* WCS quoted at $27/bbl under WTI
* Light synthetic quoted at $6.25/bbl under WTI
* Two Midwest refineries add to demand after upkeep
CALGARY, Alberta, Nov 9 (Reuters) - Canadian cash crude oil prices moved higher on Friday, with more refinery capacity coming back on line in the U.S. Midwest following maintenance.
Western Canada Select heavy blend for December delivery was last quoted at $27 a barrel under benchmark West Texas Intermediate, compared with $28.90 a barrel under on Tuesday, according to Shorcan Energy Brokers.
December light synthetic, derived from the Alberta oil sands, fetched $6.25 a barrel under WTI, up 65 cents a barrel.
Heavy crude prices have edged up this week, but remain well below levels of a month ago due to much tighter available pipeline capacity on Enbridge Inc's export network and TransCanada Corp's Keystone line to the U.S. Midwest and Oklahoma from Alberta.
In addition, BP Plc began major maintenance at its 337,000 barrel a day Whiting, Indiana, refinery.
However, adding to demand this week, Marathon Petroleum Corp's 106,000 bpd refinery in Detroit restarted operations after completing tie-ins for its $2.2 billion heavy oil upgrade project.
Another major buyer of Canadian crude, the 306,000 barrel a day Wood River, Illinois, refinery, owned by Phillips 66 and Cenovus Energy Inc, is also expected to ramp up production soon following a turnaround that started in October.