YEAR Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual 24-hr Avg. 1990 30899 32618 33025 32939 32932 33636 31995 33310 31034 32133 21650 13727 29972 1991 13432 14353 14122 14542 14531 14319 13603 14147 13157 13683 9219 26087 14621 1992 29162 32202 33978 32704 31117 33286 31592 22190 19734 20463 18931 15688 26804 1993 17325 19741 20925 20670 19756 19558 14741 15434 20667 20646 19772 20222 19105 1994 19318 20197 21338 20996 20375 21598 18799 19998 19389 19171 18482 18632 19852 1995 18699 19351 19601 19851 21153 19279 19827 19368 19597 19049 18978 1996 18507 20063 20828 20582 20312 21292 19287 20050 19764 19417 18901 18482 19790 1997 18350 19437 19896 20281 20248 21131 19397 19826 19710 19511 18812 18915 19626 1998 18039 19924 20175 20474 20087 21031 19711 19999 19258 19108 18015 18801 19552 1999 18571 19107 19745 20135 19987 20462 18484 18563 17993 18133 17373 17438 18833 2000 17359 17879 18160 18279 18031 18848 18080 17853 17724 17779 16864 17284 17845 2001 16601 17541 17855 17992 17902 18845 17244 17751 16956 17128 16699 16403 17410 2002 16559 16691 16089 17376 17298 17301 16621 16947 16529 16925 16245 16155 16728 2003 14489 13907 13476 13937 13569 13990 13153 13029 14224 15050 14006 14787 13968 2004 14292 15222 15813 15598 15188 15663 15109 15611 15443 15166 14888 15267 15272 2005 14806 15781 16102 16110 15640 16334 15264 16169 15628 15343 15085 15101 15614 2006 15084 15976 16215 15883 16026 16300 14880 16090 15600 15609 15244 15073 15665 2007 15270 15846 16169 15929 15860 15692 15015 16072 15720 15700 14904 14689 15572 2008 14914 15604 15247 15740 15413 14952 14506