KORD 070907Z 03005KT 10SM -RA BKN008 BKN044 OVC095 08/07 A2961
KORD 070851Z 00000KT 6SM -RA BR FEW008 SCT045 OVC095 08/07 A2963
KORD 070751Z 01011KT 10SM BKN007 BKN044 OVC100 08/07 A2959
KORD 070651Z 05007KT 10SM -RA BKN005 OVC050 09/08 A2958
KORD 070551Z 03009KT 8SM BKN005 OVC050 09/08 A2959
KORD 070518Z 36009G16KT 9SM SCT005 OVC060 09/07 A2958
KORD 070451Z 03008KT 10SM BKN065 BKN080 08/07 A2955
KORD 070351Z 01009KT 10SM SCT075 09/07 A2951
KORD 070251Z 06005KT 10SM SCT075 09/07 A2951
KORD 070151Z 03007KT 10SM OVC070 11/08 A2951
KORD 070058Z 05010KT 10SM BKN065 OVC080 13/09 A2950
KORD 070051Z 07010G21KT 10SM BKN060 OVC075 14/09 A2949
KORD 062351Z 16003KT 10SM OVC065 22/15 A2947
KORD 062251Z 22010KT 10SM SCT060 24/14 A2949
KORD 062151Z 23019G26KT 10SM BKN055 24/15 A2950
KORD 062051Z 23017G23KT 10SM FEW045 OVC055 24/16 A2950
KORD 061951Z 13004KT 8SM OVC040 20/14 A2952
http://www.navlost.eu/aero/metar
If you want each full atis you will probably have to contact the ORD aviation authority, They should have an archive somewhere.