88 |
58 |
77 |
45 |
74 |
83 |
56 |
71 |
69 |
78 |
56 |
57 |
| 7/9 |
72 |
73 |
55 |
103 |
83 |
72 |
59 |
86 |
100 |
80 |
69 |
81 |
74 |
77 |
74 |
| 7/10 |
31 |
35 |
32 |
42 |
36 |
45 |
24 |
36 |
32 |
38 |
28 |
31 |
40 |
36 |
29 |
| 7/11 |
31 |
33 |
30 |
38 |
34 |
21 |
22 |
34 |
38 |
34 |
26 |
30 |
35 |
33 |
27 |
| 7/12 |
43 |
45 |
46 |
62 |
51 |
53 |
44 |
53 |
54 |
55 |
41 |
46 |
54 |
59 |
43 |
| 7/13 |
75 |
81 |
66 |
79 |
83 |
57 |
59 |
81 |
71 |
66 |
78 |
61 |
61 |
79 |
71 |
| 7/14 |
70 |
75 |
73 |
89 |
80 |
47 |
79 |
79 |
86 |
88 |
74 |
82 |
42 |
77 |
71 |
| 7/15 |
51 |
50 |
53 |
81 |
59 |
66 |
55 |
64 |
75 |
74 |
53 |
62 |
54 |
57 |
69 |
| 7/16 |
31 |
37 |
33 |
M |
36 |
45 |
24 |
40 |
38 |
37 |
32 |
31 |
42 |
34 |
38 |
| 7/17 |
80 |
69 |
55 |
65 |
66 |
51 |
42 |
49 |
47 |
45 |
45 |
65 |
55 |
70 |
76 |
| 7/18 |
78 |
80 |
68 |
83 |
84 |
104 |
57 |
67 |
78 |
64 |
M |
63 |
105 |
70 |
74 |
| 7/19 |
45 |
61 |
34 |
53 |
68 |
80 |
M |
36 |
42 |
M |
27 |
32 |
74 |
54 |
43 |
| 7/20 |
36 |
44 |
33 |
32 |
37 |
30 |
M |
29 |
31 |
M |
22 |
34 |
49 |
34 |
40 |
| 7/21 |
51 |
58 |
57 |
52 |
64 |
38 |
38 |
49 |
50 |
M |
46 |
49 |
33 |
64 |
58 |
| 7/22 |
74 |
97 |
91 |
66 |
108 |
41 |
78 |
64 |
76 |
81 |
56 |
76 |
45 |
M |
89 |
| 7/23 |
64 |
61 |
55 |
84 |
68 |
56 |
71 |
80 |
83 |
79 |
56 |
75 |
58 |
66 |
94 |
| 7/24 |
19 |
42 |
32 |
28 |
40 |
24 |
20 |
26 |
25 |
27 |
12 |
28 |
27 |
37 |
35 |
| 7/25 |
37 |
48 |
40 |
34 |
52 |
30 |
30 |
M |
32 |
33 |
27 |
40 |
32 |
47 |
48 |
| 7/26 |
42 |
44 |
40 |
33 |
49 |
30 |
28 |
31 |
31 |
31 |
23 |
29 |
32 |
42 |
42 |
| 7/27 |
47 |
23 |
28 |
31 |
29 |
32 |
28 |
28 |
29 |
32 |
22 |
28 |
33 |
30 |
31 |
| 7/28 |
50 |
19 |
28 |
49 |
32 |
49 |
41 |
40 |
40 |
44 |
38 |
33 |
40 |
34 |
45 |
| 7/29 |
59 |
52 |
49 |
60 |
60 |
64 |
45 |
49 |
57 |
51 |
33 |
48 |
74 |
55 |
55 |
| 7/30 |
50 |
55 |
48 |
64 |
58 |
73 |
47 |
51 |
59 |
51 |
37 |
50 |
88 |
50 |
54 |
| 7/31 |
47 |
47 |
40 |
57 |
47 |
75 |
45 |
60 |
52 |
M |
33 |
40 |
60 |
40 |
40 |
August 2002 Peak 8-HR Ozone Concentration (PPB) at MA Monitors

| Date |
Adams |
Aga- wam |
Am- herst |
Blue Hill |
Chic- opee |
Fair- haven |
Law- rence |
L. Island |
Lynn |
New- bury |
Rox- bury |
Stow |
Truro |
Ware |
Wor- cester |
| 8/1 |
53 |
65 |
48 |
74 |
61 |
62 |
55 |
56 |
53 |
46 |
33 |
69 |
50 |
59 |
50 |
| 8/2 |
56 |
61 |
48 |
71 |
66 |
43 |
51 |
45 |
42 |
39 |
36 |
61 |
28 |
52 |
56 |
| 8/3 |
50 |
56 |
45 |
86 |
61 |
76 |
53 |
61 |
68 |
61 |
61 |
53 |
70 |
48 |
52 |
| 8/4 |
74 |
84 |
65 |
84 |
92 |
83 |
58 |
77 |
88 |
78 |
60 |
69 |
80 |
77 |
76 |
| 8/5 |
59 |
46 |
49 |
76 |
58 |
80 |
58 |
69 |
72 |
66 |
50 |
62 |
84 |
57 |
68 |
|
8/6 |
22 |
28 |
23 |
31 |
29 |
33 |
27 |
29 |
35 |
29 |
26 |
26 |
43 |
28 |
28 |
| 8/7 |
28 |
30 |
29 |
41 |
33 |
44 |
32 |
35 |
39 |
32 |
30 |
31 |
42 |
31 |
33 |
| 8/8 |
30 |
30 |
28 |
| |