Ozone Data

For current year data, visit our 2025 ScoreCard

Ozone Alert Days by Year and Month

Year May June July Aug Sept Oct Total
2025 0
2024 18 14 12, 19 6 4 6
2023 27 6, 7, 8, 9, 14, 16, 17 10, 17, 21,22, 23, 26 14
2022 22, 29 11, 14, 19, 20, 21 7
2021 15, 16, 17 3
2020 0
2019 20 5 2
2018 9, 10, 17 None 19, 20, 25 1, 2, 10 None 9
2017 None 8 None 3 13 3
2016 20, 28 28 10 4
2015 None 10 None None None 1
2014 None None 24 None None None 1
2013 None 13 12 22 4 None 4
2012 18 25, 26, 27, 28, 29 10, 11, 12, 13, 21, 22, 28 2, 3, 6, 7, 8, 10 4, 5 None 21
2011 None 3, 15, 24, 28 2, 6, 8, 9, 15, 29 3, 4, 5, 17, 20, 21, 24, 25, 26, 27, 28 1, 2, 3, 13 None 25
2010 28 None None 12, 19, 23, 28 None None 5
2009 None 24, 25, 26, 27, 30 1, 7, 11, 16 13, 25 None None 11
2008 None None 18, 28, 31 1, 2, 4, 5, 26 None None 8
2007 None None None 2, 3, 14, 25, 16 None None 5
2006 25 12, 15, 29, 30 1, 2, 17, 19, 20, 21 24 None None 12
2005 None 21, 22, 24, 25, 26 30 1, 2, 4, 10 3, 4, 5 None 13
2004 None None 15, 21, 22 None None None 3
2003 None None 2, 3, 30 6, 7, 23, 26, 27 None None 8
2002 None 24, 25 9, 10, 25 6, 9, 31 None None 8
2001 None 26 11, 25 3, 4, 6, 7 14 None 8
2000 None None 17 1, 2, 3, 4, 15, 16, 23, 24, 25, 26 2, 3, 4, 8 None 15
1999 None None 26 3, 9, 10, 11, 12, 17, 18, 19, 25, 26, 27, 29, 30, 31 1, 2 None 17
1998 None None 15, 17 21, 22 1, 2, 4, 5, 6, 7 None 10
1997 None None None None None None None
1996 None 13, 14, 18, 20 3, 14 14 None None 7
1995 None 21, 22 6 25, 28, 29, 30, 31 1, Oct 11 None 10
1994 None 20, 21, 22, 29 None None None None 4
1993 None None 21, 28, 29, 30 14, 17, 18, 20, 21, 28 None None 10
1992 None 19, 25 1, 28 None None None 4
1991 None None 30 14,15,26 None None 4

Number of Ozone Exceedance Days by Year and Month

YEAR
MARCH
APRIL
MAY
JUNE
JULY
AUGUST
SEPT
OCT
TOTAL # DAYS .070ppm standard
2022
 3 22, 28, 30 8, 11, 14, 18, 19, 20, 21 20 15 12  
2021
 14, 15, 17 4 4  
2020
 24th 1  
2019
 8 6 2  
2018
 24 7, 8, 9, 26   19, 20, 25 2, 9, 11     11  
2017
          
14
  
1
 
Previous .075 ppm standard
2016
7
5
2
2
2015
7
15
2
2014
 
0
2013
13
10, 13
4, 6, 7
  
6
2012
15, 16
24, 25, 26, 28
8, 9, 11, 12, 14, 20, 21, 27
1, 2, 3, 4, 6, 7, 8, 9, 12, 21, 29
6
  
26
2011
12, 13, 17
23
5, 6, 7, 14, 15, 25
3, 4, 6, 9, 15, 19, 20, 21, 26, 27, 28, 30
1, 13, 28
  
25
2010
26
27
 
2
2009
22
24, 26
2, 15
12
 
6
2008
3, 23, 28, 31
4, 5
28
  
7
 
.075 ppm standard
Previous .084 ppm standard
2007
13, 14
 
4
2
2006
8, 30
18, 20
4, 19, 23
15, 30
  
27
9
2005
21, 22
29
8
1, 2
  
23
6
2004
 
3
0
2003
12
30
19
21, 29
22, 23, 24, 25,
 
22
9
2002
23, 24
6, 8, 9
10
  
24
6
2001
26, 27
4, 5, 7
13
  
26
6
2000
14, 19
2, 15, 23
1, 2, 3, 13, 19
  
24
10