Year,Jan.,Feb.,Mar.,Apr.,May.,Jun.,Jul.,Aug.,Sep.,Oct.,Nov.,Dec.,24-Hour Annual Avg., 1990,10621,11353,13345,13959,13834,15507,16417,16915,15390,13435,13013,10571,13708, 1991,10755,12485,13901,14210,14517,15994,17066,18317,16485,14339,13046,12397,14470, 1992,11925,13210,14299,15208,15063,16547,17784,17925,17192,15419,13966,12195,15105, 1993,10792,12493,14908,15859,15777,17363,19136,19422,18075,16073,14485,13555,15679, 1994,13354,13737,16116,16548,16032,17547,18947,19308,18619,15825,14529,13743,16206, 1995,13370,14776,15760,16623,16801,18426,19652,19899,18900,17163,16445,15466,16940, 1996,13622,15333,16170,16163,,19403,20605,21059,19573,17502,16558,14612,, 1997,14226,15919,17485,18054,18106,18889,21305,22080,20256,18407,17596,16140,18205, 1998,15078,16453,18022,19383,19275,21081,22642,23246,21416,19453,18536,16502,19257, 1999,15954,17031,19271,20063,20007,21853,23146,24216,22368,20207,19024,17584,20060, 2000,16570,18131,19723,20384,20611,22937,24426,24479,21958,20222,18136,17251,20402, 2001,16116,17672,19268,19845,20442,22323,23610,24231,22614,20524,19431,16921,20250, 2002,16486,18528,20300,20828,20925,,24267,24608,22651,20927,19775,19132,, 2003,17950,18804,20067,21274,21910,23466,24804,25408,22890,21331,19884,18324,21343, 2004,16890,17399,21184,22067,21340,23080,24865,24432,23289,20298,19724,18575,21095, 2005,15854,18655,20708,21162,21038,23111,24626,24470,21880,19990,19146,17799,20703, 2006,16842,18582,20241,21271,21181,23497,24371,24432,23503,21154,20241,19050,21197, 2007,17663,19313,21441,21894,21908,23920,25198,25257,23798,22014,21349,18293,21837, 2008,17302,17902,20422,21277,21248,21964,23584,23316,22479,20812,19959,17326,20633, 2009,17613,19231,20384,22343,22148,24174,26266,25174,24534,21892,20638,18940,21945, 2010,17944,19933,21557,23029,22464,24549,26765,,24574,22157,19243,18741,, 2011,18327,19384,20764,22555,22077,23727,25628,25774,24023,22164,20506,19415,22029, 2012,18132,19390,20873,22165,22098,23488,25603,25334,24146,22096,20466,19056,21904, 2013,17059,18977,21254,22412,22688,24078,25839,25561,23589,21914,20376,19082,21902, 2014,18271,19192,21468,23155,23501,25709,27629,27007,25377,24047,21580,21174,23176, 2015,20083,22477,24313,25370,25412,28035,29599,28379,27420,25292,23043,21433,25071, 2016,20290,22830,25290,26362,26752,29565,31268,29480,29018,26554,24924,21164,26125, 2017,19575,22101,25745,27054,27050,28662,31024,32242,28503,26245,24965,23108,26356, 2018,22040,23369,25496,27247,27872,30633,32198,31583,30408,27596,26077,22935,27288, 2019,22145,22443,26548,27686,27967, , , ,29757,27803,25663,24452,26052, 2020,22371,24543,22855,16749,23122,28603,31270,30433,29812,27197,23549,22650,25263, 2021,22910,23101,26939,28720,30079,34099,35593,33102,32813,29712,27448,24126,29053, 2022,22728,25264,26772,28602,29640,31468,32178,31787,36287,29889,26355,23694,28722, 2023,23100,24522,26247,28487,30633,33313,34691,34129,32467,30971, , ,29856, 2024, , , , , , , , , , , , , ,