The product distributions have been calculated for the more abundant alkanes contributing most of the carbon atoms in the alkane fraction of an ambient air hydrocarbon mixture reasonably representative of U.S. emissions. The effects of ambient temperatures on product yields has been calculated for a range of temperatures from 250K to 330K. Chemical lifetimes are estimated at 300K under summertime conditions for hydrocarbons and for products of alkane photooxidation in the atmosphere. The calculations predict a substantial effect of temperature on product yields. A large decrease in alkyl nitrate yields and a smaller decrease in ketone yields occurs with increasing temperature. The yields of the short-lived more reactive aldehydes undergo substantial increases with increasing temperature. Four lower molecular weight oxygenated products account for over half of the total alkane carbon atoms converted to products. The effects of increased temperature on product reactivity and radical production may also influence O3 production.