Jump to main content.

MASSACHUSETTS

The tables below contain the number of exceedances of the eight-hour ozone standard, the four highest eight-hour average concentrations and the dates they occured for each ozone monitor in Massachusetts. For 1999 and after, click on the date for the corresponding eight-hour average peak ozone map for that day.

ADAMS | AGAWAM | AMHERST |BLUE HILL | BOSTON - LONG ISLAND | CHELMSFORD | CHELSEA | CHICOPEE | EASTON | NORTH EASTON | FAIRHAVEN | HAVERHILL | LAWRENCE | LYNN | MARTHA'S VINEYARD | NEWBURY | SCITUATE | STOW | SUDBURY | TRURO | WALTHAM | WARE | WORCESTER

ADAMS

Operating from 1995 to Present
Year Total # Days > 0.084 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
1994 0 0.079 May 31 0.078 Aug 4 0.074 May 30 0.074 Aug 9
1995 0 0.083 June 18 0.077 Aug 1 0.073 June 19 0.072 June 29
1996 2 0.096 June 7 0.085 Aug 7 0.084 June 2 0.081 June 1
1997* 1 0.090 June 30 0.084 July 13 0.082 July 14 0.078 June 12
1998* 0 0.076 May 29 0.074 July 14 0.073 Sept 15 0.069 Sept 14
1999 1 0.086 May 31 0.083 June 1 0.080 July 16 0.075 June 24
2000* 1 0.090 June 10 0.078 June 11 0.075 May 6 0.072 June 9
2001 16 0.108 June 19 0.099 June 20 0.093 May 4 0.092 June 14
2002 4 0.101 Aug 14 0.096 Aug 13 0.091 Aug 12 0.086 Aug 11
2003 2 0.104 June 26 0.100 June 25 0.083 June 27 0.083 July 2
2004 1 0.086 July 22 0.081 June 24 0.075 Aug 10 0.071 July 1
2005 6 0.091 June 9 0.089 Sept 13 0.087 June 24 0.087 June 25
2006 0 0.082 June 18 0.079 June 19 0.077 Aug 14 0.076 June 17
2007 2 0.093 June 8 0.086 May 25 0.082 May 24 0.080 Sept 7

*Site did not meet 75% minimum data completeness requirement

TOP

AGAWAM

Operating from 1982 to 2002
Year Total # Days > 0.084 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
1994 8 0.103 July 20 0.100 Aug 4 0.090 Aug 25 0.089 Aug 1
1995 6 0.109 July 13 0.096 June 30 0.096 Sept 7 0.093 July 4
1996 2 0.087 Aug 8 0.085 July 8 0.084 Aug 7 0.082 July 12
1997 9 0.097 July 1 0.094 Aug 11 0.093 June 21 0.092 July 25
1998 1 0.093 Aug 24 0.082 July 14 0.081 July 16 0.080 July 15
1999 1 0.088 June 1 0.084 May 31 0.083 July 30 0.081 Aug 17
2000 1 0.089 June 10 0.080 June 16 0.073 June 26 0.071 June 2
2001 2 0.091 June 19 0.086 July 23 0.082 July 22 0.081 June 20
2002 6 0.118 Aug 14 0.112 Aug 13 0.101 Aug 12 0.097 July 22

TOP

AMHERST

Operating from 1988 to Present
Year Total # Days > 0.084 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
1994 7 0.097 July 9 0.097 Aug 4 0.096 June 17 0.091 July 20
1995 3 0.089 Aug 31 0.085 Sept 7 0.085 June 30 0.084 July 28
1996 3 0.087 July 12 0.086 Aug 8 0.085 July 8 0.081 Aug 7
1997 2 0.098 July 1 0.092 Aug 11 0.083 July 27 0.082 Aug 10
1998 2 0.100 July 14 0.096 July 16 0.083 July 27 0.081 July 28
1999 3 0.098 July 31 0.089 June 1 0.085 June 27 0.084 May 31
2000 1 0.086 June 10 0.082 June 16 0.066 June 25 0.065 June 1
2001 3 0.102 June 19 0.086 June 20 0.085 June 13 0.084 May 4
2002 4 0.107 Aug 14 0.096 Aug 13 0.091 July 22 0.086 June 21
2003 0 0.069 June 29 0.066 April 16 0.061 June 27 0.061 July 24
2004 1 0.088 July 22 0.079 Aug 10 0.076 June 24 0.062 June 8
2005 1 0.092 June 9 0.079 June 25 0.078 April 20 0.078 June 8
2006 1 0.102 June 19 0.078 July 27 0.075 July 10 0.074 Aug 14
2007 3 0.094 July 10 0.091 July 9 0.087 Aug 30 0.080 June 19

TOP

BLUE HILL

Operating from 2002 to Present
Year Total # Days > 0.084 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
2002 17 0.134 Aug 13 0.116 Aug 12 0.112 Aug 14 0.107 Sept 9
2003 5 0.109 June 27 0.091 June 26 0.090 June 25 0.089 Aug 22
2004 2 0.100 June 8 0.095 June 17 0.084 July 30 0.078 June 9
2005 4 0.103 June 25 0.091 June 24 0.090 April 20 0.089 June 26
2006 2 0.087 July 18 0.086 June 18 0.084 June 19 0.083 July 2
2007 7 0.095 July 26 0.095 Aug 3 0.094 May 25 0.088 Aug 30

TOP

BOSTON - LONG ISLAND

Operating from 1999 to Present
Year Total # Days > 0.084 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
1999 4 0.102 July 16 0.100 June 24 0.089 June 1 0.087 May 31
2000 0 0.084 June 10 0.073 June 1 0.072 Aug 9 0.070 June 2
2001 9 0.111 June 20 0.107 June 19 0.100 Aug 2 0.094 July 24
2002 10 0.126 Aug 13 0.117 Aug 14 0.102 July 3 0.102 Sept 9
2003 1 0.102 June 27 0.083 June 25 0.078 June 26 0.078 July 4
2004 1 0.094 June 8 0.081 July 22 0.080 July 23 0.079 July 30
2005 5 0.095 June 25 0.091 June 26 0.089 Aug 11 0.086 June 24
2006 0 0.083 June 22 0.083 July 2 0.083 July 18 0.079 July 1
2007 0 0.082 Sept 25 0.080 April 23 0.076 Sept 26 0.073 Aug 3

TOP

CHELMSFORD

Operating from 2005 to Present
Year Total # Days > 0.084 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
2005 2 0.095 June 27 0.085 June 25 0.080 April 20 0.079 June 24
2006 0 0.083 June 19 0.077 June 22 0.073 Mar 31 0.071 June 18
2007 5 0.095 Aug 30 0.091 Aug 3 0.089 May 25 0.087 June 27

TOP

CHELSEA

Operating from 1984 to 1999
Year Total # Days > 0.084 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
1994 3 0.089 June 18 0.086 June 17 0.086 Aug 9 0.074 July 19
1995 1 0.101 Aug 1 0.084 July 13 0.083 June 30 0.083 Aug 10
1996 0 0.075 July 12 0.073 Aug 9 0.072 Aug 7 0.071 Aug 6
1997 2 0.086 June 30 0.085 Aug 10 0.081 June 21 0.075 June 12
1998 4 0.095 Aug 24 0.088 May 29 0.088 July 14 0.087 July 15
1999 3 0.102 July 16 0.093 July 17 0.089 June 24 0.084 May 31

TOP

CHICOPEE

Operating from 1983 to Present
Year Total # Days > 0.084 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
1994 8 0.102 Aug 4 0.102 July 20 0.097 June 17 0.095 Aug 1
1995 8 0.101 July 13 0.100 June 30 0.095 July 4 0.093 July 28
1996 3 0.094 July 8 0.094 Aug 7 0.087 Aug 8 0.082 July 12
1997 7 0.104 July 1 0.097 Aug 11 0.095 June 21 0.092 July 27
1998 5 0.104 July 16 0.102 July 14 0.097 July 15 0.093 Aug 24
1999 7 0.095 June 1 0.093 July 30 0.089 July 16 0.088 June 27
2000 1 0.090 June 10 0.084 June 16 0.084 June 26 0.079 June 2
2001 9 0.105 June 19 0.098 June 20 0.097 May 4 0.090 May 2
2002 10 0.118 Aug 14 0.115 Aug 12 0.108 July 22 0.108 Aug 13
2003 3 0.099 June 25 0.093 June 29 0.089 June 27 0.084 June 26
2004 1 0.093 July 22 0.083 Aug 10 0.080 June 24 0.078 May 15
2005 8 0.104 June 9 0.098 Aug 12 0.095 June 26 0.090 June 25
2006 5 0.119 June 19 0.102 June 18 0.091 June 22 0.090 July 27
2007 8 0.112 July 9 0.109 July 10 0.102 Aug 3 0.098 Aug 30

TOP

EASTON

Operating from 1996 to 2001
Year Total # Days > 0.084 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
1996 3 0.094 July 6 0.087 Aug 7 0.085 Aug 23 0.084 June 17
1997 7 0.096 June 30 0.095 June 12 0.094 July 17 0.093 June 21
1998 7 0.105 Aug 24 0.091 July 15 0.090 Sept 6 0.088 Sept 27
1999 3 0.091 June 24 0.089 July 16 0.086 July 17 0.083 July 15
2000 0 0.081 May 7 0.077 July 3 0.074 June 9 0.072 June 10
2001 14 0.107 Aug 2 0.103 Aug 9 0.101 June 20 0.098 June 19

TOP

NORTH EASTON

Operating from 1982 to 1996
Year Total # Days > 0.084 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
1994 8 0.103 Aug 9 0.102 June 18 0.098 July 13 0.098 July 20
1995 10 0.108 Aug 1 0.108 Aug 2 0.106 Aug 10 0.104 July 14
1996 1 0.085 July 6 0.078 June 17 0.076 Aug 7 0.075 Aug 23

TOP

FAIRHAVEN

Operating from 1982 to Present
Year Total # Days > 0.084 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
1994 1 0.098 July 13 0.080 Aug 4 0.080 Aug 28 0.077 July 12
1995 9 0.125 June 19 0.124 Aug 21 0.107 June 18 0.107 July 14
1996 6 0.113 July 18 0.104 June 14 0.092 May 20 0.092 July 6
1997 12 0.107 July 14 0.106 July 17 0.103 Aug 2 0.092 Aug 3
1998 2 0.099 Sept 6 0.087 May 28 0.084 Aug 4 0.083 Aug 3
1999 8 0.112 July 16 0.109 June 7 0.101 June 23 0.098 July 6
2000 3 0.105 June 10 0.090 July 2 0.085 Aug 8 0.082 May 7
2001 8 0.117 Aug 7 0.113 Aug 9 0.109 May 4 0.101 Aug 2
2002 5 0.105 July 2 0.102 July 18 0.087 July 1 0.087 July 3
2003 8 0.117 June 27 0.101 Aug 16 0.100 June 26 0.098 June 25
2004 1 0.099 June 9 0.084 June 8 0.082 May 11 0.080 July 4
2005 1 0.086 Aug 11 0.084 April 20 0.084 Aug 2 0.082 June 8
2006 4 0.107 July 18 0.104 Aug 1 0.093 Aug 2 0.085 July 17
2007 1 0.086 May 25 0.083 July 8 0.082 Aug 2 0.075 June 28

TOP

HAVERHILL

Operating from 2004 to Present
Year Total # Days > 0.084 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
2004 1 0.091 July 22 0.078 July 23 0.078 July 30 0.072 Aug 10
2005 0 0.084 Sept 14 0.079 June 25 0.079 July 26 0.078 June 24
2006 1 0.089 June 19 0.081 June 22 0.075 July 25 0.075 July 26
2007 6 0.096 Aug 3 0.095 Aug 30 0.092 May 25 0.090 June 27

TOP

LAWRENCE

Operating from 1982 to 2002
Year Total # Days > 0.084 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
1994 2 0.096 June 18 0.087 July 21 0.084 Aug 9 0.082 July 20
1995 0 0.077 July 13 0.074 Aug 9 0.071 June 30 0.069 July 5
1996 1 0.085 Aug 8 0.081 July 12 0.080 Aug 4 0.079 June 2
1997 2 0.108 July 1 0.088 Aug 11 0.081 Aug 10 0.078 July 27
1998 1 0.088 Aug 24 0.081 July 16 0.077 July 14 0.076 May 29
1999 1 0.088 June 1 0.083 May 31 0.075 June 2 0.068 June 6
2000 0 0.067 June 16 0.062 June 10 0.062 May 4 0.060 Aug 9
2001 0 0.073 June 19 0.066 June 20 0.063 June 14 0.062 July 24
2002 6 0.109 Aug 12 0.105 Aug 13 0.102 Aug 14 0.088 June 21

TOP

LYNN

Operating from 1993 to Present
Year Total # Days > 0.084 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
1994 6 0.097 June 17 0.096 June 18 0.094 July 21 0.090 Aug 9
1995 7 0.116 Aug 1 0.100 July 13 0.098 Aug 10 0.094 June 30
1996 2 0.091 Aug 9 0.085 Aug 23 0.083 July 8 0.083 Aug 7
1997 6 0.104 July 1 0.096 June 30 0.093 June 21 0.091 Aug 10
1998 7 0.108 Aug 24 0.105 July 15 0.103 May 29 0.100 July 14
1999 6 0.109 July 16 0.101 June 24 0.096 July 17 0.088 May 31
2000 1 0.089 June 10 0.073 June 1 0.073 July 3 0.070 Aug 9
2001 11 0.111 June 20 0.102 Aug 2 0.101 July 24 0.100 July 23
2002 13 0.123 Aug 13 0.122 Aug 14 0.109 June 26 0.100 July 9
2003 3 0.100 June 27 0.092 Aug 22 0.088 June 25 0.079 June 26
2004 2 0.092 June 8 0.088 July 30 0.083 July 23 0.083 Aug 3
2005 6 0.099 June 25 0.096 June 26 0.094 June 24 0.088 July 26
2006 1 0.086 June 19 0.084 June 18 0.079 June 22 0.078 July 18
2007 4 0.103 Aug 3 0.102 July 26 0.093 May 25 0.088 June 27

TOP

MARTHA'S VINEYARD

Operating from 2004 to Present
Year Total # Days > 0.084 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
2004 0 0.078 July 4 0.074 June 23 0.074 July 22 0.072 June 30
2005 4 0.106 Aug 11 0.104 Aug 2 0.088 Sept 12 0.087 June 5
2006 4 0.112 Aug 1 0.112 Aug 2 0.101 Aug 3 0.089 July 29
2007 3 0.094 May 26 0.091 May 25 0.088 June 17 0.077 April 23

TOP

NEWBURY

Operating from 1994 to Present
Year Total # Days > 0.084 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
1994 0 0.084 Aug 26 0.084 Aug 28 0.082 Aug 25 0.077 Sept 17
1995 3 0.101 Aug 10 0.098 June 30 0.092 Aug 1 0.083 July 5
1996 2 0.087 Aug 6 0.085 July 8 0.084 Aug 8 0.083 July 12
1997 6 0.106 June 30 0.104 July 1 0.087 June 21 0.087 July 27
1998 6 0.103 May 29 0.096 July 16 0.096 Aug 5 0.089 July 14
1999 6 0.112</