A process and system are described for producing a synthetic crude oil by contacting a synthesis gas with a combination of a synthesis gas conversion catalyst and a hydroconversion catalyst in a synthesis gas reactor. The synthesis gas can be obtained from gas associated with crude oil production, i.e., associated gas, in a synthesis gas generator. The synthetic crude oil can be blended with a natural crude oil to produce a blended stabilized crude oil having 2 wt % or more of the synthetic crude oil. The resulting blended stabilized crude oil has improved flow characteristics including a pour point of 30° C. or less.